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Diseases » Respiratory syncytial virus » Diagnosis

Diagnosis of Respiratory syncytial virus

Respiratory syncytial virus Diagnosis: Book Excerpts

Tests and diagnosis discussion for Respiratory syncytial virus:

Diagnosis of RSV infection can be made by virus isolation, detection of viral antigens, detection of viral RNA, demonstration of a rise in serum antibodies, or a combination of these approaches. Most clinical laboratories use antigen detection assays to diagnose infection. (Source: excerpt from Respiratory Syncytial Virus: DVRD)

Diagnostic Tests for Respiratory syncytial virus: Online Medical Books

16 MEDICAL BOOKS ONLINE! Review excerpts from medical books online, free, without registration, for more information about diagnostis of Respiratory syncytial virus.

COUGH: Ask the following questions:
(Algorithmic Diagnosis of Symptoms and Signs)

Is it acute or chronic? Acute onset of a cough would suggest an acute URI, viral pneumonia, or bronchopneumonia. A chronic cough is more suggestive of pneumoconiosis, chronic bronchitis, emphysema, bronchiectasis, tuberculosis, carcinoma of the lung, or bronchial asthma.
Is there exposure to toxic fumes? The most common toxic fume is cigarette smoke. However, if one asks the patient's occupation one might find that he is a miner and therefore pneumoconiosis comes to mind. One might find that he is an aircraft maker or shipbuilder, in which case berylliosis and asbestosis would come to mind, or that he is a farmer and, therefore, farmer's lung would come to mind.
Is there significant sputum production? If so, what is the nature of the sputum? Purulent sputum would suggest a pneumonia, abscess, tuberculosis, or bronchiectasis; bloody sputum would suggest carcinoma of the lung, tuberculosis, and bronchiectasis; mucoid sputum would suggest asthma. If the sputum is foamy, one would consider congestive heart failure, mitral stenosis, and inhalation of poison gas.
Is there fever? If there is fever associated with the cough, obviously one would suspect an infectious process to be present. This could be viral or bacterial. Most likely the patient has bronchopneumonia, but the possibility of an abscess or pulmonary infarct would still have to be entertained.
What other symptoms and signs are associated with the cough? The first thing to be considered would be dyspnea. In acute cases dyspnea would be a sign of congestive heart failure, pulmonary embolism and, of course, advancing pneumonia. In chronic cases dyspnea would be a sign of emphysema, chronic pulmonary fibrosis, and chronic congestive heart failure. Wheezing would be a sign of asthma or congestive heart failure, but of course it is also found in pulmonary emphysema. Cardiomegaly would suggest congestive heart failure and if there is an associated murmur, that makes congestive heart failure even more likely. If there is hepatosplenomegaly, one would suspect a systemic disease involving the lungs such as periarteritis nodosa or other collagen diseases.
Is the patient taking drugs? Angiotensin-converting enzyme (ACE) inhibitors such as captopril are well known to cause cough.

DIAGNOSTIC WORKUP

If there is nasal stuffiness and a postnasal drip, a trial of antihistamines or decongestants is indicated before starting an expensive workup. All patients require a CBC and differential count, a sedimentation rate, and a chemistry panel. A sputum for routine smear and culture should be done, and in chronic cases a sputum for AFB culture and smear must be done. One should keep a high index of suspicion for Mycoplasma pneumoniae and Legionnaire's disease. Also, sputum for fungi culture should be done on chronic cases.

Asthma can be further elucidated and confirmed by doing a sputum for eosinophils. Carcinoma of the lung can be confirmed with a sputum for Pap smear. If there is fever, blood cultures may be useful and febrile agglutinins should also be done. An x-ray of the chest with anteroposterior, lateral, and apical lordotic views should be done, and when a tumor is suspected, tomography should be done or a CT scan. In cases of chronic cough, skin testing for coccidioidomycosis, cystoplasmosis, tuberculosis, and blastomycosis should be done. A Kveim test to rule out sarcoidosis may be necessary. When these tests fail to make a diagnosis, bronchoscopy and possibly bronchograms to look for a bronchiectasis should be done. Lung biopsy may be necessary also. Pulmonary function tests should be done in suspected cases of emphysema and asthma. Allergy skin testing is extremely valuable in cases of asthma. Look for alpha 1-antitrypsin deficiency in difficult cases. If congestive heart failure is suspected, an arm-to-tongue circulation time would be valuable. A trial of diuretics may also assist in the diagnosis. If reflux esophagitis is suspected, prolonged monitoring of esophageal pH may be diagnostic. A trial of therapy with an H₂ antagonist may also be diagnostic.

» READ BOOK EXCERPT ONLINE »

Source: Algorithmic Diagnosis of Symptoms and Signs, 2003

FEVER, ACUTE: Ask the Following Questions:
(Algorithmic Diagnosis of Symptoms and Signs)

Is there a history of drug ingestion or injection? This will help diagnose drug reactions and serum sickness, which are common and easily discovered in the history. Patients with glucose-6-phosphate dehydrogenase deficiency may develop fever after receiving certain drugs.
Is there a rash? The presence of a rash should make one think of a drug reaction, meningococcemia, the various exanthems, and subacute bacterial endocarditis.
Is there localized pain? If there is a sore throat, obviously streptococcal pharyngitis or a viral URI is likely. If there is headache, meningitis or encephalitis must be considered. If there is chest pain, one should consider a pulmonary infarct, myocardial infarction, or Bornholm disease. If there is abdominal pain, one would consider pyelonephritis, cholecystitis, and appendicitis among the various conditions. If there is joint pain, one should consider rheumatic fever, rheumatoid arthritis, or septic arthritis.
Is there a focal discharge? A productive cough would make one consider pneumonia. A rectal discharge would make one consider a perirectal abscess. A urethral discharge should make one think of gonorrhea.
Are there other localizing signs? Frequency of urination should make one think of pyelonephritis. A productive cough should make one think of pneumonia, whereas jaundice would make one think of hepatitis.

DIAGNOSTIC WORKUP

Routine studies include a CBC, sedimentation rate, chemistry panel, urinalysis, chest x-rays, VDRL test, and tuberculin skin test. Serial blood cultures should be done on all patients. Febrile agglutinins usually should be done. An ASO titer or streptozyme test should be done to exclude rheumatic fever. RNA, ANA, and DNA tests should be done to look for lupus and other connective tissue disease. An HIV antibody titer may need to be ordered.

The next step is to culture any discharge or various body fluids that might be suspect. Thus, a urinalysis and urine culture should be done. A nose and throat culture should be done. A sputum smear and culture may need to be done. The next consideration is to do various serologic tests. A heterophile antibody titer should be done in teenagers. Febrile agglutinin tests may need to be done. Acute and convalescent phase sera for viral studies may need to be done.

Next one should do skin testing. Thus, histoplasmin, coccidioidin, and blastomycin skin testing should be done on patients with a cough. Trichinella skin testing may need to be done, as well as brucellin skin testing. A Kveim test might need to be done for suspected sarcoidosis.

The next step is to do plain x-rays of suspected areas. For instance, x-rays of the teeth may disclose an abscessed tooth. X-rays of the long bones may disclose a metastatic carcinoma.

The next step is contrast x-ray studies of various organ systems. An intravenous pyelogram may show a hypernephroma. A cholecystogram may show gallstones. An upper GI series and barium enema may show chronic pancreatitis or diverticulitis. Angiography may disclose periarteritis nodosa, aortitis or giant cell arteritis.

The next step is to do a CT scan of the abdomen and pelvis. If this is negative, consider a CT scan of the chest and mediastinum. Echocardiography may disclose valvular vegetations or an atrial myxoma.

Next, consider biopsying various organ systems. For instances, a lymph node biopsy may disclose a lymphoma or sarcoidosis. A muscle biopsy may disclose periarteritis nodosa, polymyositis, or trichinella.

Next one should do bone scans and gallium scans for possible metastasis, osteomyelitis, or localized abscesses.

If all these procedures fail to turn up a lesion, then an exploratory laparotomy may need to be done. A fibrin test may indicate Mediterranean fever, or urine for etiocholanolone may also indicate a relapsing type of fever. A urine test for porphobilinogen may diagnose porphyria.

The wisest move is to conduct this investigation with the help of an infectious disease specialist or a specialist in the body organ system most likely suspected of harboring the infection.

» READ BOOK EXCERPT ONLINE »

Source: Algorithmic Diagnosis of Symptoms and Signs, 2003

FEVER, CHRONIC: Ask the Following Questions:
(Algorithmic Diagnosis of Symptoms and Signs)

Is there a history of drug ingestion or injection? Of course, the history should reveal that the patient has been on a certain drug or has received certain antitoxins, serums, or vaccines.
Is there a rash? If there is a rash, one should suspect subacute bacterial endocarditis, Rocky Mountain spotted fever, secondary syphilis, rat-bite fever, pemphigus, a drug reaction, lupus erythematosus, dermatomyositis, or typhoid fever. There are other conditions associated with a rash also.
Is there a characteristic pattern to the fever? The various forms of malaria give a characteristic pattern of the fever, as well as undulant fever in Hodgkin's disease.
Is there localized pain? Abdominal pain should suggest a cholecystitis, hepatic abscess, diverticulitis, etc. A sore throat should suggest infectious mononucleosis, leukemia, and subacute thyroiditis. Joint pain should suggest rheumatoid arthritis, rheumatic fever, or gonococcal arthritis. Earache should suggest otitis media or mastoiditis. Chest pain should suggest tuberculosis, pleurisy, or empyema.
Is there a localized discharge? Purulent sputum should suggest pneumonia, tuberculosis, or chronic fungal disease in the lung. A urethral discharge would suggest gonorrhea or Reiter's disease.
Is there a localized mass or swelling? An abdominal mass would suggest hepatic abscess, pancreatic cyst, or diverticular abscess. A flank mass might suggest hypernephroma or perinephric abscess.

DIAGNOSTIC WORKUP

The diagnostic workup is similar to that for acute fever on page 168 .

» READ BOOK EXCERPT ONLINE »

Source: Algorithmic Diagnosis of Symptoms and Signs, 2003

Fever: Differential Diagnosis
(In a Page: Signs and Symptoms)

Infection is the most common cause
–Viral (e.g., influenza, HIV, hepatitis, herpes simplex encephalitis, mononucleosis, adenovirus)
–Bacterial (e.g., pneumonia, endocarditis, tuberculosis, meningitis, pyelonephritis, appendicitis, cholecystitis, cellulitis)
–Lyme disease
–Malaria
–Syphilis
–Tularemia
–Intra-abdominal abscess

Malignancy
–Lymphoma (Hodgkin's and non-Hodgkin's)
–Lymphoproliferative disorders
–Renal cell carcinoma
–Leukemia
–Hepatocellular carcinoma
Rheumatologic disorders
–Temporal arteritis/giant cell arteritis
–Adult-onset Still's disease
–Systemic lupus erythematosus
–Sarcoidosis
–Rheumatoid arthritis
Drug fever
–Often temporally associated with the initiation of a new medicine
–Often associated with a rash (biopsy reveals leukocytoclastic vasculitis)
–Eosinophilia is common

Pulmonary embolism
–Mild fever is often present
–Other findings of thromboembolic disease (e.g., leg swelling, dyspnea) may be present

Osteomyelitis

Occult abscess

Malignant hypothermia

Workup and Diagnosis

Complete history and physical examination
–In most cases, the cause of fever will be suggested during the history and physical
–Note characteristics of the fever, maximum temperature, presence of diurnal variation, and recent travel
Initial laboratory studies may include CBC with differential, electrolytes, BUN/creatinine, glucose, calcium, urinalysis, urine cultures, liver function tests, and ESR
Blood cultures, including thick smear of the blood to evaluate for parasites (e.g., malaria)
Chest X-ray may reveal focus of infection (e.g., pneumonia, tuberculosis, malignancy)
Lumbar puncture for CSF analysis may be indicated
CT scan of chest and abdomen may reveal an occult infection, abscess, or malignancy
Echocardiogram is indicated if suspect infective endocarditis or aortitis (syphilis)
Tagged white cell scans may be used to localize abscess
Bone marrow biopsy may be indicated if leukemia or a myelodysplastic syndrome is suspected

» READ BOOK EXCERPT ONLINE »

Source: In a Page: Signs and Symptoms, 2004

Cough - Nonproductive: Differential Diagnosis
(In a Page: Signs and Symptoms)

Smoker's cough
Postnasal drip (e.g., chronic sinusitis, allergic rhinitis)
–Most common cause of chronic cough in nonsmokers

GERD
–Second most common cause of chronic cough in nonsmokers

Asthma/reactive airway disease
–Classic triad of chronic cough, dyspnea, and wheezing

ACE inhibitor use

Acute bronchitis
–Most commonly caused by viruses (e.g., influenza, adenovirus, rhinovirus, RSV)
–Postviral bronchitis may last beyond 6 weeks

Pneumonia
–“Typical” pneumonia (e.g., Streptococcus pneumoniae, Haemophilus influenzae, or influenza/parainfluenza viruses) is characterized by acute or subacute onset of fever, dyspnea, fatigue, pleuritic chest pain, and cough
–“Atypical” pneumonia (e.g., Mycoplasma, Legionella, Chlamydia) is characterized by more gradual onset, dry cough, headache, fatigue, and minimal lung signs

Aspirated foreign body
–Abrupt onset of unilateral wheezing or stridor, cough, decreased breath sounds
–Leading cause of home accidental death in children younger than 6 (boys >girls)

Lung cancer
–90% of cases due to smoking (other risk factors include radon, asbestos, pollutants)

COPD (emphysematous variant)

Sarcoidosis

Cryptogenic organizing pneumonia
–Most commonly occurs following viral infection or exposure

Congestive heart failure

Filarial disease

Aspiration

Workup and Diagnosis

Complete history and physical examination
–Note acute (<3 weeks) versus chronic or recurrent
Initial tests may include CBC, pulse oximetery, ESR, peak flow measurements, PPD, and eosinophil count
Chest X-ray and/or CT if patient has concerning symptoms (e.g., weight loss, hemoptysis, fever)
Consider blood and sputum cultures
Initial empiric treatment of postnasal drip (antihistamine, decongestant, nasal steroids), asthma (trial of bronchodilators or a methacholine challenge test), and/or GERD (proton pump inhibitor) may be advisable
If imaging is normal and empiric treatment for GERD does not resolve symptoms, proceed with upper GI endoscopy or esophageal pH monitoring
Consider CT of sinuses or nasolaryngoscopy to evaluate for sinusitis
Consider bronchoscopy to identify subtle pulmonary causes
Consider cardiac workup if pulmonary and GI evaluations are negative

» READ BOOK EXCERPT ONLINE »

Source: In a Page: Signs and Symptoms, 2004

Cough - Productive: Differential Diagnosis
(In a Page: Signs and Symptoms)

Postnasal drip (e.g., chronic sinusitis, allergic rhinitis)
–Most common cause of chronic cough in nonsmokers
Acute bronchitis
–Most commonly caused by viruses (e.g., influenza, adenovirus, rhinovirus, RSV)
–Bacteria are much less common (e.g., Streptococcus pneumoniae, Mycoplasma, Haemophilus influenzae)
Pneumonia
–May be community-acquired, hospital-acquired, or due to aspiration
–“Typical” pneumonia (e.g., S. pneumoniae, H. influenzae, influenza virus) has acute or subacute onset of fever, dyspnea, fatigue, pleuritic chest pain, and productive cough
–“Atypical” pneumonia (e.g., Mycoplasma, Legionella, Chlamydia, Pneumocystis carinii) has more gradual onset, dry cough, headache, fatigue
Smoker's cough

Lung cancer
–90% of cases due to smoking (other risk factors include radon, asbestos, pollutants)
Asthma with secondary infection
COPD (chronic bronchitis component)
Congestive heart failure
–Associated with “frothy” sputum
Tuberculosis

Workup and Diagnosis

Complete history and physical examination
–Note acute (<3 weeks) versus chronic or recurrent
Initial tests may include CBC, pulse oximetry, ESR, peak flow measurements, PPD, chest X-ray, blood cultures, sputum Gram stain and culture, and acid-fast stain for tuberculosis
Pulmonary function tests with or without methacholine challenge
Chest CT and/or sputum cytology if patient has concerning symptoms (e.g., weight loss, hemoptysis, fever)
Initial empiric treatment for postnasal drip (antihistamine, decongestant, nasal steroids)
Consider CT of sinuses or nasolaryngoscopy to evaluate for sinusitis
Consider bronchoscopy with possible bronchoalveolar lavage and/or biopsy

» READ BOOK EXCERPT ONLINE »

Source: In a Page: Signs and Symptoms, 2004

Rash with Fever: Differential Diagnosis
(In a Page: Signs and Symptoms)

Viral exanthems
–Leading cause of fever and rash in childhood
–Most children present with low-grade fevers, viral prodromal symptoms, and a secondary diffuse exanthem that is usually nonspecific and morbilliform
–Often last only a few days and requires only supportive management
Drug reactions
–Account for a large portion of rashes with associated fever
–Immune complex disease or serum sickness has been reported with many medications
Meningococcemia
–Most common under age 1
–After a brief prodrome; onset is abrupt with spiking fevers, diffuse purpuric lesions, delirium, and death
–DIC and purpura fulminans with secondary necrosis of digits and limbs can occur

Rocky Mountain Spotted Fever
–A fulminant and deadly rickettsial disease transmitted by a tick bite
–Only 60% of patients are aware of tick bite
–Characteristic rash starts acrally on wrists and ankles and spreads toward the trunk
–Initially, pink macules evolve over 10–24 hours into red papules, then purpuric macules and violaceous patches involving most of the body surface area
–Necrosis and DIC may occur
Toxic shock syndrome, Staphylococcus aureus, and streptococcal diseases
–Most cases due to toxin production
–Rapid onset of fever, hypotension with generalized skin (palms and soles common) and mucous membrane erythema (“erythroderma” in case definition), and subsequent multiorgan failure
–Palmar/solar desquamation in 1–3 weeks
–A morbilliform rash and skin “pain” or hyperesthesia is common
–Nonsurgical and surgical wounds are often the source of infection in the more common nonmenstrual variant of TSS

Fifth disease
Measles
Rubella
Parvovirus
Varicella

Workup and Diagnosis

Because of a seemingly endless list of possible etiologies for fever and rash, a focused history and physical exam are essential to a quick, accurate diagnosis
Determine whether the patient appears toxic; age and presence of co-morbid conditions aid diagnosis
If there is any evidence of purpura;
–Quickly consider the diagnosis of RMSF, meningococcemia, or systemic vasculitis
–In the cases of meningococcemia and RMSF, the diagnosis must be made empirically, then later confirmed so that therapy is immediately initiated

Obtain bacterial cultures from any wounds, culture the pharynx if indicated, and consider skin biopsy and culture; blood cultures are indicated in toxic patients; consider immediate lumbar puncture for CSF culture and Gram stain if meningococcemia is suspected

Acute and convalescent antibody titers can confirm RMSF; skin biopsy with immunofluorescnce may demonstrate a vasculitis with visible rickettsial organisms within the endothelium

TSS is often diagnosed by history and examination alone; recent cutaneous injury and nonspecific morbilliform rash in a hypotensive patient in association with the presence of epidermal necrosis on skin biopsy can confirm the diagnosis; wound cultures with growth of staph or strep

» READ BOOK EXCERPT ONLINE »

Source: In a Page: Signs and Symptoms, 2004

Fever – Cyclic: Differential Diagnosis
(In A Page: Pediatric Signs and Symptoms)

PFAPA, or Marshall syndrome
–Periodic fever (usually high, 104°F [40°C]), aphthous stomatitis, pharyngitis, and adenitis
–Most common diagnosis for true cyclic fever, usually in children <5 years
–Recurs every 3–4 weeks

Cyclic neutropenia
–Periodic fever, average cycle of 21 days
–Pharyngitis, mouth ulcers, and lymphadenopathy are also noted
–May not be associated with infection

Infectious diseases
–Relapsing fever due to Borrelia recurrentis,
relapses every 10–14 days
–EBV may occur at 6–8 week intervals

Familial Mediterranean fever
–Brief attacks of fever and serositis
–Autosomal recessive disease
–Sephardic Jews, Arabs, Turks, and Armenians commonly affected
–50% have onset before 10 years of age
–May occur in regular 7–28-day intervals
–Amyloidosis is a possible complication

Hyper-IgD and periodic fever syndrome (HIDS)
–High fevers, abdominal pain, cervical lymphadenopathy, sometimes diarrhea and arthritis, in early infancy
–Autosomal recessive, most patients from Western Europe (French, Dutch)
–Cycles may be regular every 14–28 days
- TNF-receptor-associated periodic syndrome (TRAPS) or Hibernian fever
  –Fever, myalgias with migratory pattern, conjunctivitis and rash
  –Autosomal dominant
  –first described in Irish/Scottish individuals but other ethnic groups involved
  –Amyloidosis is a possible complication (25% of untreated individuals)
- Factitious fever
Workup and Diagnosis
- History
  –Age of onset, duration of episodes, duration of symptom-free periods, associated symptoms (pharyngitis, aphthous ulcers)
  –Lymphadenopathy, abdominal pain
  –Family history of cyclic fever, ethnicity
  –Exposure to ticks (woods, camping), travel history
>

» READ BOOK EXCERPT ONLINE »

Source: In A Page: Pediatric Signs and Symptoms, 2007

Fever – Recurrent: Differential Diagnosis
(In A Page: Pediatric Signs and Symptoms)

Repeated viral infections
–Most common cause of recurrent febrile episodes in childhood
–Start of day care or change of geographic location may be related

Urinary tract infection (UTI)
–May be self-limited but recur especially if underlying anomaly exists

Epstein-Barr virus (EBV)
–May present with recurrent febrile episodes due to one initial infection

Other specific viral syndromes
–Parvovirus B19
–CMV

Immunodeficiency
–Repeated bacterial infections should lead to investigation of immune status

Dental abscess (non-dental abscesses typically present with prolonged daily fever)
Chronic meningococcemia
Acute rheumatic fever
Inflammatory bowel disease (IBD)
Juvenile rheumatoid arthritis (JRA)
Behçet disease

Tumor necrosis factor receptor-associated periodic syndrome (TRAPS) or Hibernian Fever
–Autosomal dominant disease with fever, myalgias with migratory pattern, conjunctivitis and rash

Familial cold autoinflammatory syndrome or familial cold urticaria
–Rash, fever, arthralgia, and conjunctivitis
–Precipitated by exposure to cold

Muckle-Wells syndrome
–Similar presentation to familial cold urticaria
–Symptoms not triggered by cold

Brucellosis
–Most prevalent around the Mediterranean and Arabic countries, also present in South America and India

Yersiniosis
Typhoid fever
Rat-bite fever
Malaria
Factitious fever

Workup and Diagnosis

History
–Documentation of fever
–Duration of episodes and fever-free intervals
–Symptoms associated with the fever
–Symptoms during the fever-free intervals
–Weight loss
–Recent documented infections, medications
–Travel, animal and insect exposure
–Specific conditions related to episodes (e.g., cold)

Physical exam
–Vitals, growth parameters (failure to thrive can be a presentation of UTI and immunodeficiency)
–Rash (transient pink rash in JRA)
–Ophthalmologic exam: Uveitis (IBD and Behçet), conjunctivitis (TRAPS)
–Hepatosplenomegaly, lymphadenopathy
–Genital ulcers (Behçet)
–Perianal skin tags (IBD)
–Mouth ulcers, pharyngitis
–Arthritis

CBC with differential
ESR or CRP
Urine culture
Blood culture
Serology for EBV, CMV, or Parvovirus B19
Low levels of serum type 1 TNF receptor in TRAPS
Documentation of fever in the office should exclude the possibility of factitious fever

» READ BOOK EXCERPT ONLINE »

Source: In A Page: Pediatric Signs and Symptoms, 2007

Fever – Unknown Origin: Differential Diagnosis
(In A Page: Pediatric Signs and Symptoms)

Infections (40%)
–Infectious mononucleosis (EBV, CMV)
–Other systemic viral syndromes (e.g., HIV)
–UTI (e.g., E. coli)
–Osteomyelitis (e.g., staphylococcus)
–Upper and lower respiratory infections (sinusitis, mastoiditis, pneumonia)
–Cat-scratch disease (Bartonella henselae)
–Tuberculosis, nontuberculous mycobacterial infections
–Abscess (abdominal or retroperitoneal)
–CNS infections
–Endocarditis (subacute)
–Salmonellosis
–Lyme disease (Borrelia burgdorferi)
–Leptospirosis
–Congenital syphilis
–Others: Brucellosis, histoplasmosis, leishmaniasis, yersiniosis, Q fever (Coxiella burnetii), Rocky Mountain spotted fever (Rickettsia rickettsii)

Autoimmune diseases (15%)
–Rheumatoid arthritis accounts for 3/4 of FUO due to autoimmune diseases
–Systemic lupus erythematosus
–Rheumatic fever
–Vasculitis (e.g., HSP)
–Sarcoidosis

Neoplastic diseases (7%)
–Leukemia/lymphoma accounts for 80% of
FUO due to malignancies
–Neuroblastoma
–Hepatoma
–Soft tissue sarcoma

Inflammatory bowel disease (3%)
Drugs and nutritional supplements (drug fever)
Factitious fever
Munchausen by proxy
Neurologic disorders
–Familial dysautonomia
–Central thermoregulatory disorder
–Head injury
Hyperthyroidism
Anhidrotic ectodermal dysplasia
Diabetes insipidus
Kikuchi disease

Workup and Diagnosis

History
–Differentiate between FUO and multiple febrile
illnesses that occur in short period of time
–Daily documentation of fever, onset, duration
–Weight loss, diet history, medications, sick contacts
–Animal or tick exposure, travel, foreign contacts
–Immune status, history of transfusion, surgery
–FH of autoimmune or neoplastic diseases

Physical exam
–Vital signs, growth parameters
–Skin (rash, desquamation, jaundice)
–Ophthalmologic exam (conjunctivitis, uveitis)
–Oral lesions
–Cardiologic exam (new onset murmur)
–Abdominal exam (masses, hepatosplenomegaly)
–Testicular exam
–Muscle tenderness, bone tenderness, arthritis
–Lymphadenopathy
–Neurologic exam

Labs
–CBC, ESR, C-reactive protein
–Renal and hepatic function tests, albumin and globulin
–Urinalysis, blood and urine culture
–Viral titers, PPD, cultures for specific organisms, ASO, ANA, bone marrow

Radiographic imaging with plain films, ultrasound, bone scan, CT scan or MRI of specific organ systems as warranted by the history and physical exam

» READ BOOK EXCERPT ONLINE »

Source: In A Page: Pediatric Signs and Symptoms, 2007

Cough – Acute: Differential Diagnosis
(In A Page: Pediatric Signs and Symptoms)

Upper airway disease
–URI or common cold accounts for much pediatric coughing (influenza, parainfluenza, rhinovirus)
–Chronic sinusitis, tonsillitis, laryngitis, and croup are other common infections
–Allergic disease
–Vocal cord dysfunction (VCD)

Lower airway disease
–Asthma is inflammatory triad of edema, mucus, and bronchospasm, characterized by reversibility with asthma drugs (the most common triggers for asthma are viral disease, irritants such as ETS, allergic disease, and gastroesophageal reflux)
–Infectious diseases: Bronchiolitis, caused by RSV in babies, causes cough from inflammatory changes and debris; bronchitis is more common in older children and may be secondary to smoking or ETS exposure; other viral lower airway diseases include adenovirus, influenza, and parainfluenza
–Foreign body aspiration
–Chronic diseases (e.g., cystic fibrosis and bronchiectasis) and structural abnormalities (e.g., PCD, TEF, or cleft, rings, and slings) may present with intermittent rather than chronic cough

Parenchymal and pleural disease
–Infectious diseases account almost exclusively for all parenchymal and pleural causes of cough (i.e., pneumonia and empyema)
–Usual infectious agents include bacterial disease (e.g., streptococcal, staphylococcal) and atypical pneumonias (e.g., Mycoplasma pneumoniae), TB
–Irritation of a branch of cranial nerve ten in the external auditory canal can trigger cough

Workup and Diagnosis

History
–What started it? History (e.g., infection or FB aspiration) may suggest a mechanism
–What makes it worse? Activity leading to cough may suggest asthma or structural disease; seasonal onset suggests allergic disease; night cough suggests GER
–Is the cough productive? Infection is the primary cause of sputum production; also consider asthma, bronchiectasis, smoking, or CF

Physical exam
–Loud, “brassy,” vibrato, honking quality suggests tracheomalacia
–High-pitched stridor suggests a fixed tracheal obstruction (ring, sling, FB, subglottic stenosis)
–Violent paroxysms with an inspiratory whoop suggests pertussis syndrome
–A productive, “wet” cough suggests bronchitis or pneumonia
–A wheezy, “tight” cough suggests asthma

Studies
–CXR may demonstrate an atypical pneumonia
–Pulmonary function tests to diagnose asthma or large airway obstruction
–Bronchoscopy and lavage to diagnose malacia, infection, FB, VCD
–V/Q scan may diagnose a pulmonary embolus (rare)

Exercise testing may provoke symptoms of exercise-induced asthma or VCD

» READ BOOK EXCERPT ONLINE »

Source: In A Page: Pediatric Signs and Symptoms, 2007

Cough – Chronic: Differential Diagnosis
(In A Page: Pediatric Signs and Symptoms)

Lower airway disease
–Asthma
–Inflammatory triad of edema, mucus, and bronchospasm, characterized by reversibility with asthma drugs
–The most common triggers for asthma are viral disease, irritants (e.g., ETS), allergic disease, and GER
–Airway infections: Bronchiolitis, caused by RSV in babies, may cause chronic cough from persistent inflammatory change and debris; bronchitis is more common in older children and may be secondary to smoking or ETS exposure
–Foreign body: Associated with endobronchial infection and damage
–Cystic fibrosis: The most common life-threatening inherited illness of whites, is associated with production of chronically infected sputum
–Bronchiectasis: Chronic infection and damage to the airway; may be secondary to another disease (e.g., TB or CF)
–Structural abnormalities: PCD, TEF, or cleft, rings, slings

Upper airway disease
–Infectious diseases: Chronic sinusitis, tonsillitis, laryngitis, including that secondary to GER (although acute disorders, the inflammation from URI may be associated with a chronic cough if frequent enough)

Parenchymal and pleural disease
–Infectious disease accounts almost exclusively for all parenchymal and pleural causes of cough (e.g., pneumonia and empyema)
- CNS causes
  –CNS causes of cough include “habit cough” (or psychogenic cough), Tourette disease associated “cough tic” or throat clearing, VCD
  –Irritation of a branch of cranial nerve ten in the external auditory canal can trigger chronic cough
Workup and Diagnosis
- History
  –Cough lasting longer than 2–6 weeks suggests either a predisposing factor (e.g., bronchomalacia) or an ongoing trigger (e.g., asthma)
  –An acute lung or airway injury (i.e., infection or FB) suggests a mechanism for chronic cough
  –An insidious onset is more consistent with a chronic underlying condition (i.e., CF, TB, GER)
  –Seasonal change suggests allergic disease
  –Night cough suggests GER
  –A positive response to asthma therapy suggests asthma
  –Antibiotic responsiveness suggests chronic infection (i.e., CF, bronchiectasis, sinusitis)
  –Distractability suggests habit cough, as may a lack of coughing while asleep
  –Is the cough productive? Culture sputum and consider asthma, bronchiectasis, smoking, or CF
- Physical exam: Loud, “brassy,” vibrato, honking quality suggests tracheomalacia; high-pitched stridor suggests a fixed tracheal obstruction (ring, sling, FB, subglottic stenosis); violent paroxysms with an inspiratory whoop suggest pertussis syndrome
- Studies: Chest films often not diagnostic; PFT to diagnose asthma or large airway obstruction; bronchoscopy and lavage to diagnose malacia, infection, FB, VCD
- Exercise testing may provoke symptoms of EIA or VCD

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Source: In A Page: Pediatric Signs and Symptoms, 2007

Fever – Acute: Differential Diagnosis
(In A Page: Pediatric Signs and Symptoms)

Viral infections
–Account for the majority of febrile illnesses (FI) in infancy and childhood
–Upper respiratory infections (e.g., parainfluenza virus)
–Lower respiratory infections (e.g., RSV)
–Non-bacterial gastroenteritis (e.g., rotavirus)
–Aseptic meningitis (e.g., enterovirus)

Bacterial infections
–UTIs account for 1.7% of FI in children 5 years and 7.5% in infants <8 weeks
–Pneumonia (e.g., group A streptococcus)
–Bacteremia (2% of FI in all children, highest rates seen in younger infants)
–Meningitis (0.8% of FI in all children)
–In febrile neonates, the overall rate of serious bacterial infections (SBI) is ~13%
Vaccine reaction
- Collagen vascular diseases
  –Kawasaki disease: 3,000 cases per year in the U.S., rates higher in Asia, 80% of cases occur in children <5 years
  –Henoch-Schönlein purpura: Low-grade fever is present in 50% of cases
  –Juvenile rheumatoid arthritis: Incidence 1/10,000
  –SLE
  –Acute rheumatic fever
- Malignancy
  –Leukemia: Most common childhood malignancy; early symptoms include fever, fatigue, pallor, anemia, bone pain
  –Lymphoma
  –Solid tumors (neuroblastoma, sarcoma)
- Inflammatory bowel disease
  –Diarrhea, pain, fever, blood loss
  –Crohn disease, ulcerative colitis
- Tissue injury (trauma, hematoma, burns)
- Drug reaction
- Biologic agents (blood products, gamma-globulin)
- Endocrinologic disorders
  –Thyrotoxicosis
  –Pheochromocytoma
- Genetic diseases
  –Familial Mediterranean fever
- Factitious fever
Workup and Diagnosis
- Physical exam
  –Temperature: Rectal preferred for infants <3 months
  –Vitals: Relative brady- or tachycardia, tachypnea
  –Growth parameters especially if frequent febrile episodes/infections (immunodeficiency)
  –Appearance, irritability, quality of cry, consolability
  –Skin (color, rash, desquamation), conjunctivitis, ocular or nasal discharge, mouth lesions, throat and ear exam
  –Lymphadenopathy, abdominal exam, neuro exam
  –Joint exam (arthritis), muscle tenderness
  - Immunologic workup and/or bone marrow for prolonged fever and/or other clinical evidence
  >>>>

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Source: In A Page: Pediatric Signs and Symptoms, 2007

COUGH: Approach to the Diagnosis
(Differential Diagnosis in Primary Care)

Clinically, exposure to dust, smoke, and various gases should be looked for in the patient presenting with a cough. An allergic history (e.g., hay fever) is important. Careful exclusion of cardiovascular disease should be done, especially when sputum is negative for routine cultures, tuberculosis, fungi, and Papanicolaou smears and chest x-rays, bronchoscopy, and bronchography are normal. Hysterical cough should be considered, however, as well as reflux esophagitis and hiatal hernia. A sputum and nasal smear for eosinophils should be done to rule out asthma. A trial of therapy may be indicated.

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Source: Differential Diagnosis in Primary Care, 2007

FEVER: Approach to the Diagnosis
(Differential Diagnosis in Primary Care)

There are certain things to remember when a patient with fever is approached. First, a mild elevation up to 100.5°F (38°C) rectally may be normal in some people. Second, one should rule out malingering by the patient or incorrect recording by hospital personnel. Finally, psychogenic disorders must be ruled out.

The duration and severity of the fever are important. If possible, a careful chart of the fever should be made with the patient off all drugs (especially aspirin and steroids). Conditions with intermittent or relapsing fever such as brucellosis, malaria, and Mediterranean fever will be elucidated in this fashion (Table 28).

The association with other symptoms is important. Fever, right upper quadrant pain, and jaundice suggest cholecystitis or cholangitis, whereas fever with right-sided flank pain suggests pyelonephritis. After taking a few moments to jot down the differential before launching into the history and physical examination, one can question and examine the patient more appropriately. The differential diagnosis will also lead to more appropriate use of laboratory testing.

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Source: Differential Diagnosis in Primary Care, 2007

Fever: History and physical examination
(Handbook of Signs & Symptoms (Third Edition))

If the patient’s fever is only mild to moderate, ask him when it began and how high his temperature reached. Did the fever disappear, only to reappear later? Did he experience other symptoms, such as chills, fatigue, or pain?

Obtain a complete medical history, noting especially immunosuppressive treatments or disorders, infection, trauma, surgery, diagnostic testing, and the use of anesthesia or other medications. Ask about recent travel because certain diseases are endemic.

Let the history findings direct your physical examination. Because a fever can accompany diverse disorders, the examination may range from a brief evaluation of one body system to a comprehensive review of all systems. (SeeHow fever develops.)

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Source: Handbook of Signs & Symptoms (Third Edition), 2006

Cough, barking: History and physical examination
(Handbook of Signs & Symptoms (Third Edition))

Ask the child's parents when the barking cough began and what other signs and symptoms accompanied it. When did the child first appear to be ill? Has he had previous episodes of croup syndrome? Did his condition improve upon exposure to cold air?

Spasmodic croup and epiglottiditis typically occur in the middle of the night. The child with spasmodic croup has no fever, but the child with epiglottiditis has a sudden high fever. An upper respiratory tract infection typically is followed by laryngotracheobronchitis.

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Source: Handbook of Signs & Symptoms (Third Edition), 2006

Cough, nonproductive: History and physical examination
(Handbook of Signs & Symptoms (Third Edition))

Ask the patient when his cough began and whether body position, the time of day, or a specific activity affects it. How does the cough sound — harsh, brassy, dry, or hacking? Try to determine if the cough is related to smoking or a chemical irritant. If the patient smokes or has smoked, note the number of packs smoked daily multiplied by years (“pack-years”). Next, ask about the frequency and intensity of the coughing. If he has pain associated with coughing, breathing, or activity, when did it begin? Where is it located?

Ask the patient about recent illness (especially a cardiovascular or pulmonary disorder), surgery, or trauma. Also ask about hypersensitivity to drugs, foods, pets, dust, or pollen. Find out which medications the patient takes, if any, and ask about recent changes in schedule or dosages. Also, ask about recent changes in his appetite, weight, exercise tolerance, or energy level and recent exposure to irritating fumes, chemicals, or smoke.

As you're taking his history, observe the patient's general appearance and manner: Is he agitated, restless, or lethargic; pale, diaphoretic, or flushed; anxious, confused, or nervous? Also, note whether he's cyanotic or has clubbed fingers or peripheral edema.

CULTURAL CUE: Because of the fear of being known as someone with tuberculosis (TB), the patient may be reluctant to provide information about his signs and symptoms such as a cough. Ask the patient at risk for TB — one born in another country, in contact with acute TB, or with high-risk behaviors — about potential TB exposure.

Next, perform a physical examination. Start by taking the patient's vital signs. Check the depth and rhythm of his respirations, and note if wheezing or “crowing” noises occur with breathing. Feel the patient's skin: Is it cold or warm; clammy or dry? Check his nose and mouth for congestion, inflammation, drainage, or signs of infection. Inspect his neck for distended jugular veins and tracheal deviation, and palpate for masses or enlarged lymph nodes.

Examine his chest, observing its configuration and looking for abnormal chest wall motion. Do you note any retractions or use of accessory muscles? Percuss for dullness, tympany, or flatness. Auscultate for wheezing, crackles, rhonchi, pleural friction rubs, and decreased or absent breath sounds. Finally, examine his abdomen for distention, tenderness, masses, or abnormal bowel sounds.

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Source: Handbook of Signs & Symptoms (Third Edition), 2006

Cough, productive: History and physical examination
(Handbook of Signs & Symptoms (Third Edition))

When the patient's condition permits, ask when the cough began, and find out how much sputum he's coughing up each day. (The normal tracheobronchial tree can produce up to 3 oz [89 ml] of sputum per day.) At what time of day does he cough up the most sputum? Does his sputum production have any relationship to what or when he eats or to his activities or environment? Ask him if he has noticed an increase in sputum production since his coughing began. This may result from external stimuli or from such internal causes as chronic bronchial infection or a lung abscess. Also ask about the color, odor, and consistency of the sputum. Blood-tinged or rust-colored sputum may result from trauma due to coughing or from an underlying condition, such as a pulmonary infection or a tumor. Foul-smelling sputum may result from an anaerobic infection, such as bronchitis or a lung abscess.

How does the cough sound? A hacking cough results from laryngeal involvement, whereas a “brassy” cough indicates major airway involvement. Does the patient feel pain associated with his productive cough? If so, ask about its location and severity and whether it radiates to other areas. Does coughing, changing body position, or inspiration increase or help relieve his pain?

Next, ask the patient about his cigarette, drug, and alcohol use and whether his weight or appetite has changed. Find out if he has a history of asthma, allergies, or respiratory disorders, and ask about recent illnesses, surgery, or trauma. What medications is he taking? Does he work around chemicals or respiratory irritants such as silicone?

Examine the patient's mouth and nose for congestion, drainage, or inflammation. Note his breath odor; halitosis can be a sign of pulmonary infection. Inspect his neck for distended veins, and palpate for tenderness and masses or enlarged lymph nodes. Observe his chest for accessory muscle use, retractions, and uneven chest expansion, and percuss for dullness, tympany, or flatness. Finally, auscultate for a pleural friction rub and abnormal breath sounds — rhonchi, crackles, or wheezes. (See Productive cough: Common causes and associated findings, page 168.)

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Source: Handbook of Signs & Symptoms (Third Edition), 2006

Respiratory syncytial virus infection: Diagnosis
(Professional Guide to Diseases (Eighth Edition))

Diagnosis is usually based on clinical findings and epidemiologic information.

❑Many facilities can perform rapid tests for the virus using fluid obtained from the nose.

❑Cultures of nasal and pharyngeal secretions may show RSV; however, the virus is labile, so cultures aren't always reliable.

❑Chest X-rays help detect pneumonia.

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Source: Professional Guide to Diseases (Eighth Edition), 2005

Acute respiratory failure in COPD: Diagnosis
(Professional Guide to Diseases (Eighth Edition))

Progressive deterioration in ABG levels and pH, when compared with the patient’s “normal” values, strongly suggests ARF in COPD. (In patients with essentially normal lung tissue, pH below 7.35 usually indicates ARF, but patients with COPD display an even greater deviation from this normal value, as they do with PaCO₂ and PaO₂.)

Other supporting findings include:

❑ Bicarbonate — Increased levels indicate metabolic alkalosis or reflect metabolic compensation for chronic respiratory acidosis.

❑ Hematocrit (HCT) and Hb — Abnormally low levels may be due to blood loss, indicating decreased oxygen-carrying capacity. Elevated levels may occur with chronic hypoxemia.

❑ Serum electrolytes — Hypokalemia and hypochloremia may result from diuretic and corticosteroid therapies used to treat ARF.

❑ White blood cell count — Count is elevated if ARF is due to bacterial infection; Gram stain and sputum culture can identify pathogens.

❑ Chest X-ray — findings identify pulmonary pathologic conditions, such as emphysema, atelectasis, lesions, pneumothorax, infiltrates, or effusions.

❑ Electrocardiogram — Arrhythmias commonly suggest cor pulmonale and myocardial hypoxia.

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Source: Professional Guide to Diseases (Eighth Edition), 2005

Infant respiratory distress syndrome: Diagnosis
(Professional Guide to Diseases (Eighth Edition))

CONFIRMING DIAGNOSIS Although signs of respiratory distress in a premature neonate during the first few hours of life strongly suggest IRDS, a chest X-ray and arterial blood gas (ABG) analysis are necessary to confirm the diagnosis.

❑ Chest X-ray may be normal for the first 6 to 12 hours (in 50% of neonates with IRDS), but 24 hours after birth it will show the characteristic ground-glass appearance and air bronchograms.

❑ ABG analysis shows decreased partial pressure of arterial oxygen; normal, decreased, or increased partial pressure of arterial carbon dioxide; and decreased pH (from respiratory or metabolic acidosis or both).

❑ Chest auscultation reveals normal or diminished air entry and crackles (rare in early stages).

When a cesarean delivery is necessary before 36 weeks’ gestation, amniocentesis enables the determination of the lecithin/sphingomyelin (L/S) ratio and the presence of phosphatidylglycerol. An L/S ratio of more than 2:1 and the presence of phosphatidylglycerol decrease the likelihood of IRDS.

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Source: Professional Guide to Diseases (Eighth Edition), 2005

Colorado tick fever: Diagnosis
(Professional Guide to Diseases (Eighth Edition))

CONFIRMING DIAGNOSIS A history of recent exposure to ticks along with moderate to severe leukopenia, complement fixation tests, or virus isolation confirm the diagnosis.

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Source: Professional Guide to Diseases (Eighth Edition), 2005

Lassa fever: Diagnosis
(Professional Guide to Diseases (Eighth Edition))

CONFIRMING DIAGNOSIS Isolation of the Lassa virus from throat washings, pleural fluid, or blood confirms the diagnosis.

Recent travel to an endemic area and specific antibody titer support the diagnosis.

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Source: Professional Guide to Diseases (Eighth Edition), 2005

Relapsing fever: Diagnosis
(Professional Guide to Diseases (Eighth Edition))

CONFIRMING DIAGNOSIS Diagnosis requires demonstration of the spirochetes in peripheral blood smears during febrile periods, using Wright's or Giemsa stain.

Borrelia spirochetes may be more difficult to detect in later relapses because their number declines in the blood. In such cases, injecting the patient's blood or tissue into a young rat and incubating the organism in the rat’s blood for 1 to 10 days commonly allows spirochete identification.

In severe infection, spirochetes are found in the urine and cerebrospinal fluid. Other abnormal laboratory results usually include a white blood cell (WBC) count as high as 25,000/µl, with increases in lymphocytes and erythrocyte sedimentation rate; however, the WBC count may be normal. Because the Borrelia organism is a spirochete, relapsing fever may cause a false-positive test for syphilis in 5% to 10% of cases.

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Source: Professional Guide to Diseases (Eighth Edition), 2005

Rheumatic fever and rheumatic heart disease: Diagnosis
(Professional Guide to Diseases (Eighth Edition))

Diagnosis depends on recognition of one or more of the classic symptoms (carditis, rheumatic fever without carditis, polyarthritis, chorea, erythema marginatum, or subcutaneous nodules) and a detailed patient history. Laboratory data support the diagnosis:

❑ White blood cell count and erythrocyte sedimentation rate may be elevated (during the acute phase); blood studies show slight anemia due to suppressed erythropoiesis during inflammation.

❑ C-reactive protein is positive (especially during acute phase).

❑ Cardiac enzyme levels may be increased in severe carditis.

❑ Antistreptolysin-O titer is elevated in 95% of patients within 2 months of onset.

❑ Electrocardiogram changes aren’t diagnostic; but PR interval is prolonged in 20% of patients.

❑ Chest X-rays show normal heart size (except with myocarditis, heart failure, or pericardial effusion).

❑ Echocardiography helps evaluate valvular damage, chamber size, and ventricular function.

❑ Cardiac catheterization evaluates valvular damage and left ventricular function in severe cardiac dysfunction.

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Source: Professional Guide to Diseases (Eighth Edition), 2005

Rocky Mountain spotted fever: Diagnosis
(Professional Guide to Diseases (Eighth Edition))

CONFIRMING DIAGNOSIS Diagnosis is usually based on a history of tick bite or travel to a tick-infested area and a positive complement fixation test (which shows a fourfold increase in convalescent antibody titer compared with acute titers). Blood cultures or skin biopsy at the rash site should be performed to isolate the organism and confirm the diagnosis.

Another common but less reliable antibody test is the Weil-Felix reaction, which also shows a fourfold increase between the acute and convalescent sera titer levels. Increased titers usually develop after 10 to 14 days and persist for several months.

Additional recommended laboratory tests consist of a platelet count for thrombocytopenia (12,000 to 150,000/µl) and a white blood cell count (elevated to 11,000 to 33,000/µl) during the second week of illness.

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Source: Professional Guide to Diseases (Eighth Edition), 2005

Whooping cough: Diagnosis
(Professional Guide to Diseases (Eighth Edition))

Classic clinical findings, especially during the paroxysmal stage, suggest this diagnosis; laboratory studies will confirm it. Nasopharyngeal swabs and sputum cultures show B. pertussis only in the early stages of this disease; fluorescent antibody screening of nasopharyngeal smears provides quicker results than cultures but is less reliable. In addition, the white blood cell (WBC) count is usually increased, especially in children older than age 6 months and early in the paroxysmal stage. Sometimes, the WBC count may reach 175,000 to 200,000/µl, with 60% to 90% lymphocytes.

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Source: Professional Guide to Diseases (Eighth Edition), 2005

Introduction: Respiratory Disorders: Diagnostic tests
(Professional Guide to Diseases (Eighth Edition))

Diagnostic tests evaluate physiologic characteristics and pathologic states within the respiratory tract.

Noninvasive tests include:

❑ Chest X-ray shows such conditions as atelectasis, pleural effusion, infiltrates, pneumothorax, lesions, mediastinal shifts, pulmonary edema, and chronic obstructive pulmonary disease (COPD).

❑ Computed tomography scan provides a three-dimensional picture that’s 100 times more sensitive than a chest X-ray.

❑ Magnetic resonance imaging identifies obstructed arteries and tissue perfusion, but movement of the heart and lungs reduces the image’s clarity.

❑ Sputum specimen analysis assesses sputum quantity, color, viscosity, and odor; microbiological stains and culture of sputum can identify infectious organisms; and cytologic preparations can detect respiratory tract neoplasms. Sensitivity tests determine antibiotic sensitivity and resistance.

❑ Pulmonary function tests measure lung volume, flow rates, and compliance. Normal values, individualized by body stature and age, are reported in percentage of the normal predicted value. Static measurements are volume measurements that include tidal volume, volume of air contained in a normal breath; functional residual capacity, volume of air remaining in the lungs after normal expiration; vital capacity, volume of air that can be exhaled after maximal inspiration; residual volume, air remaining in the lungs after maximal expiration; and total lung capacity (TLC), volume of air in the lungs after maximal inspiration. Dynamic measurements characterize the movement of air into and out of the lungs and show changes in lung mechanics. They include measurement of forced expiratory volume in 1 second, maximum volume of air that can be expired in 1 second from total lung capacity; maximal voluntary ventilation, volume of air that can be expired in 1 minute with the patient’s maximum voluntary effort; and forced vital capacity, maximal volume of air that the patient can exhale from TLC. (Peak flow rate, which can be obtained at the bedside, is also a dynamic measurement of pulmonary function.)

❑ Exercise stress test evaluates the ability to transport O₂ and remove CO₂with increasing metabolic demands.

❑ Polysomnography can diagnose sleep disorders.

❑ Lung scan (ventilation-perfusion or scintiphotography scan) demonstrates ventilation and perfusion patterns. It’s used primarily to evaluate pulmonary embolus.

❑ Arterial blood gas (ABG) analysis assesses gas exchange. Decreased PaO₂ may indicate hypoventilation, ventilation-perfusion mismatch, or shunting of blood away from gas exchange sites. Increased partial pressure of arterial carbon dioxide (PaCO₂) reflects marked ventilation-perfusion mismatch or hypoventilation; decreased PaCO₂ reflects increased alveolar ventilation. Changes in pH may reflect metabolic or respiratory dysfunction.

❑ Pulse oximetry is a noninvasive assessment of arterial oxygen saturation.

❑ Capnography may be used either transcutaneously or in ventilator circuit to determine PaCO₂ trends.

Invasive tests include:

❑ Bronchoscopy permits direct visualization of the trachea and mainstem, lobar, segmental, and subsegmental bronchi. It may be used to localize the site of lung hemorrhage, visualize masses in these airways, and collect respiratory tract secretions. Brush biopsy may be used to obtain specimens from the lungs for microbiological stains, culture, and cytology. Lesion biopsies may be performed by using small forceps under direct visualization (when present in the proximal airways) or with the aid of fluoroscopy (when present distal to regions of direct visualization). Bronchoscopy can also be used to clear secretions and remove foreign bodies.

❑ Thoracentesis permits removal of pleural fluid for analysis.

❑ Pleural biopsy obtains pleural tissue for histologic examination and culture.

❑ Pulmonary artery angiography, the injection of dye into the pulmonary artery, can locate pulmonary embolism. This is considered the gold standard for diagnosing pulmonary emboli.

❑ Positron emission tomography scan uses a short-life radionuclide. Increased uptake of the substance is seen in malignant cells.

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Source: Professional Guide to Diseases (Eighth Edition), 2005

Severe acute respiratory syndrome: Diagnosis
(Professional Guide to Diseases (Eighth Edition))

Diagnosis of severe respiratory illness is made when the patient has a fever greater than 100.4° F (38° C) or upon clinical findings of lower respiratory illness and a chest X-ray demonstrating pneumonia or acute respiratory distress syndrome.

Laboratory validation for the virus includes cell culture of SARS-CoV, detection of SARS-CoV ribonucleic acid by the reverse transcription polymerase chain reaction (PCR) test, or detection of serum antibodies to SARS-CoV. Detectable levels of antibodies may not be present until 21 days after the onset of illness, but some individuals develop antibodies within 14 days. A negative PCR, antibody test, or cell culture doesn’t rule out the diagnosis.

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Source: Professional Guide to Diseases (Eighth Edition), 2005

Cough, barking: History and physical examination
(Professional Guide to Signs & Symptoms (Fifth Edition))

Ask the child’s parents when the barking cough began and what other signs and symptoms accompanied it. When did the child first appear to be ill? Has he had previous episodes of croup syndrome? Did his condition improve upon exposure to cold air?

Spasmodic croup and epiglottiditis typically occur in the middle of the night. The child with spasmodic croup has no fever, but the child with epiglottiditis has a high fever of sudden onset. An upper respiratory tract infection typically is followed by laryngotracheobronchitis.

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Source: Professional Guide to Signs & Symptoms (Fifth Edition), 2006

Cough, nonproductive: History and physical examination
(Professional Guide to Signs & Symptoms (Fifth Edition))

Ask the patient when his cough began and whether any body position, time of day, or specific activity affects it. How does the cough sound—harsh, brassy, dry, or hacking? Try to determine if the cough is related to smoking or a chemical irritant. If the patient smokes or has smoked, note the number of packs smoked daily multiplied by years (“pack-years”). Next, ask about the frequency and intensity of the coughing. If he has any pain associated with coughing, breathing, or activity, when did it begin and where is it located?

Ask the patient about recent illness (especially a cardiovascular or pulmonary disorder), surgery, or trauma. Also ask about hypersensitivity to drugs, foods, pets, dust, or pollen. Find out which medications the patient takes, if any, and ask about recent changes in schedule or dosages. Also ask about recent changes in his appetite, weight, exercise tolerance, or energy level; recent exposure to irritating fumes, chemicals, or smoke; and recent travel to foreign countries.

As you’re taking his history, observe the patient’s general appearance and manner: Is he agitated, restless, or lethargic; pale, diaphoretic, or flushed; anxious, confused, or nervous? Also, note whether he’s cyanotic or has clubbed fingers or peripheral edema.

Cultural Cue: Because of the fear of being known as someone with tuberculosis (TB), the patient may be reluctant to provide information about his signs and symptoms such as cough. Ask the patient at risk for TB—those born in another country, those in contact with acute TB, and those with high-risk behaviors—about potential TB exposure.

Next, perform a physical examination. Start by taking the patient’s vital signs. Check the depth and rhythm of his respirations, and note wheezing or “crowing” noises that occur with breathing. Feel the patient’s skin: Is it cold or warm; clammy or dry? Check his nose and mouth for congestion, inflammation, drainage, or signs of infection. Inspect his neck for distended veins and tracheal deviation, and palpate for masses or enlarged lymph nodes.

Examine his chest, observing its configuration and looking for abnormal chest wall motion. Do you note any retractions or use of accessory muscles? Percuss for dullness, tympany, or flatness. Auscultate for wheezing, crackles, rhonchi, pleural friction rub, and decreased or absent breath sounds. Finally, examine his abdomen for distention, tenderness, or masses, and auscultate it for abnormal bowel sounds.

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Source: Professional Guide to Signs & Symptoms (Fifth Edition), 2006

Cough, productive: History and physical examination
(Professional Guide to Signs & Symptoms (Fifth Edition))

When the patient’s condition permits, ask when the cough began and how much sputum he’s coughing up each day. (The normal tracheobronchial tree can produce up to 3 oz [89 ml] of sputum per day.) At what time of day does he cough up the most sputum? Is his sputum production affected by what or when he eats, his activities, or his environment? Ask him if he has noticed an increase in sputum production since his coughing began. This may result from external stimuli or from such internal causes as chronic bronchial infection or a lung abscess. Also ask about the color, odor, and consistency of the sputum. Blood-tinged or rust-colored sputum may result from trauma due to coughing or from an underlying condition, such as a pulmonary infection or a tumor. Foul-smelling sputum may result from an anaerobic infection, such as bronchitis or a lung abscess.

How does the cough sound? A hacking cough results from laryngeal involvement, whereas a “brassy” cough indicates major airway involvement. Does the patient feel any pain associated with his productive cough? If so, ask about its location and severity and whether it radiates to other areas. Does coughing, changing body position, or inspiration increase or help relieve his pain?

Examine the patient’s mouth and nose for congestion, drainage, or inflammation. Note his breath odor: Halitosis can be a sign of pulmonary infection. Inspect his neck for distended veins, and palpate it for tenderness, masses, and enlarged lymph nodes. Observe his chest for accessory muscle use, retractions, and uneven chest expansion, and percuss it for dullness, tympany, or flatness. Finally, auscultate for pleural friction rub and abnormal breath sounds, including rhonchi, crackles, or wheezing. (See Productive cough: Causes and associated findings, pages 206 and 207.)

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Source: Professional Guide to Signs & Symptoms (Fifth Edition), 2006

Fever [Pyrexia]: History and physical examination
(Professional Guide to Signs & Symptoms (Fifth Edition))

If the patient’s fever is only mild to moderate, ask him when it began and how high his temperature reached. Did the fever disappear, only to reappear later? Did he experience any other symptoms, such as chills, fatigue, or pain?

Obtain a complete medical history, noting especially immunosuppressive treatments or disorders, infection, trauma, surgery, diagnostic testing, and use of anesthesia or other medications. Ask about recent travel because certain diseases are endemic.

Let the history findings direct your physical examination. (See Differential diagnosis: Fever, pages 338 and 339.) Because fever can accompany diverse disorders, the examination may range from a brief evaluation of one body system to a comprehensive review of all systems. (See How fever develops, page 340.)

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Source: Professional Guide to Signs & Symptoms (Fifth Edition), 2006

Cough: History
(The 10-Minute Diagnosis Manual: Symptoms and Signs in the Time-Limited Encounter)

A. Characteristics of the cough. What is the type of cough (barking, brassy, wheezy, nocturnal, paroxysmal)? What are the duration, timing, and triggers? Are there associated symptoms of fever, sputum production, dypsnea, hemoptysis, and weight loss? Are there clear relieving factors? Ask specifically about postnasal drip as patients often do not volunteer this information. A good history is the key to diagnosis.

1. Upper respiratory causes most commonly relate to postnasal drip. In adults, sinusitis, pharyngitis, and allergic rhinitis should be considered. In children, concomitant otitis media should be excluded.

2. Lower respiratory causes include lung (bronchitis, asthma, pneumonia, bronchiectasis, and in children, foreign body aspiration) and cardiac [congestive heart failure (CHF) and mitral stenosis].

3. Nonrespiratory causes include GERD, drug effects [e.g., angiotensin converting enzyme (ACE)-inhibitors], and psychogenic.

B. Smoking patients should be identified early as bronchitis and lung cancer are possibilities. Passive smoking is also a risk factor, especially in children. Office visits for cough represent teachable moments for smoking cessation education. Smoking cessation has been shown to reduce respiratory symptoms by 50%.

C. Psychosocial impact of the cough reflects severity and the need for further workup. Has the patient missed school or work? Is the sleeping partner disturbed? Is there avoidance of exercise because it triggers cough? In chronic, episodic cough, a correct diagnosis of asthma can considerably improve quality of life. A psychogenic cause for cough and behavioral problems in children may be unmasked here.

D. Other information. Associated chest pain should direct the history toward pleurisy or rib fracture secondary to chronic cough. Occupational exposures (toxic fumes, chemicals, birds and animals), systemic diseases [rheumatoid arthritis, breast and prostate cancer metastases, human immunodeficiency virus disease (HIV)] and drug exposure (ACE-inhibitors, cyclophosphamide, and methotrexate) are important factors to consider in the cause. Cough with significant weight loss should trigger a workup for TB, HIV, or lung cancer in the smoker.

Physical examination

A. Focused physical examination (PE) should include vital signs (temperature, pulse, respiratory rate, and blood pressure), ear, nose, sinuses, throat (ENST), and a full lung examination with the chest uncovered. Normal lung examination often excludes pneumonia but not asthma, bronchitis, COPD, GERD, or lung cancer. It is more effective to examine the lung before the ENST in young children because the ENST examination is more traumatic and can induce crying. In the older patient, especially the postmenopausal woman, rib palpation may be included to isolate fracture secondary to osteoporosis.

B. Additional PE. The cardiovascular examination is directed at a diagnosis of CHF. Associated lymphadenopathy suggests infection or neoplasm. Wasting can be ominous (cancer or HIV). Abdominal examination may reveal a tender enlarged liver in CHF, or epigastric tenderness in GERD (Chapters 7.5 and 9.6).

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Source: The 10-Minute Diagnosis Manual: Symptoms and Signs in the Time-Limited Encounter, 2000

Fever: History
(The 10-Minute Diagnosis Manual: Symptoms and Signs in the Time-Limited Encounter)

A. Taking a detailed patient history is critical; include questions relating to travel, animal exposure, occupation, injuries or operations, household members or contacts who are ill, medications, past illnesses, and a complete review of systems.

B. Chills, malaise, myalgia, headache, and fever are common with infectious diseases.

C. The febrile pattern may be helpful in making a diagnosis. Antipyretics, antibiotics, and glucocorticoids affect the fever pattern. Specific patterns of fever are shown in Table 2.4.

Physical examination

A. The examination should include the skin, lymph nodes, eyes, nail beds, heart, lungs, abdomen, joints, nervous system, and genitourinary system, including rectal and bimanual pelvic examinations.

B. Infections will increase the pulse rate approximately 10 beats per minute for each 0.5°C (1.0°F) temperature increase.

C. When fever is present, the respiratory rate will frequently increase above the usual 12 to 14 breaths per minute.

D. Infections with Mycoplasma pneumonia, psittacosis, and typhoid fever are often associated with a relative bradycardia.

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Source: The 10-Minute Diagnosis Manual: Symptoms and Signs in the Time-Limited Encounter, 2000

Rash Accompanied by Fever: History
(The 10-Minute Diagnosis Manual: Symptoms and Signs in the Time-Limited Encounter)

History is quite important and should include standard items, such as onset, duration, aggravating factors, relieving factors, and associated symptoms. Additionally, other factors to consider, include:

A. Exposure history. Are any other family members or close contacts ill? Is there a history of exposure to brackish water, mosquitoes, foreign travel, and so forth?

B. Are there any underlying illnesses or a significant possibility of immunologic compromise (e.g., undiagnosed HIV infection)?

Physical examination

A. Examine the lesions and their distribution carefully. Classify the rash as petechial, maculopapular, vesiculobullous, erythematous, or urticarial. Note the distribution of the rash. For instance, rubella and rubeola generally begin on the face and spread to the trunk, whereas RMSF petechiae tend to occur on the ankles and wrists first.

B. Conduct a general physical examination. Areas of particular concern are:

1. Head, eyes, ears, nose, and throat. The presence of Koplik’s spots is pathognomic for rubeola. The discovery of a tick lends support to the diagnosis of RMSF. Sinusitis may represent a source for meningococcemia. Pharyngitis in a young adult with diffuse erythema may be caused by C. haemolyticum. Mucous membrane swelling may indicate early anaphylaxis.

2. Lung examination. Expiratory wheezing, especially in a patient who has recently received medications or contrast dye, can indicate anaphylaxis. Evidence of pneumonia is consistent with psittacosis and mycoplasma.

3. Cardiac examination. Cardiovascular collapse is associated with meningococcemia and other sepsis. A new murmur (Chapters 7.6 and 7.7) may indicate subacute bacterial endocarditis in a patient with subungual or scleral petechiae.

4. Genital examination. Purulent urethral drainage or evidence of pelvic inflammatory disease supports consideration of gonorrhea. A chancre would support a diagnosis of syphilis, although palmar lesions often occur well after healing of the initial chancre.

5. Joint examination and extremities. A petechial rash near the ankles and wrists is suggestive of RMSF. Evidence of joint swelling supports a diagnosis of meningococcemia or gonococcemia. A maculopapular rash may be seen in juvenile rheumatoid arthritis and other rheumatologic conditions as well.

6. Neurologic examination. Evidence of meningitis supports a diagnosis of meningococcemia. Patients with RMSF may also have meningeal signs.

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Source: The 10-Minute Diagnosis Manual: Symptoms and Signs in the Time-Limited Encounter, 2000

Fever of Unknown Origin: Differential Overview
(Field Guide to Bedside Diagnosis)

Infection

❑ HIV

❑ Tuberculosis

❑ Endocarditis

❑ Osteomyelitis

❑ Malaria

❑ Syphilis

❑ Zoonosis

❑ Typhoid fever

❑ Chronic meningococcemia

Neoplasm

❑ Lymphoma

❑ Liver metastases

❑ Renal cell carcinoma

❑ Atrial myxoma

Collagen-Vascular Disease

❑ Giant cell arteritis

❑ Systemic lupus erythematosus

❑ Vasculitis

❑ Rheumatic fever

❑ Still disease

Other

❑ Drugs

❑ Heat stroke

❑ Factitious

❑ Malignant hyperthermia

❑ Multiple pulmonary emboli

Diagnostic Approach

Fever of unknown origin (FUO), when a fever over 101°F (38.5°C) remains unexplained for longer than 3 weeks, is usually a result of infection (40%), neoplasm (20%), or collagen-vascular disease (20%). It is most commonly caused by an atypical presentation of a common disease. Always document the fever before pursuing the evaluation.

Consider relatively hidden (deep) sites: retroperitoneum (hematoma or infection), bone, dental, sinus, ovary, prostate, subphrenic (following abdominal surgery), renal, spleen, or prostheses. With FUO in a hospitalized patient, consider sequestered sites (e.g., sinuses in intubated patients or implanted hardware), indwelling lines, C. difficile, or drug reactions. With FUO in a neutropenic patient, consider catheters, perianal infections, Candida, and Aspergillus. Cardinal signs may be absent, e.g., meningitis with opportunistic pathogens without meningismus in 63%, and pneumonia without purulent sputum in 92%. Neutropenic fevers are usually due to bacteremia, with fungal organisms becoming predominant after 7 days of unremitting fever. Fever may also be due to the underlying neoplasm, drugs such as antibiotics, or blood products.

Examine for subtle clues:

• Petechial eruptions in meningococcemia and Rocky Mountain Spotted Fever

• Pustular lesions in gonococcemia or staphylococcal sepsis

• Ecthyma gangrenosum in Pseudomonas sepsis

• Splinter hemorrhages, conjunctival hemorrhages, Roth spots, Osler nodes, and Janeway lesions in endocarditis

• Choroidal tubercles in miliary tuberculosis and candidemia

• Splenomegaly in endocarditis, lymphoma, and cirrhosis

• Hepatic bruit or friction rub in subphrenic abscess

• Temporal artery or scalp tenderness or jaw claudication in giant cell arteritis

• Epitrochlear lymphadenopathy in syphilis

Extreme elevations of fever (.40°C) are found in heat stroke, hypothalamic dysfunction, meningitis, midbrain hemorrhage, falciparum malaria, Rocky Mountain Spotted Fever, typhus, sepsis, malignant hyperthermia, and hypernephroma.

Relative bradycardia occurs in salmonellosis (typhoid fever), meningitis with increased intracranial pressure, mycoplasma and legionella pneumonia, factitious fever, tularemia, brucellosis, mumps, hepatitis, and with concomitant beta blockers. Bradycardia in fever may also signal cardiac conduction abnormalities in acute rheumatic fever, Lyme disease, viral myocarditis, or endocarditis with valve ring abscess.

Relapsing fevers (days of fever alternating with days without) occur in brucellosis (fever with physical activity), Hodgkin disease, extrapulmonary tuberculosis, malaria, and Lyme disease. Hectic fever (difference between peak and trough .1.5°C) suggests abscess, pyelonephritis, ascending cholangitis, tuberculosis, lymphoma, and drug reactions. Absence of diurnal variation suggests a central source. Reversal of the diurnal pattern (“typhus inversus”) occurs with disseminated tuberculosis, typhoid fever, polyarteritis nodosa, and salicylate toxicity.

FUO in patients from the developing world include tuberculosis, typhoid, amebic liver abscesses, AIDS, and geographically restricted infections such as malaria, schistosomiasis, brucellosis, kala azar, filariasis, or Lassa fever. They may present after long incubation or latency periods.

When FUO lasts longer than 6 months, consider factitious fever, granulomatous hepatitis, neoplasm, Still disease, infection, collagen-vascular disease, or exaggerated circadian rhythm.

Patients who remain undiagnosed have a good prognosis (83% resolution in 1 year, 4% mortality).

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Source: Field Guide to Bedside Diagnosis, 2007

Acute Cough: Differential Overview
(Field Guide to Bedside Diagnosis)

❑ Viral upper respiratory infection

❑ Asthma

❑ Sinusitis

❑ Mycoplasma bronchitis

❑ Pneumonia

❑ Gastroesophageal reflux

❑ Congestive heart failure

❑ ACE inhibitor

❑ Aspiration

❑ Cough in HIV

❑ Thermal

❑ Fume inhalation

❑ Pertussis

❑ Lung abscess

Diagnostic Approach

The main issue in diagnosis is differentiating respiratory viruses, which cause most cases, from bacterial infection such as pneumonia, which would benefit from treatment with antibiotics, and from influenza, for which antivirals are effective. The classic presentation of bacterial pneumonia is acute onset with a progressive course marked by cough productive of yellow or green sputum, fever to 100˚ to 104˚F with chills or rigors, and pleuritic chest pain. The patient often appears “toxic.” The affected lung will often have coarse rales and bronchial breath sounds, and there may be localized percussive dullness. Viral pneumonia is associated with upper respiratory signs such as nasal congestion and sore throat, and by a nonproductive cough. Use of the Pneumonia diagnosis rule is helpful: Temperature .37.8˚C (100˚F); pulse .100; rales; decreased breath sounds; and no asthma each score 1.

Detection of induced bronchial hyperreactivity (reactive airways disease), which benefits from bronchodilator or corticosteroid treatment, is also important. Wheezing, shortness of breath, and a predisposition (atopy or smoker) are helpful clinical clues.

A cough appearing mostly at night suggests congestive heart failure or reflux. Confusion and absence of fever are common presenting findings in older adults.

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Source: Field Guide to Bedside Diagnosis, 2007

Chronic Cough: Differential Overview
(Field Guide to Bedside Diagnosis)

❑ Upper respiratory infection

❑ Allergy

❑ Asthma

❑ Chronic bronchitis

❑ Chronic sinusitis

❑ Gastroesophageal reflux

❑ ACE inhibitor

❑ Pollutants

❑ Psychogenic

❑ Foreign body

❑ Congestive heart failure

❑ Lung cancer

❑ Tuberculosis

❑ Mediastinal mass

❑ Bronchiectasis

❑ Pulmonary fibrosis

❑ Cystic fibrosis

❑ Aspergillosis

Diagnostic Approach

Chronic cough persists 3 weeks or longer. During vigorous coughing intrathoracic pressure of 300 mm Hg and expiratory velocity of 500 miles per hour develop, which over time are responsible for the secondary effects of exhaustion, insomnia, chest wall pain, dizziness, syncope, and urinary incontinence. Postnasal drip, asthma, and gastroesophageal reflux are responsible for 99.4% of cases in patients with the characteristics: nonsmoker, no use of ACE inhibitor, and normal or stable chest x-ray.

Green color in the sputum may be caused by either polymorphonuclear leukocytes or eosinophils. Hoarseness suggests tumor with involvement of the vocal cords or recurrent laryngeal nerve, or it may suggest chronic esophageal reflux.

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Source: Field Guide to Bedside Diagnosis, 2007

Respiratory syncytial virus infection: Diagnosis
(Handbook of Diseases)

The following clinical findings and epidemiologic information aid in the diagnosis:

❑ Cultures of nasal and pharyngeal secretions may show RSV.

❑ Serum antibody titers may be elevated, but before age 6 months, maternal antibodies may impair test results.

❑ Serology for RSV is positive.

❑ Chest X-rays help detect pneumonia or bronchiolitis.

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Source: Handbook of Diseases, 2003

Acute respiratory failure in COPD: Diagnosis
(Handbook of Diseases)

Progressive deterioration in ABG levels and pH, when compared with the patient’s baseline values, strongly suggests ARF in COPD patients. (In patients with essentially normal lung tissue, a pH less than 7.35 usually indicates ARF, but COPD patients display an even greater deviation from this normal value, as they do with blood Paco₂ and Pao₂.) The following findings further support the diagnosis:

Bicarbonate levels are increased, indicating metabolic alkalosis or metabolic compensation for chronic respiratory acidosis.

Hb levels and hematocrit are abnormally low, which may be due to blood loss, indicating decreased oxygen-carrying capacity.

Serum electrolyte levels may indicate hypokalemia, which may result from compensatory hyperventilation — an attempt to correct alkalosis; hypochloremia is common with metabolic alkalosis.

White blood cell count is elevated if ARF is due to bacterial infection; in certain cases of profound septicemia, the leukocyte count may be decreased. Gram stain and sputum culture can identify pathogens.

Chest X-rays reveal pulmonary pathology, such as emphysema, atelectasis, lesions, pneumothorax, infiltrates, or effusions.

Electrocardiogram reveals arrhythmias, which commonly suggest cor pulmonale and myocardial hypoxia. Large P waves (“p pulmonale”) may indicate a history of right-sided heart failure.

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Source: Handbook of Diseases, 2003

Rheumatic fever and rheumatic heart disease: Diagnosis
(Handbook of Diseases)

Recognition of one or more classic signs or symptoms (carditis, polyarthritis, chorea, erythema marginatum, or subcutaneous nodules) and a detailed patient history allow diagnosis. The following laboratory data support the diagnosis:

❑ White blood cell count and erythrocyte sedimentation rate may be elevated (during the acute phase); blood studies show slight anemia from suppressed erythropoiesis during inflammation.

❑ C-reactive protein is positive (especially during the acute phase).

❑ Cardiac enzyme levels may be increased in those with severe carditis.

❑ Antistreptolysin O titer is elevated in 95% of patients within 2 months of onset. (Rising antiDNase B test results can also detect recurrent streptococcal infection.)

❑ Electrocardiography changes aren’t diagnostic, but the PR interval is prolonged in 20% of patients.

❑ Chest X-rays show normal heart size (except with myocarditis, heart failure, or pericardial effusion).

❑ Echocardiography helps evaluate valvular damage, chamber size, and ventricular function.

❑ Cardiac catheterization evaluates valvular damage and left ventricular function in those with severe cardiac dysfunction.

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Source: Handbook of Diseases, 2003

Respiratory alkalosis: Diagnosis
(Handbook of Diseases)

Arterial blood gas (ABG) analysis confirms respiratory alkalosis and rules out respiratory compensation for metabolic acidosis. Findings include a Paco₂ below 35 mm Hg, a pH that’s elevated in proportion to the fall in Paco₂ in the acute stage but that drops toward normal in the chronic stage, and a bicarbonate level that’s normal in the acute stage but below normal in the chronic stage.

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Source: Handbook of Diseases, 2003

Respiratory distress syndrome: Diagnosis
(Handbook of Diseases)

Although signs of respiratory distress in a premature neonate during the first few hours of life strongly suggest respiratory distress syndrome, the following tests are necessary to confirm the diagnosis:

❑ Chest X-ray may be normal for the first 6 to 12 hours (in 50% of neonates with respiratory distress syndrome) but later shows a fine reticulonodular pattern.

❑ Arterial blood gas (ABG) analysis shows decreased partial pressure of arterial oxygen (Pao₂); normal, decreased, or increased partial pressure of arterial carbon dioxide; and decreased pH (from respiratory or metabolic acidosis or both).

❑ Pulmonary function studies may be necessary.

When a cesarean section is necessary before the 36th week of gestation, amniocentesis allows determination of the lecithin-sphingomyelin ratio, which helps to assess prenatal lung development and the risk of respiratory distress syndrome.

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Source: Handbook of Diseases, 2003

Respiratory acidosis: Diagnosis
(Handbook of Diseases)

❑ The following arterial blood gas (ABG) levels confirm respiratory acidosis: a Paco₂ exceeding the normal level of 45 mm Hg, pH usually below the normal range of 7.35 to 7.45, and a bicarbonate level that’s normal in the acute stage but elevated in the chronic stage.

❑ Chest X-ray, computed tomography scan, or pulmonary function test may help diagnose lung disease.

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Source: Handbook of Diseases, 2003

Fever: History
(Alarming Signs and Symptoms: Lippincott Manual of Nursing Practice Series)

If the patient’s fever is mild to moderate, ask him when it began and how high his temperature reached. Did the fever disappear, only to reappear later? Did he experience any other symptoms, such as chills, fatigue, or pain?

Obtain a complete medical history, noting immunosuppressive treatments or disorders, infection, trauma, surgery, diagnostic testing, and use of anesthesia or other medications. Ask about recent travel because certain diseases are endemic.

Physical examination

Let the history findings direct your physical examination. Because fever can accompany diverse disorders, the examination may range from a brief evaluation of one body system to a comprehensive review of all systems. (See How fever develops, pages 148.) Assess vital signs and evaluate the patient for complications related to the fever such as dehydration, body aches, fatigue, anorexia, and seizure activity.

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Source: Alarming Signs and Symptoms: Lippincott Manual of Nursing Practice Series, 2007

Cough, barking: History
(Alarming Signs and Symptoms: Lippincott Manual of Nursing Practice Series)

Determine when the barking cough began and other associated signs and symptoms. Determine when the child first appeared to be ill and ask if there have been previous episodes of croup syndrome.

Physical examination

Assess the respiratory system, noting rate and pattern of respirations. Assess the patient for signs of hypoxia. Stay alert for signs of airway obstruction (nasal flaring, sternal retraction, stridor).

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Source: Alarming Signs and Symptoms: Lippincott Manual of Nursing Practice Series, 2007

Cough, productive: History
(Alarming Signs and Symptoms: Lippincott Manual of Nursing Practice Series)

Determine the onset of the cough and amount of daily sputum production. (The normal tracheobronchial tree can produce up to 3 oz [89 ml] of sputum per day.) Determine the time of day that the most sputum is produced and relationship of food to sputum production. Also ask about the color, odor, and consistency of the sputum. Blood-tinged or rust-colored sputum may result from trauma due to coughing or from an underlying condition, such as a pulmonary infection or tumor. Foul-smelling sputum may result from an anaerobic infection, such as bronchitis or lung abscess.

Determine cough characteristics. A hacking cough results from laryngeal involvement, whereas a “brassy” cough indicates major airway involvement. Ask the patient about cigarette, drug, and alcohol use and if there has been weight or appetite changes. Find out if he has a history of asthma, allergies, or respiratory disorders, and ask about recent illnesses, surgery, or trauma. Determine a medication history, including over-the-counter medications. Ask the patient if his work involves chemicals or respiratory irritants.

Physical examination

Examine the patient’s mouth and nose for congestion, drainage, or inflammation. Note breath odor: Halitosis can be a sign of pulmonary infection. Inspect his neck for jugular vein distention, and palpate for tenderness and masses or enlarged lymph nodes. Observe his chest for accessory muscle use, retractions, and uneven chest expansion, and percuss for dullness, tympany, or flatness. Finally, auscultate for pleural friction rub and abnormal breath sounds — rhonchi, crackles, or wheezes.

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Source: Alarming Signs and Symptoms: Lippincott Manual of Nursing Practice Series, 2007

Fever: History
(Signs & Symptoms: A 2-in-1 Reference for Nurses)

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Source: Signs & Symptoms: A 2-in-1 Reference for Nurses, 2007

Cough, barking: History
(Signs & Symptoms: A 2-in-1 Reference for Nurses)

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Source: Signs & Symptoms: A 2-in-1 Reference for Nurses, 2007

Cough, nonproductive: History
(Signs & Symptoms: A 2-in-1 Reference for Nurses)

Ask the patient when his cough began and whether body position, time of day, or specific activity affects it. How does the cough sound — harsh, brassy, dry, or hacking? Try to determine if the cough is related to smoking or a chemical irritant. If the patient smokes or has smoked, note the number of packs smoked daily multiplied by years (“pack years”). Next, ask about the frequency and intensity of the coughing. If he has pain associated with coughing, breathing, or activity, when did it begin? Where is it located?

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Source: Signs & Symptoms: A 2-in-1 Reference for Nurses, 2007

Cough, productive: History
(Signs & Symptoms: A 2-in-1 Reference for Nurses)

When the patient’s condition permits, ask when the cough began, and find out how much sputum he’s coughing up each day. (The normal tracheobronchial tree can produce up to 3 oz [88.7 ml] of sputum per day.) At what time of day does he cough up the most sputum? Does his sputum production have any relationship to what or when he eats, or to his activities or environment? Ask him if he has noticed an increase in sputum production since his coughing began. This may result from external stimuli or from such internal causes as chronic bronchial infection or a lung abscess. Also ask about the color, odor, and consistency of the sputum. Blood-tinged or rust-colored sputum may result from trauma due to coughing or from an underlying condition, such as a pulmonary infection or a tumor. Foul-smelling sputum may result from an anaerobic infection, such as bronchitis or lung abscess.

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Source: Signs & Symptoms: A 2-in-1 Reference for Nurses, 2007

Cough: Clinical Features and Diagnosis
(The Diagnostic Approach to Symptoms and Signs in Pediatrics)

Infection/Inflammation

Upper Respiratory Tract Infection

URI (commoncold) is acute viral infection.

Common pathogens include rhinoviruses,parainfluenza viruses, respiratory syncytial virus (RSV), and coronaviruses.Other viruses that occasionally cause common cold are adenoviruses,enteroviruses, influenza viruses, and reoviruses.

Usual clinical findings are watery,mucoid, or purulent discharge; dry, hacking cough; and inflamednasal mucosa.

Diagnosis is clinical.

Sinusitis

Usuallypresents with history of purulent nasal discharge and persistentcough of >10 days' duration. Less common presentationis combination of fever, headache, and facial pain or sinus tenderness.

Usually clinical diagnosis.

CT should be performed when orbitalabscess or intracranial complication is suspected.

Laryngitis

Most frequentcause is viral URI.

Hoarseness and dry, hacking cough,which may last up to 1 wk, are usual clinical findings.

Usually clinical diagnosis.

Croup

Characterizedby a barking cough and stridor ± fever.

See Chap.63, Stertor, Stridor, and Airway Obstruction.

Tracheitis

Often crouplikeillness with cough and stridor precedes sudden onset of respiratory distressand high fever.

Clinical picture suggests bacterialtracheitis.

See Chap.63, Stertor, Stridor, and Airway Obstruction.

Bronchitis

Inflammatoryprocess affecting trachea and bronchi. Most episodes are causedby viruses (e.g., RSV, parainfluenza viruses, influenza viruses,rhinoviruses, and adenoviruses).

Hacking cough appears several daysafter onset of typical URI. Rhonchi may be heard, but crackles areinfrequent. Presence of wheezing usually indicates presence of reactiveairways disease.

Usually clinical diagnosis.

Pertussis

B. pertussisinfection begins with nasal discharge, which is followed by paroxysmal coughthat often has staccato quality. Whoop may follow paroxysm.

Fever may or may not occur.

There is usually leukocytosis withpredominance of lymphocytes.

Apnea is serious complication, especiallyin young infants.

Duration of illness may be as longas 6–10 wks.

Chest radiograph may be normal or showperihilar infiltrates.

Positive direct immunofluorescent assayof nasopharyngeal secretions suggests diagnosis, but false-positiveand false-negative results occur.

Positive nasopharyngeal culture confirmsdiagnosis.

Bronchiolitis

Usuallycaused by RSV and occasionally by parainfluenza viruses, influenzaviruses, and adenoviruses.

Occurs during winter months, oftenin epidemics.

Rhinorrhea usually precedes cough,which may be persistent and harsh. Expiratory wheezing is prominentfinding.

See Chap.75, Wheezing.

Pneumonia

Definedas inflammation of lung parenchyma that may be caused by infection.

Frequently presents with fever, cough,and respiratory distress. Crackles and wheezes may be heard on exam.Decreased breath sounds and dullness to percussion indicate areaof lung consolidation.

Presence of pneumonia usually can beconfirmed by chest radiography, although early in illness radiographcan appear normal.

Specific cause requires further investigation.

Viral

Accountsfor most cases of pneumonia in infancy and childhood.

Most common viruses causing pneumoniainclude RSV, parainfluenza viruses, adenoviruses, and influenzaviruses. Less common causes are rhinoviruses and coronaviruses.

Cytomegalovirus and herpes simplexvirus may cause pneumonia in newborn or in immunocompromised individuals.

May also be caused by measles, varicella,and Hantavirus infection.

Chest radiograph frequently shows involvementof both lungs, with peribronchial thickening, perihilar linear densities,and patchy infiltrates. Segmental or lobar consolidation, hilaradenopathy, and pleural effusions are unusual.

Nasal wash cultures or polymerase chainreaction (PCR) of nasal secretions may sometimes diagnose specificviral infection.

RSV antigen may be detected by enzymeimmunoassay or immunofluorescent techniques.

Bacterial

Pathogenscausing bacterial pneumonia vary with age of child.

Most common causes of bacterial pneumoniain neonates are group B Streptococcus and gram-negative entericbacteria (E. coli, K. pneumoniae, P. aeruginosa).

In infancy, childhood, and adolescence,S. pneumoniae is most common, whereas S. aureus and group A Streptococcusare much less common.

H. influenzae type b has become unusualcause of pneumonia, since advent of H. influenzae vaccine.

M. tuberculosis can cause infectionat any age.

Clinical findings with bacterial pneumoniausually include fever, cough that may be productive of sputum inolder child, and some degree of respiratory distress.

Leukocytosis with predominance of polymorphonuclearleukocytes is common finding.

Pleural effusions and pneumatocelesare more frequent with bacterial pneumonia than with viral pneumonia.

Chest radiograph usually shows segmentalor lobar infiltrate.

Diagnosis of bacterial pneumonia canbe confirmed by positive blood, pleural fluid, or lung biopsy cultures.McCarthy et al. (1999) demonstrated that PCR may be used to diagnosepneumonia caused by S. pneumoniae using sample of pleural fluid.

Pharyngeal or sputum culture that haslarge numbers of single organism is suggestive but not diagnostic.

Counterimmune electrophoresis and latexagglutination tests have successfully detected bacterial antigensof S. pneumoniae, group B Streptococcus, and H. influenzae typeb in urine, so these tests may be diagnostic.

Tuberculosis

Usual modeof transmission of M. tuberculosis infection is by inhalation.

Positive skin test with PPD may beobserved 2–12 wks after exposure.

Children with disease usually haveprimary pulmonary TB with cough and fever.

In most cases of TB infection, individualis asymptomatic, primary complex of infection is not seen on chestradiograph, and disease does not progress.

In TB disease, individual has clinicalor radiographic findings and disease may be pulmonary or nonpulmonary.

Chest radiograph shows involvementof segment or lobe, usually with enlarged regional lymph nodes.With progression, cavitary lesions or miliary disease can occur.

Acid-fast bacilli smears and culturesshould be performed in anyone with suspected TB. In young child,especially if cough is nonproductive, best culture material is fromearly morning gastric aspirate. Otherwise, isolation of tuberclebacilli by culture of sputum, urine, pleural fluid, cerebrospinalfluid, other body fluids, or biopsy material confirms diagnosis.

Negative PPD never excludes infectionor disease with TB. Anergy may be due to young age, viral infections,immunosuppression, and severe disseminated TB.

Chlamydia

Pneumoniadue to C. trachomatis usually occurs in infants 1–3 mosof age.

Clinical findings include conjunctivitisor history of conjunctivitis, staccato cough, tachypnea, crackles,and mild peripheral eosinophilia. Fever is variable finding.

Chest radiograph usually shows hyperinflationand bilateral interstitial infiltrates.

Positive nasopharyngeal or eye cultureconfirms diagnosis.

Legionella

Legionnaire'sdisease is transmitted by inhalation of aerosolized water contaminated withLegionella species.

Most common cause of Legionella infectionin U.S. is L. pneumophila serogroup 1.

Frequent findings include fever, nonproductivecough, headache, and myalgia.

Chest radiograph usually shows infiltrate.Pulmonary nodules ± cavitation also may occur.

Diagnosis can be confirmed in a numberof ways:

positiveculture of sputum or lung tissue

detection of organisms on smears ofrespiratory tract secretions by direct immunofluorescent assay usingmonoclonal or polyclonal antibodies

DNA probes

serologic testing using indirect immunofluorescenceantibody assay

Increase in antibody titer to ≥1:128is also considered diagnostic.

Nocardia

Nocardiaspecies are funguslike bacteria that live in soil.

Lung is probable portal of entry aswell as most frequent site of infection.

Most common agent in U.S. is N. asteroides.

Clinical findings include fever, cough,chest pain, night sweats, malaise, and weight loss.

Chest radiography shows scattered infiltrates.

Stained smears of sputum, spinal fluid,or pus may reveal gram-positive rods that are variably acid fast.

Positive culture confirms diagnosis.

Mycoplasma

M. pneumoniaeis common cause of pneumonia in school-aged children and adolescents.

Infection with this organism is uncommonin patients <5 yrs of age.

Persistent nonproductive cough andfever are usual presenting features. Other findings include headache,myalgia, sore throat, and macular or papular rash. Crackles andwheezes may be heard on lung exam.

Typically, chest radiograph shows patchy,unilateral, segmental, or subsegmental consolidation, but diffuse,bilateral, interstitial infiltrates may be seen.

Cold agglutinin titer of ≥1:64 issuggestive of diagnosis, although other viral infections (adenoviruses,Epstein-Barr virus) also can produce elevated titer. Complementfixation test is most widely available serologic test, and titerof ≥1:32 during an acute respiratory illness is suggestive ofinfection.

Fungal

Histoplasmosis

Endemicin eastern and midwestern U.S., especially in Mississippi and OhioRiver valleys.

Infection occurs by inhalation of H.capsulatum spores, which are present in soil or dust in barnyardsor other areas that contain bird and bat droppings.

>95% of infectionsare asymptomatic. Common presentation is acute influenza-like illness withpulmonary infiltrates and hilar adenopathy. Disseminated diseasewith fever, cough, pulmonary infiltrates, hepatosplenomegaly, andpancytopenia occurs most frequently in immunocompromised hosts.

Culture of sputum, blood, or bone marrowconfirms diagnosis, as does demonstration of intracellular yeastsin smears of bone marrow or biopsy material from infected tissues.

Detection of H. capsulatum antigenin urine or serum also can be used to diagnose disseminated disease.Single titer of ≥1:32 or 4-fold increase in yeast phase titersis presumptive evidence of active infection. H bands found in immunodiffusionantibody assay also suggest active infection.

Coccidioidomycosis

Endemicin southwestern U.S. Transmission occurs by inhalation of dust-borne sporesof C. immitis.

Primary infection is often asymptomatic,whereas symptomatic infection usually presents with fever and cough.

Chest radiograph may show hilar adenopathyand calcification of healing primary lesion. Granulomatous lesionscan occur in lungs, lymph nodes, bones, joints, skin, and meninges.

Typical clinical and radiologic findingsand positive skin test or ≥1:32 complement fixation antibodytiter are diagnostic. Spherules seen in tracheal aspirates, sputum,urine, or spinal fluid; biopsies of skin lesions or organs; or positivecultures from any of these sources are also diagnostic.

Aspergillosis

Aspergillusspecies grow in soil and in decaying vegetation. Transmission isby inhalation of airborne spores.

Different clinical presentations mayoccur:

Allergicbronchopulmonary aspergillosis with low-grade fever, productivecough, episodic wheezing, transient pulmonary infiltrates, and eosinophilia

Aspergillomas that do not invade lungtissue

Invasive pulmonary disease with feverand productive cough

Disseminated disease with involvementof skin (cutaneous papules and abscesses), heart (endocarditis),bone (osteomyelitis), sinuses (sinusitis), or brain (abscess).

Chest radiograph may show patchy ornodular infiltrates or consolidation ± cavitation.

Branching and septate hyphae in sputumsuggest diagnosis.

Positive sputum or lung biopsy cultureconfirms diagnosis.

Blastomycosis

Infectionwith B. dermatitidis is endemic in southeastern U.S. and in midwestern statesbordering the Great Lakes.

Pulmonary, cutaneous, and disseminatedforms of disease can occur, but pulmonary disease is most commonin children.

Clinical findings of pulmonary diseaseinclude cough, fever, malaise, chest pain, weight loss, and hemoptysis.

Chest radiograph may show infiltrates,cavities, or nodular densities.

Primary cutaneous blastomycosis maypresent with ≥1 subcutaneous nodules that eventually ulcerate.

Disseminated disease produces granulomatouslesions, which may involve liver, spleen, bone, skin, and brain.

Thick-walled single budding yeast formsmay be seen with 10% KOH preparations from sputum, spinalfluid, urine, or skin lesions.

Positive immunodiffusion test on serathat shows precipitin bands (A and B) is evidence for active infection;however, bronchoalveolar lavage or lung biopsy may be necessaryto establish diagnosis in children with pneumonia.

Serologic assays are not reliable fordiagnosis.

Protozoa

P. cariniiinfection occurs almost exclusively in immunocompromised childrenand is common in those affected with HIV.

Clinical findings include nonproductivecough and fever.

Chest radiograph shows bilateral interstitialor air-space disease.

Diagnosis is confirmed by demonstrationof organism in lower respiratory tract secretions or lung tissue.

Induction of sputum in older childrenand adolescents, bronchoscopy with bronchoalveolar lavage, or lungbiopsy can be performed.

Methenamine silver nitrate and toluidineblue O are most useful stains to identify thick-walled cysts.

Chemical Pneumonia

Gasoline,kerosene, and charcoal lighter fluid are hydrocarbons with low surfacetension and viscosity. Because of these properties, aspiration intotracheobronchial tree can easily occur after ingestion.

Acute onset of cough and respiratorydistress and history of ingestion are diagnostic. Within severalhours of ingestion, chest radiograph may show evidence of pneumonia,with infiltrates commonly in right middle and lower lobes.

Aspiration Pneumonia

Interferencewith normal swallowing predisposes to aspiration of oral and gastricsecretions as well as food. Children with gastroesophageal reflux,tracheoesophageal fistula, or neurologic disorders with swallowingdysfunction are more prone to develop aspiration pneumonia.

Onset of respiratory distress afterchoking, gagging, coughing, or vomiting episodes should lead oneto suspect aspiration pneumonia.

Cystic Fibrosis

Common causeof chronic lung disease in children but also affects other organsystems with epithelial surfaces, especially intestine, pancreas,liver, and sweat glands. Mutations in CFTR gene located on chromosome7 result in abnormal ion transport across epithelial surfaces. Genetictransmission is autosomal recessive.

Age of onset and clinical presentationvary widely. Earliest clinical manifestation is meconium ileus innewborn. Most common manifestation of respiratory disease is coughthat may be dry or productive. Other clinical findings include wheezing;nasal polyps; frequent large, foul-smelling stools; digital clubbing;recurrent rectal prolapse; and poor growth.

Chest radiograph usually shows hyperinflation,irregular aeration with areas of patchy atelectasis, and accentuatedperibronchial markings.

Bacterial organisms that commonly colonizerespiratory tract in this disease are S. aureus, H. influenzae,and gram-negative enteric bacteria, including P. aeruginosa.

Sweat chloride level >60 mEq/Lis diagnostic.

DNA mutation analysis is definitive.

Bronchiectasis

Infectionor chronic inflammation of airways can cause bronchiectasis.

May be focal (foreign body, local infection)or generalized (cystic fibrosis, chronic aspiration).

Chronic productive cough with cracklesand rhonchi on lung exam are usual findings.

Chest radiography may show persistentatelectasis or infiltrates that fail to resolve.

Diagnosis may be confirmed by chestCT, which shows dilated bronchi that do not taper peripherally.

Lung Abscess

May occur ± pneumonia.

Most common organisms found in lungabscesses are Staphylococcus species and group A Streptococcus.Anaerobes also may play role in individuals with aspiration pneumonia.

Persistent fever and cough are usualclinical features.

Abscess (density with air-fluid level)may be seen on chest radiography, with confirmation by chest CT.

Needle aspirate may reveal specificpathogen.

Allergic Disorders

Allergic Rhinitis

Althoughusual clinical findings with allergic rhinitis are persistent orrecurrent rhinorrhea, sneezing, and itchy tearing eyes, nonproductivecough also occurs.

See Chap.41, Nasal Discharge.

Asthma

Definedas inflammatory disorder of smaller airways, which is characterizedby recurrent wheezing that is reversible with bronchodilator therapyor spontaneously. Another common manifestation is recurrent cough, ± wheezing,especially after exercise or at night.

See Chap.75, Wheezing.

Mechanical or Chemical Irritation

Environmental Irritants

Smoke, chemicalfumes, particulate matter from fire, and other environmental pollutantsand toxins may stimulate cough production.

History of exposure is diagnostic.

Foreign Body Aspiration

Aspirationof foreign body into bronchus commonly produces choking or gagging followedby persistent coughing or wheezing.

Some common foreign bodies are food(nuts, seeds, meat), pins, tacks, and plastic tops.

Chest radiography may show segmentalor lobar collapse or unilateral hyperinflation. Chest radiographstaken in inspiration/expiration or in right and left lateraldecubitus positions as well as fluoroscopy may demonstrate unilateralair trapping and movement of mediastinum away from affected side duringexpiration. In some cases, bronchoscopy is necessary to confirmdiagnosis.

Bronchopulmonary Dysplasia

A form ofchronic lung disease that often follows neonatal respiratory distresssyndrome treated with endotracheal intubation, mechanical ventilation,and high concentrations of inspired oxygen.

During course of disease, respiratorydistress waxes and wanes with intermittent cough.

Crackles and rhonchi may be heard onlung exam.

Hypoxemia and hypercapnia occur, andapnea may develop.

Chest radiograph shows combinationof hyperinflation, prominent perihilar markings, and streaky densitiesthat may persist for many months.

Congenital Anomalies

Congenitalanomalies that may produce cough include laryngomalacia, tracheomalacia,tracheoesophageal fistula, pulmonary sequestration, bronchogeniccyst, cystic adenomatoid malformation, and vascular rings and slings.

See Chap.56, Respiratory Distress and Apnea, Chap. 63, Stertor, Stridor, and Airway Obstruction,and Chap. 65, Sucking and SwallowingDifficulty.

Cardiac Failure

Pulmonaryvenous congestion occurring as manifestation of cardiac failuremay cause airway edema leading to cough. Other findings includerespiratory distress, tachycardia, hepatomegaly, and cardiomegaly.

See Chap.7, Cardiac Failure.

Gastroesophageal Reflux

Aspirationof stomach contents into lung may produce airway obstruction andpneumonia with coughing and wheezing. Another proposed mechanismfor cough and respiratory distress is the stimulation of esophagealvagal afferents by gastric contents to produce laryngospasm andbronchospasm.

See Chap.55, Regurgitation and Vomiting.

Swallowing Dysfunction

Disordersthat cause difficulty in swallowing may produce gagging, choking,and recurrent coughing.

See Chap.65, Sucking and Swallowing Difficulty.

Immotile Cilia Syndrome

Autosomal-recessivedisorder characterized by defects in ultrastructure of cilia that impairciliary motion and clearance of mucus from respiratory tract.

1 form of this syndrome has been mappedto chromosome 9p21-p13, whereas another has been mapped to chromosome5p.

Structural defects include absenceof dynein arms and radial spokes.

Onset is in infancy or early childhoodwith chronic cough that is usually productive of sputum. Other manifestationsinclude chronic rhinitis, sinusitis, otitis media, bronchitis, andpneumonia.

Chest radiograph may show hyperinflation,bronchial wall thickening, segmental atelectasis or consolidation,situs inversus, and bronchiectasis.

Electron microscopy of cilia obtainedby nasal or bronchial biopsy brushing techniques demonstrates structuraldefects.

Neoplasm

Chroniccough may occur with airway tumors (hemangioma, papilloma), mediastinal masses,and lung tumors, including metastatic lesions.

See Chap.56, Respiratory Distress and Apnea.

Reflex Cough

In somechildren, foreign body or cerumen in ear canal causes transientreflex cough.

Persistent cough also has been attributedto hair lodged against tympanic membrane.

Otoscopic exam is diagnostic.

Psychogenic/Habitual Cough

Occasionallychild has persistent or recurrent cough with no evidence of underlying respiratorytract disease. Usually occurs in school-aged child after URI, andcough lasts for weeks.

Cough is usually loud, harsh, and foghorn-like,disappearing during sleep and often decreasing when alone or onweekends.

Otherwise, child is well and physicalexam and chest radiograph are normal.

Often secondary gain can be identified.Some of these children may have emotional problems that requirefurther evaluation.

Diagnostic Approach

In manycases history and physical exam are diagnostic.

Age of child, duration of cough, qualityand characteristic features of cough, and associated findings narrowdiagnostic possibilities.

Age of Child and Duration of Cough

In infantsand preschool children, most common causes of acute cough are viralURI, pneumonia (viral, bacterial, aspiration), laryngotracheobronchitis(croup), bronchiolitis, and foreign body aspiration.

In school-aged children and adolescents,most common causes of acute cough are viral URI, bronchitis, andpneumonia (viral, bacterial, M. pneumoniae).

Chronic cough lasts >3–4wks, although many coughs induced by acute viral URIs may persistfor a number of weeks after onset of infection.

Most common causes of persistent coughin early infancy are pertussis, pneumonia (infection, aspiration),and cystic fibrosis.

In later infancy and early childhood,recurrent viral URIs and asthma are most common causes of recurrentcough.

Most common causes of recurrent orchronic cough in adolescents are asthma, smoking, cystic fibrosis,and psychologic problems.

Periodicity and Quality of Cough

Asthma,pneumonia, cystic fibrosis, bronchiectasis, TB, and focal lesionscausing local irritation or infection cause persistent coughs.

Recurrent viral URIs and asthma causeepisodic coughing.

Paroxysmal cough suggests pertussisbut can also occur with Chlamydia and Mycoplasma infection.

Dry, barking or brassy cough with voicechanges signifies laryngotracheal pathology.

Loud, honking cough in older childthat disappears with sleep suggests habit or psychogenic cough.

Neuromuscular disorders produce a weakand feeble cough.

Loose rattling cough means that excesssecretions or exudate exist in airways. Moist cough with sputumproduction is hallmark of suppurative lung disease.

Timing of Cough

If coughdisappears while asleep, it usually has psychologic basis.

Recurrent episodes of nocturnal coughor after exertion suggest cough-variant asthma.

Productive cough with morning awakeningis common with bronchitis secondary to smoking or cystic fibrosis.

Nature of Sputum Production

Few infants or young children expectorate.Cough productive of purulent sputum is usually associated with bacterialpneumonia, cystic fibrosis, bronchiectasis, or lung abscess. Occasionally,the sputum is blood streaked.

Associated Findings

Presenceof fever suggests infectious process such as viral URI, pneumonia,croup, pertussis or TB.

Hemoptysis suggests bronchitis, foreignbody, bronchiectasis, cystic fibrosis, TB, pulmonary hemosiderosis,or lung abscess.

Cough associated with stridor indicatesairway obstruction.

Evaluation

Etiologyof cough can usually be determined or at least suspected from historyand physical exam.

Chest radiography shows pattern andextent of disease and is confirmatory in many instances.

With suspected bacterial pneumonia,CBC and differential, blood culture, and sputum culture (older child)should be performed.

If TB is suspected, intermediate-strengthPPD should be placed.

Thoracentesis should be performed ifthere is significant pleural effusion because Gram and acid-faststains, cultures (viral, bacterial, fungal), PCR, and cytology mayprovide specific diagnosis.

With segmental or lobar collapse unresponsiveto therapy, bronchoscopy should be performed to define obstructivelesion and to obtain cultures.

Another useful test is sweat test inchildren with recurrent or chronic cough.

With suspected pulmonary infectionin immunocompromised host, nasal wash cultures for viruses, andsputum and blood cultures for bacteria and fungi, should be performed.Empiric therapy may be started for gram-positive and gram-negativebacteria and for P. carinii infection, but bronchoscopy with bronchoalveolarlavage should be considered at early stage. If this is nondiagnostic,lung biopsy is next step.

» READ BOOK EXCERPT ONLINE »

Source: The Diagnostic Approach to Symptoms and Signs in Pediatrics, 2006

Fever: Clinical Features and Diagnosis: Acute Fever
(The Diagnostic Approach to Symptoms and Signs in Pediatrics)

Common Causes

Infectious

Infectious causes of acute fever are listedbelow and discussed in other chapters.

Respiratorytract

Upperrespiratory tract infection (common cold)

Pharyngitis

Tonsillitis

Otitis media

Herpes gingivostomatitis

Herpangina

Sinusitis

Croup

Bronchiolitis

Bronchitis

Pneumonia (viral, bacterial, mycoplasma)

Pertussis

Gastrointestinal

Gastroenteritis

Appendicitis

Hepatitis

Genitourinary

Urinary tract infection (includingpyelonephritis)

Sexually transmitted diseases

Musculoskeletal

Septic arthritis

Osteomyelitis

Myositis

Central nervous system

Meningitis(viral, bacterial)

Viral encephalitis

Infections associated with prominentrash

Roseola

Hand-foot-mouth syndrome

Varicella

Erythema infectiosum (parvovirus B19)

Measles

Scarlet fever

Meningococcemia

Rocky Mountain spotted fever

Other

Viral illnesses

Septicemia/bacteremia

Infectious mononucleosis

Lymphadenitis

Cellulitis/abscess

Cat scratch disease

Dental abscess

Periorbital cellulites

Parotitis

Noninfectious

Drug Reactions

Hypersensitivityreactions are responsible for most cases of drug fever.

Although fever can occur without otherfindings, urticarial rash and peripheral eosinophilia make diagnosismore likely.

Vaccine Reactions

Reactionsto acellular pertussis vaccine can produce fever but are uncommon.

Within 7–10 days after administrationof live measles vaccine or measles, mumps, rubella (MMR) vaccine,fever can occur and is often associated with macular or papular rash.

Trauma

Crush injuries and fractures of large bonescan cause fever due to large amount of tissue damage and releaseof inflammatory mediators.

Burns

Fever may occur with severe burns, even inabsence of infection, because of fluid losses and resetting of thermoregulatorycenter. Severe sunburn also may cause fever.

Kawasaki Disease

Definedas vasculitis of unknown cause that usually occurs in children <5yrs of age.

Diagnostic criteria are absence ofany other disease process and presence of fever for ≥5 days associatedwith 4 of 5 signs:

Bilateral conjunctival injection

Cervical lymphadenopathy

Macular or papular rash primarily ontrunk

Mucous membrane involvement with dry,fissured lips, strawberry tongue, or pharyngeal injection

≥1 change in extremities, includingpalmar erythema, edema, and periungal or generalized desquamation

Lab findings include leukocytosis,pyuria, proteinuria, spinal fluid pleocytosis, elevation in serumaminotransferases, and increased erythrocyte sedimentation rate.

Chest radiograph may show small pleuraleffusions.

Platelet count may be normal at onset,but thrombocytosis usually occurs during second week of illness.

Complications include coronary arteryaneurysms, myocarditis, and myocardial infarction.

2-D echocardiography may reveal coronaryartery aneurysms within 1–2 cm of origin of coronary arteriesfrom aorta.

Uncommon Causes

Infectious

Many infections in this category, as listedbelow, are discussed in other chapters.

Respiratorytract

Viral(hantavirus pulmonary syndrome)

Bacterial [supraglottitis,bacterial tracheitis, abscess (peritonsillar, retropharyngeal, lateral pharyngeal),tuberculosis, actinomycosis, nocardiasis, Legionella]

Fungal (aspergillosis, blastomycosis,histoplasmosis, coccidioidomycosis)

Parasitic (P. carinii)

Gastrointestinal

Amebiasis

Pancreatitis

Cholecystitis

Cholangitis

Peritonitis

Intraabdominal abscess

Genitourinary

Epididymitis

Orchitis

Abscesses (perinephric, tuboovarian)

Cardiac

Acute rheumatic fever

Myocarditis

Pericarditis

Endocarditis

Central nervous system (brain abscess)

Other

Viral (HIV, rabies)

Bacterial [staphylococcalscalded skin syndrome, toxic shock syndrome, orbital cellulitis/abscess,Borrelia (relapsing fever), brucellosis, leptospirosis, plague,psittacosis (ornithosis), rat-bite fever, syphilis, tularemia, tetanus]

Fungal (disseminated histoplasmosis,nonpulmonary blastomycosis)

Parasitic [malaria, ascariasis,toxocariasis (visceral larva migrans, ocular larva migrans), toxoplasmosis,trichinosis]

Rickettsial [endemic typhus(murine), epidemic typhus (louse-borne typhus), Q fever, rickettsialpox, ehrlichiosis]

Hantavirus Pulmonary Syndrome

Can occurafter exposure to infected rodents (most commonly, deer mouse),their saliva, or excreta.

Characterized by acute onset of fever,headache, myalgia, cough, vomiting, and diarrhea followed by developmentof hypotension and noncardiogenic pulmonary edema. Leukocytosiswith immature granulocytes, thrombocytopenia, and elevated Hct arefrequent findings.

Reverse-transcriptase polymerase chainreaction or enzyme immunoassay can detect viral antigen from clinicalsamples. Diagnosis also can be confirmed serologically.

Borrelia (Relapsing Fever)

Caused byspirochetes of Borrelia. Infected ticks (Ornithodoros species) andlice (P. humanus) are sources of human infections. Most cases inU.S. are transmitted by ticks, which become infected by feedingon rodents and other small mammals.

Incubation period of 7–10days is followed by fever, headache, chills, myalgia, and arthralgia,which may last up to 1 wk. Transient macular rash, petechiae ofskin, jaundice, and hepatosplenomegaly may occur.

Complications include pneumonia, myocarditis,and meningitis. After 5- to 10-day interval, relapse occurs withfever and same clinical findings as described above.

Spirochetes can be seen by dark-fieldmicroscopy and in Wright-stained smears of peripheral blood. Positiveblood culture is also diagnostic.

Brucellosis

Transmittedby direct contact with infected animals (goats, sheep, cows, swine)or by ingestion of contaminated milk or milk products produced bythem.

Onset can be acute or insidious, withfever, headache, abdominal pain, arthralgia, myalgia, weight loss,lymphadenopathy (especially cervical and axillary), and hepatosplenomegaly.Prolonged fever without any other findings sometimes occurs.

Complications include meningitis, osteomyelitis,and endocarditis.

Organism can sometimes be culturedfrom blood, urine, spinal fluid, bone marrow, or lymph node. Ifthese cultures are negative, diagnosis depends on serologic findings.Serum agglutination test with antibody titer ≥1:160 or 4-foldincrease in agglutination titer on serial samples is diagnostic.

Leptospirosis

L. interrogansinfects humans through contact with animal urine in contaminated foodor water. Incubation period is 2–20 days.

Acute illness usually consists of fever,headache, chills, malaise, myalgia, vomiting, lymphadenopathy, andabdominal pain. Hepatic (hepatomegaly, jaundice, liver failure),renal (azotemia, renal failure), and CNS dysfunction (aseptic meningitis,alteration in consciousness) may follow.

Diagnosis confirmed by positive blood,urine, or spinal fluid cultures; 4-fold increase in serial agglutinationtiters; or visualization of spirochete by dark-field microscopyof urine.

Plague

Y. pestisis responsible for plague. Most common form is bubonic plague, whichis usually transmitted by bites of infected fleas and uncommonlyby contact with infected tissues and fluids of wild rodents (e.g.,prairie dogs, ground squirrels, chipmunks, hares, rabbits, and rats).

Characterized by fever and painfulregional adenopathy, usually involving cervical, inguinal, or axillarylymph nodes (buboes).

Less common forms include pneumonicplague (cough, fever, dyspnea, hemoptysis), septicemic plague (fever,hypotension, coagulopathy), and meningeal plague (fever, headache,photophobia, seizures).

Positive fluorescent antibody testof sputum, lymph node aspirate, blood, or spinal fluid is presumptiveevidence of infection. Serologic tests also may confirm diagnosis.Positive sputum, lymph node, blood, or spinal fluid cultures aredefinitive.

Psittacosis (Ornithosis)

C. psittacicauses psittacosis, which is transmitted from parrots and otherrelated species (parakeets, finches, cockatoos), and ornithosis,which is acquired from turkeys, pigeons, ducks, chickens, and otherfowl. Transmission is by inhalation of organisms from infected bird'senvironment. Incubation period is usually 1–2 wks.

Affected individuals have acute respiratorytract infection with fever and nonproductive cough.

Chest radiograph usually shows interstitialpneumonia. Usual method of diagnosis is serologic, with 4-fold increasein complement fixation antibody titer. With compatible clinicalpicture, single complement fixation titer ≥1:32 is also considereddiagnostic.

Rat-Bite Fever

May followrodent bite, usually that of rat.

2 different organisms, S. moniliformis,which is more common in U.S., and S. minus, which is more commonin Japan, can cause this infection.

Clinical features include fever, chills,headache, muscle pain, and rash (macular, papular, or petechial).

Migratory polyarthritis/arthralgiasoccur in some cases of S. moniliformis infection. Complicationsinclude pneumonia, meningitis, myocarditis, pericarditis, endocarditis,and soft tissue or solid organ abscesses. Positive culture fromsite of bite, blood, or joint fluid confirms diagnosis.

With S. minus infection, the bite maybe followed by ulceration, lymphadenopathy, and rash composed ofpurple or red plaques. Diagnosis of S. minus may be confirmed byobservation of organisms by dark-field microscopy in wet mountsof blood, exudate of lesion, and lymph nodes.

Syphilis

T. pallidumcauses syphilis, which may be congenital or acquired. See Chap. 36, Jaundice, fordiscussion of congenital syphilis.

Acquired syphilis almost always occursby sexual transmission.

Incubation period is 10–90days.

In primary stage, ≥1 painless ulcer(chancres) occurs on skin or mucous membranes at site of inoculation,usually on genitalia.

During secondary stage, which occurs1–2 mos later, generalized macular or papular rash appears,usually involving palms and soles. Fever, malaise, headache, arthralgia,generalized adenopathy, splenomegaly, and condyloma lata also canoccur.

Tertiary stage occurs several yearsto decades later and is characterized by aortitis or gummatous changesof skin, bones, or viscera.

Neurosyphilis can occur at any stage.

Nontreponemal reagin antibody test(rapid plasma reagin card test) and VDRL slide test, which measureimmunoglobulins directed against cardiolipin antigen, are usefulscreening tests.

Any positive test result should beconfirmed by 1 treponemal test.

Specific treponemal antibody serologictests include fluorescent treponemal antibody absorption test (FTA-ABS),which usually remains positive for life, even with successful therapy.

Microscopic dark-field exam of lesionscraping or lymph node aspirate that shows spirochetes or positivedirect fluorescent antibody test of lesion exudate or tissue isalso diagnostic.

Diagnosis of CNS involvement is establishedby positive CSF VDRL or FTA-ABS tests. CSF pleocytosis and increasedCSF protein concentration also may be found.

Tularemia

Source ofinfection with F. tularensis is infected animal or carcass, usuallyrabbit. Infection is acquired by ingestion of contaminated meator water, handling infected animals, or bites by dog ticks or deerflies that have come into contact with infected animal.

Fever, chills, headache, and myalgiaare usual findings. Common presentation is ulceroglandular syndromewith painful, swollen, ulcerating papule and inflamed lymph nodesthat may drain spontaneously.

Other syndromes are glandular (absenceof skin or mucous membrane involvement); oculoglandular (conjunctivitisand preauricular lymph node involvement); oropharyngeal (exudativepharyngitis); typhoidal (fever and hepatosplenomegaly); and pneumonic(cough).

Positive culture or 4-fold increasein serum agglutinin titer is diagnostic.

Malaria

Sporozoaof genus Plasmodium cause malaria, which occurs in many tropicaland subtropical countries. Bite by infected female Anopheles mosquitotransmits infection. 4 known types of malaria are caused by differentspecies and have the following incubation periods:

P. falciparum,9–14 days

P. vivax, 12–17 days

P. ovale, 16–18 days

P. malariae, 18–40 days

P. falciparum and P. vivax infectionsare most common, whereas P. falciparum infection is most serious.Mixed infections with more than 1 type also occur.

Typical symptoms are fever with chills,sweats, and headache. Fever usually occurs every other day withP. vivax, P. falciparum, and P. ovale infections, and every thirdday with P. malariae infection. Vomiting, diarrhea, cough, and abdominalpain are other manifestations. Significant hemolysis produces pallorand jaundice. Hepatosplenomegaly may occur with chronic infection.

Clinical syndromes that may occur withP. falciparum infection include

Febrile illness without specific or localizingsigns

Severe anemia

Respiratory failure ± pulmonaryedema

Renal failure secondary to acute tubularnecrosis

Cerebral malaria with seizures andalteration of consciousness

Vascular collapse and shock associatedwith adrenal insufficiency

P. vivax and P. ovale may cause anemiaand hypersplenism, whereas nephrotic syndrome may be associatedwith P. malariae infection. Any type can cause congenital malaria,which is characterized by fever, irritability, and lethargy.

Analysis of thick and thin blood smearsusing Wright or Giemsa stain identifies parasite and confirms diagnosis.

Ascariasis

Infectionwith roundworm A. lumbricoides is usually asymptomatic, but diarrhea, vomiting,and abdominal pain sometimes occur. Larval migration through lungcan cause transient pneumonitis associated with fever and eosinophilia.

Adult worms, which are whitish brownin color and 15–30 cm (males) or 20–40 cm (females)long, sometimes pass through rectum.

Identification of ova by microscopicidentification of stool or adult worm is diagnostic.

Toxocariasis (Visceral Larva Migrans, Ocular Larva Migrans)

Dog roundwormT. canis and cat roundworm T. cati cause toxocariasis.

Ingestion of infective eggs from soilcauses human infection, which is most common in toddlers.

Although infection can be asymptomatic,with eosinophilia as its only manifestation, other findings includefever, cough, macular or papular rash, and hepatosplenomegaly. Pneumonia,myocarditis, and encephalitis are rare complications. Ocular invasionusually occurs without other evidence of infection.

Enzyme immunoassay for serum Toxocaraantibodies available through CDC is both sensitive and specificfor visceral larva migrans and less sensitive for ocular larva migrans.Liver biopsy also may detect larvae, but yield is low.

Trichinosis

Infectionwith nematode T. spiralis is acquired by eating undercooked meat(usually pork) containing encysted larvae.

Fever, diarrhea, vomiting, and abdominalpain follow in 1–7 days. During next 2–8 wks,fever, myalgia, urticarial rash, and hemorrhages (conjunctival andsubungual) may develop. Eosinophilia as high as 70% alsomay occur. Most serious complication is myocarditis.

Identification of larvae in suspectmeat is fastest way to diagnose. Diagnosis also can be made by visualizinglarvae in muscle biopsy or by increase in paired acute and convalescentantibody titers.

Endemic Typhus (Murine)

Murine typhuscaused by R. mooseri is primarily infection of rats. Transmissionto humans occurs by bite of infected rat or inhalation of infectedrat excreta 1–2 wks after exposure. Infection occurs insoutheastern U.S. and is more common during summer months.

Fever, headache, and myalgia are usualfindings. Macular or papular rash occurs about 1 wk into illness,which lasts 2–3 wks.

Diagnosis is usually confirmed by serologictests.

Epidemic Typhus (Louse-Borne Typhus)

Humans areonly known reservoir of R. prowsekii, which causes epidemic typhus.

Infection is transmitted by infectedbody louse feces, usually through skin abrasion. Crowding, poorpersonal hygiene, and poverty are factors that contribute to itsoccurrence.

Usual incubation period is 1–2wks.

Begins with sudden onset of fever,chills, headache, and myalgia. Macular or papular rash appears in3–7 days and is followed by petechial or hemorrhagic rash.Face, palms, and soles are usually spared. In severe cases pneumonia,renal failure, and alteration in consciousness may occur.

Diagnosis may be confirmed by isolationof organism, visualization of rickettsiae in tissues, detectingrickettsiae by polymerase chain reaction, or by serologic testing.

Q Fever

Caused byC. burnetii, which infects cattle, sheep, goats, and rodents.

Human infection follows inhalationof infected dust from exposure to hides or products of conceptionof these animals.

Incubation period is 10–20days.

Acute onset of fever, chills, headache,and weakness are characteristic. Hepatosplenomegaly and weight lossoften occur. Persistent cough may signify pneumonia. High, spikingfever may continue for 1–3 wks, with gradual resolution.Major manifestations of chronic disease are hepatitis and endocarditis.

Immunofluorescence, complement fixation,enzyme immunoassay, and immune adherence hemagglutination antibodytests are used diagnostically.

Rickettsial Pox

Definedas mild illness caused by R. akari.

House mice harbor this organism, whichis transmitted to humans by mites.

Incubation period is 2–7 daysfollowing attachment of infected mite.

Mite bite produces red papule, whichforms vesicle that ulcerates. Fever, headache, chills, sweats, myalgia,and papular/vesicular eruption follow in 1–3 days.

During acute stage, organism may beisolated from blood. Serologic tests are also diagnostic.

Ehrlichiosis

Consistsof at least 2 distinct diseases: human monocytic ehrlichiosis causedby E. chaffeensis and human granulocytic ehrlichiosis caused byan unnamed Ehrlichia species. Both are transmitted by tick vectors.

Both resemble Rocky Mountain spottedfever, with fever, headache, malaise, chills, and myalgia. Macularor papular rash that occasionally can be petechial occurs commonlywith monocytic form and rarely with granulocytic form.

Lab findings include anemia, thrombocytopenia,increased liver aminotransferases, and CSF pleocytosis with predominanceof lymphocytes.

Diagnosis may be confirmed by serologicmethods or by polymerase chain reaction of DNA from a clinical sample.

Noninfectious

Many uncommon noninfectious causes, as listedbelow, are discussed in other chapters.

Respiratory

Pulmonaryinfarction

Pulmonary embolism

Gastrointestinal

Intestinal obstruction

Inflammatory bowel disease

Cardiac (postpericardiotomy syndrome)

Hematologic

Intravascular hemolysis

Bleeding into closed space

Endocrine

Thyrotoxicosis

Diabetes insipidus

Central nervous system

Intracranialinjury and hemorrhage

Spinal cord injury

Hypothalamic and brain stem lesions

Status epilepticus

Neoplasia

Leukemia

Lymphoma

Neuroblastoma

Pheochromocytoma

Connective tissue disorders

Juvenile rheumatoidarthritis

Systemic lupus erythematosus

Polyarteritis nodosa

Polymyositis

Dermatomyositis

Mixed connective tissue disease

Poisonings

Atropine

Cocaine

Salicylate

Lysergic acid diethylamide

Hydrocarbons

Organophosphates

Tricyclic antidepressants

Amphetamines

Phenothiazines

Other

Spider bites (black widow, brown recluse)

Stevens-Johnson syndrome

Heat-related illness

Serum sickness

Anhidrotic ectodermal dysplasia

Familial dysautonomia

Sarcoidosis

Familial Mediterranean fever

Factitious fever

Central Nervous System

Increasedtemperature may occur with intraventricular hemorrhage as well assubdural hematoma or effusion. CT is diagnostic.

Absence of effective control mechanismsof temperature regulation sometimes results from spinal cord injury.In such cases, significant increase in environmental temperatureproduces hyperpyrexia.

Any hypothalamic or brainstem lesionmay damage hypothalamic temperature-regulating center and producehyperpyrexia. Hypoxic-ischemic encephalopathy and brain tumors arecommon examples.

Prolonged status epilepticus may resultin autonomic changes with associated increase in temperature.

Neoplasia

Fever in children with cancer usually occursbecause of underlying disease process, infection, or effects oftreatment. Important factor in determining risk of serious infection,especially bacterial infection, is neutropenia (absolute neutrophilcount <500 cells/mm³).

Other

Spider Bites

Bite ofbrown recluse spider (L. reclusa) can cause severe local reaction,with fever, pain, and swelling followed by blister formation andnecrosis. Spider is brown, 10–15 mm long, with 6 eyes arrangedin an arc.

Female black widow spider (L. mactans)has red ventral spot and variable red dorsal spots. Usual lengthis about 2 cm, and bite produces twin red fang marks in skin. Injectionof venom produces pain and swelling at site of bite. Vomiting, fever,and intense abdominal pain may occur within 30 mins.

History and identification of spiderconfirm diagnosis.

Serum Sickness

Occurs 1–2wks after exposure to animal serum (e.g., diphtheria antitoxin;botulism antitoxin types A, B, and E; and antivenoms for snake orspider bites). Accelerated reaction may occur within 1–5days in individuals who have had previous exposure.

Clinical manifestations include fever;macular, papular, erythematous, or urticarial rash; localized orgeneralized adenopathy; hepatosplenomegaly; vomiting; abdominalpain; arthralgia or arthritis; and generalized edema. Usually self-limitedillness and lasting few days to few weeks.

Factitious Fever

Sometimes parent or guardian fabricates andreports persistent fever in child. Clues to this diagnosis are

Lack oftachycardia, flushing, sweating, or warm skin at time of fever

Rapid appearance and disappearanceof high fever in child who is otherwise well

Absence of fever when nurse or physiciantakes temperature

Wide discrepancy between oral and rectaltemperatures when taken simultaneously.

In any of these situations, consider Munchausensyndrome by proxy.

Diagnostic Approach: Acute Fever

Most acutefevers are caused by infection, usually viral or bacterial.

Common infections should be consideredbefore less common ones, unless clinical findings suggest otherwise.

Best guide to accurate diagnosis ishistory and physical exam.

Clinical Findings

Age of child,height of fever, compromised host defenses, and associated findings (e.g.,rash, painful extremity, abdominal pain, jaundice, generalized lymphadenopathy,hepatomegaly, or splenomegaly) are important factors in diagnosisof any child who presents with fever.

Important historical information includesany history of contact with other ill individuals, foreign travel,previous immunizations, drug exposure, history of pica, and exposureto animals or birds.

History of pica suggests toxoplasmosis or toxocariasis(visceral larva migrans).

History of tick exposure suggests RockyMountain spotted fever, relapsing fever, or Lyme disease.

History of exposure to animals or birdssuggests diseases caused by rats (plague, rat-bite fever, leptospirosis);hamsters (lymphocytic choriomeningitis encephalitis); rabbits (tularemia);cattle, goats, and dogs (brucellosis); cats (cat scratch disease,toxoplasmosis); and birds (psittacosis).

Age

Risk ofserious bacterial illness (e.g., septicemia and meningitis) varieswith age and is greatest during immediate neonatal period, especiallyin premature infants.

Clinical findings may be nonspecific,including poor feeding, decreased activity, fever, or hypothermia.

In such infants, CBC with differentialand blood, urine, and spinal fluid cultures should be performed.

Gram-stained smear of spinal fluidshould be performed and antigen studies considered.

Chest radiograph should be performedwith history of respiratory symptoms.

Stool culture should be performed withhistory of diarrhea.

Height of Fever

In infants,incidence of serious bacterial infection is higher in those withrectal temperature >41°C compared with those withlower temperature.

Preschool and school-aged childrenoften have high fever that persists for several days and is notassociated with localizing findings. Such children do not appearvery ill and usually have self-limited viral infections.

Continued observation with close follow-upusually clarifies many of these problems.

Whatever the height of fever, assessmentof toxicity and level of functioning is crucial in diagnosis andmanagement.

Compromised Host Defenses

Children with impaired host defenses dueto primary or secondary immunodeficiency disorders are at risk fordevelopment of serious infection caused by wide range of infectiveagents, including bacteria (S. aureus, gram-negative enteric organisms),viruses (cytomegalovirus, VZV), protozoa (P. carinii), and fungi(Candida and Aspergillus species).

Associated Physical Findings

Fever and Rash

Macularor papular rashes occur with viral infection (enteroviruses, herpesvirus6, measles virus, rubella virus, parvovirus B19, Epstein-Barr virus),bacterial infection (scarlet fever, meningococcemia, toxic shocksyndrome, typhoid fever, rat bite fever, leptospirosis), rickettsialinfection (Rocky Mountain spotted fever), Kawasaki disease, anddrug reactions (most commonly penicillins and sulfonamides).

Erythematous rashes occur with viralinfection (parvovirus B19), bacterial infection (scarlet fever,toxic shock syndrome, staphylococcal scalded skin syndrome), Kawasakidisease, and reactions to same drugs causing macular or papularrashes.

Petechial and purpuric rashes occurwith congenital viral infection (rubella virus, cytomegalovirus),other viral infection (enteroviruses, Epstein-Barr virus, arboviruses),bacterial infection (group A Streptococcus, N. meningitidis, S.pneumoniae, N. gonorrhoeae, S. aureus, H. influenzae type b, P. aeruginosaand other gram-negative enteric bacteria), rickettsial infection(Rocky Mountain spotted fever), and parasitic infection (toxoplasmosis).

Vesicular rashes occur with viral infection(herpes simplex virus, varicella-virus infection, enteroviruses)and bacterial infection (bullous impetigo, staphylococcal scaldedskin syndrome).

See Chap.60, Skin Lesions and Rashes.

Fever and Painful Extremity

Infectiousor inflammatory causes

Cellulitis

Septic arthritis

Osteomyelitis

Transient synovitis

Skin/soft tissue abscess

Thrombophlebitis

Acute rheumatic fever

Vaccine immunization

Other causes

Neoplasia (leukemia, osteogenic sarcoma,Ewing sarcoma, metastatic neuroblastoma)

Collagen vascular disease (juvenilerheumatoid arthritis, systemic lupus erythematosus)

Kawasaki disease

Serum sickness

Arthritis associated with inflammatorybowel disease

See Chap.37, Limp.

Fever and Abdominal Pain

Infectiousand inflammatory causes

Nonspecific viral illness

Gastroenteritis

Urinary tract infection

Pneumonia

Appendicitis

Intraabdominal abscess

Hepatitis

Peritonitis

Cholecystitis

Cholangitis

IBD

Pelvic inflammatory disease

Pancreatitis

Generalized vasculitis

Other causes

Neoplasia (leukemia, Hodgkin disease,non-Hodgkin lymphoma, neuroblastoma, hepatic malignancies)

Diabetic ketoacidosis

Black widow spider bite

See Chap.2, Abdominal Pain.

Fever and Jaundice

Most commoncause of fever and unconjugated hyperbilirubinemia in neonates is septicemia.Causes of fever and conjugated hyperbilirubinemia in neonates include

Viral infection(rubella virus, cytomegalovirus, herpes simplex virus, VZV, enteroviruses,hepatitis B virus)

Bacterial infection (septicemia, syphilis)

In infancy and childhood, fever andconjugated hyperbilirubinemia may be due to

Viral infection (hepatitis A, B, C,D, E; enteroviruses; herpes simplex virus; Epstein-Barr virus; cytomegalovirus

Bacterial infection (septicemia, cholecystitis,cholangitis, liver abscess, leptospirosis, brucellosis)

Rickettsial infection (Q fever)

Fungal infection (histoplasmosis)

Parasitic infection (amebiasis, malaria,visceral larval migrans)

Drug reactions

Neoplasia (hepatic malignancies, non-Hodgkinlymphoma)

See Chap.36, Jaundice.

Fever and Generalized Lymphadenopathy

Infectiouscauses

Viralinfection (rubella virus, measles virus, Epstein-Barr virus, cytomegalovirus, VZV,hepatitis A virus, HIV)

Bacterial infection (pyogenic infectionfrom S. aureus, group A Streptococcus, H. influenzae type b, S.pneumoniae; tuberculosis; brucellosis; tularemia; salmonellosis;leptospirosis; syphilis)

Fungal infection (histoplasmosis)

Parasitic infection (toxoplasmosis,malaria)

Noninfectious causes

Neoplasia(leukemia, non-Hodgkin lymphoma, metastatic neuroblastoma)

Langerhans histiocytosis

Collagen vascular disease (juvenilerheumatoid arthritis, systemic lupus erythematosus)

Drug reactions

Serum sickness

Chronic granulomatous disease

Sarcoidosis

See Chap.38, Lymphadenopathy.

Fever with Hepatomegaly, Splenomegaly, or Hepatosplenomegaly

Causes offever and hepatomegaly

Hepatitis (A, B, C, D, E)

Primary liver abscess

Amebiasis

Primary liver malignancies

Causes of fever and splenomegaly

Viral infection(rubella virus, cytomegalovirus, herpes simplex virus, enteroviruses, Epstein-Barrvirus)

Bacterial infection (septicemia, endocarditis,tularemia, plague, salmonellosis, splenic abscess)

Rickettsial infection (Rocky Mountainspotted fever)

Parasitic infection (malaria, toxoplasmosis)

Infectious causes of fever and hepatosplenomegaly

Viral infection(rubella virus; herpes simplex virus; cytomegalovirus; VZV; enteroviruses;Epstein-Barr virus; hepatitis A, B, C, D, E)

Bacterial infection (septicemia, endocarditis,brucellosis, tuberculosis, syphilis, leptospirosis, relapsing fever)

Fungal infection (histoplasmosis, coccidioidomycosis)

Parasitic infection (visceral larvalmigrans, toxoplasmosis, Chagas disease)

Other causes of fever and hepatosplenomegaly

Neoplasia(leukemia, Hodgkin disease, non-Hodgkin lymphoma, neuroblastoma)

Langerhans histiocytosis

Collagen vascular disease (juvenilerheumatoid arthritis, systemic lupus erythematosus)

See Chap.30, Hepatomegaly and Chap. 62, Splenomegaly.

Fever without Localizing Signs

Most childrenwith fever and no apparent focus of infection have self-limitedviral infection that resolves without treatment and has no sequelae.

Small percentage of children with acuteonset of fever ≥39°C and no localizing signs, especiallyat 3–36 mos, may have urinary tract infection, bacteremia,or meningitis.

In infants <1 mo of age, commoncauses of septicemia and meningitis are group B Streptococcus andgram-negative enteric bacteria, commonly E. coli. Much less commonis infection with L. monocytogenes.

At 1–3 mos of age, most commoncauses of septicemia and meningitis are S. pneumoniae, group B Streptococcus,and N. meningitidis.

In children >3 mos of age,S. pneumoniae, N. meningitidis, and Salmonella species (usually occurringwith gastroenteritis) cause most bacterial infections that occurwithout a focus.

Diagnostic and management approachto child with fever without apparent focus of infection dependson age, exposure history, usual pathogens, and severity of illness.

See references at end of chapter forfurther information.

Lab Findings

Lab tests(cultures and radiographs most commonly) are used to confirm diagnostic impressionof infection.

WBC and differential may suggest bacterialor viral infection, but they are not diagnostic. WBC count >20,000/mm³ withpredominance of neutrophils (>70%) or <5,000/mm³ withlarge number of band forms (>5%–10%)suggests bacterial infection. Although similar WBC counts sometimeoccur with viral infections, in such cases there is usually predominanceof lymphocytes and few band forms.

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Source: The Diagnostic Approach to Symptoms and Signs in Pediatrics, 2006

Respiratory Distress and Apnea: Clinical Features and Diagnosis: Respiratory Distress (Neonatal)
(The Diagnostic Approach to Symptoms and Signs in Pediatrics)

Upper Respiratory Tract Obstruction

Disorders that cause upper respiratory tractobstruction are discussed in Chap.63, Stertor, Stridor, and Airway Obstruction.

Lower Respiratory Tract Disorders

Transient Tachypnea of the Newborn

Delayedresorption of lung fluid or mild immaturity of surfactant systemare most probable explanations for this disorder, which usuallyoccurs in term infants soon after birth.

Respiratory rate is commonly 60–80breaths/min but sometimes is >100 breaths/min.Mild intercostal retractions and expiratory grunting also may occur.

Characteristic chest radiographic findingsare prominent perihilar markings, hyperaeration, widening of interlobarfissures, and evidence of interstitial and pleural fluid.

Most infants require <40% supplementaloxygen. Tachypnea usually resolves in 3 or 4 days.

Respiratory Distress Syndrome (Hyaline Membrane Disease)

Respiratorydistress syndrome, which is most common cause of respiratory distress inpreterm infants, is due to inadequate amount of surfactant. Someinfants experience intrapartum asphyxia and fail to expand theirlungs at birth, whereas others develop tachypnea and expiratorygrunting within first 1–2 hrs of life.

Spectrum of disease varies from mild(tachypnea and minimal oxygen requirement) to severe (apnea andrespiratory failure). Crackles may be heard on chest exam.

Characteristic chest radiograph showsdiffuse reticulogranular infiltrates, atelectasis, and air bronchograms.

Diagnosis is clinical and radiographic.

Meconium Aspiration and Other Aspiration Syndromes

Neonateswho aspirate meconium are usually those who have had intrapartumasphyxia.

Thick meconium in upper airway andmeconium staining of skin and nails are usual findings. Airway obstruction,pneumonia, and respiratory failure can occur.

Chest radiography shows irregular distributionof coarse, patchy infiltrates and hyperaeration.

Clinical and radiologic findings arediagnostic.

Aspiration of feedings sometimes occursin normal infants but is more frequent in those with sucking andswallowing disorders (see Chap.65, Sucking and Swallowing Difficulty).

Pneumonia

Pneumoniamay be caused by infections acquired transplacentally, during birthprocess, and postnatally. Viral infections transmitted by transplacentalroute include enteroviruses, adenoviruses, influenza viruses, rubellavirus, varicella-zoster virus, herpes simplex virus, cytomegalovirus,and HIV. Transplacental bacterial infections caused by L. monocytogenes,M. tuberculosis, or T. pallidum are less common than viral infections.

Neonatal pneumonia is most commonlyacquired during birth process. Group B Streptococcus is most commonpathogen; other pathogens (e.g., gram-negative enteric bacteria)are less common. Most common viral agents acquired during birthprocess are herpes simplex virus and cytomegalovirus. C. trachomatisis also acquired during delivery and usually presents at 2–8wks of age with staccato cough and wheezing. History of conjunctivalinfection may or may not exist.

Inadequate hand washing and exposureto respiratory equipment or humidified incubators may contributeto infection, especially with S. aureus and gram-negative entericbacteria.

Other causes of postnatal infectionsinclude respiratory syncytial virus, parainfluenza viruses, influenzaviruses, herpes simplex virus, cytomegalovirus, and fungi (C. albicans).

Infants with pneumonia present withrespiratory distress. Chest radiography shows interstitial or alveolarinfiltrates or consolidation. With suspected bacterial pneumoniain newborns, blood and spinal fluid cultures should be performed,and treatment begun immediately while awaiting culture results.

Diagnosis of viral infections is discussedin other chapters.

Pulmonary Air Leaks

Extrapulmonaryair can accumulate in interstitial spaces of lung (pulmonary interstitialemphysema), mediastinum (pneumomediastinum), pleural space (pneumothorax),and pericardium (pneumopericardium).

Common cause of pulmonary interstitial emphysemais positive-pressure mechanical ventilation.

Pneumomediastinum results from dissectionof air from interstitial space into mediastinum.

Pneumothorax results from mediastinalair rupture into pleural space or rupture of air blebs on surfaceof lung. Most common causes of pneumothorax are respiratory distresssyndrome, meconium aspiration, and high-pressure mechanical ventilation.

Pneumopericardium is produced fromdissection of mediastinal air into pericardium.

Clinical presentation depends on sizeand location of air leak. Significant unilateral pneumothorax collapsesipsilateral lung and shifts heart and mediastinum to opposite sidewith diminished breath sounds on affected side. Significant pneumopericardiummay compromise cardiac filling and cause diminished cardiac output.

Chest radiography is diagnostic ofdifferent types of air leak.

Pulmonary Hemorrhage

Predisposingfactors in neonatal period include perinatal asphyxia, septicemia,and mechanical ventilation, especially in those with respiratorydistress syndrome.

Accompanying respiratory distress isbloody fluid, which oozes from nose, mouth, or endotracheal tube.

Depending on how severe bleeding is,chest radiography may show spectrum of findings ranging from patchyinfiltrates to opacification of lungs.

Bronchopulmonary Dysplasia

This form of chronic lung disease developsin neonates treated with prolonged oxygen therapy and positive-pressureventilation for primary lung disorders. Most infants improve duringfirst 1–2 yrs of life, and with time chest radiograph becomesnormal. However, some of these children continue to have abnormalpulmonary function in childhood. Others with severe disease developcor pulmonale and succumb to their illness.

Congenital Malformations of Lungs, Bronchi, Diaphragm, andRib Cage

Lung Agenesis and Aplasia

Lung agenesisis complete absence of lung or lobe and its branches, whereas lung aplasiais complete absence of lung tissue except for presence of smalllobar bronchus.

Respiratory distress often occurs atbirth with decreased breath sounds on affected side.

Chest radiography shows opaque hemithoraxwith displacement of mediastinum and normal lung toward involvedside.

Bronchoscopy shows absence of mainbronchus in agenesis and presence of small bronchus in aplasia.

Pulmonary Hypoplasia

Pulmonaryhypoplasia refers to smaller than normal lungs. Can be isolatedmalformation or occur in association with space-occupying lesionsof thorax (congenital diaphragmatic hernia, cystic adenomatoid malformation,large pleural effusion), oligohydramnios (renal agenesis, polycystickidney disease), and thoracic and abdominal wall abnormalities (asphyxiatingthoracic dystrophy, large omphalocele).

Respiratory distress, chronic cough,and recurrent infection may occur with unilateral hypoplasia. Thoraxis asymmetric because of underdevelopment of 1 side.

Chest radiography shows small hemithoraxwith displacement of mediastinum toward affected side. When bilateralhypoplasia occurs as isolated malformation, respiratory distressoccurs at birth and chest radiography shows small but clear lungfields.

Pulmonary Sequestration

Mass ofnonfunctioning pulmonary tissue that receives its blood supply fromsystemic circulation.

May occur within or outside a lobe.Intralobar sequestration usually occurs in lower lobe of eitherlung, whereas extralobar sequestration usually occurs just aboveor below diaphragm on left side. Whereas intralobar sequestrationis usually isolated malformation, extralobar sequestration is commonly associatedwith other malformations (e.g., diaphragmatic hernia and pulmonaryhypoplasia).

Clinical findings include respiratorydistress, hemoptysis, and recurrent pneumonia.

Chest radiography shows mass lesion.

Chest CT or MRI is usually diagnostic.

Lobar Emphysema

Overdistensionof lobe of lung (usually upper lobe). Usually congenital but alsomay be acquired secondary to extrinsic or intrinsic airway obstruction.

Respiratory distress occurs with decreasedbreath sounds and hyperresonance on involved side.

Chest radiography shows large distendedlobe or lobes with displacement of mediastinum to opposite sideand compression of contralateral lung. Extension of pulmonary vesselsto periphery of hyperexpanded lung almost always distinguishes lobaremphysema from lung cyst or pneumothorax.

Cystic Lung Lesions

Bronchogenic Cyst

Abnormalbudding or branching of tracheobronchial tree produces bronchogenic cysts,which are found incidentally or because they are infected. Locationcan be above or at carina or adjacent to 1 of main lobar bronchi.

They usually do not communicate withtracheobronchial tree and are usually fluid-filled, but if theycommunicate with airway or esophagus, they may contain air. Airwayor lung compression can cause respiratory distress.

CT or MRI is usually diagnostic.

Congenital Cystic Adenomatoid Malformation

Usuallyconsists of multiple cysts, frequently within 1 lobe of lung.

Size of lesion determines age of presentationand degree of respiratory distress.

Chest CT is usually diagnostic.

Intrapulmonary Cysts

Can be singleor multiple and involve ≥1 lobes of lung.

Respiratory distress may occur duringneonatal period. Older children may develop chronic cough or persistentinfiltrate.

Chest radiography usually shows ovalor round translucent area or areas within pulmonary parenchyma containingair or combination of fluid and air.

Chest CT usually confirms diagnosis.

Congenital Pulmonary Lymphangiectasia

Is the dilatationof lung lymphatics. Can occur as isolated defect, with congenital heartlesions that cause obstruction of pulmonary venous drainage, orwith generalized lymphangiectasia.

Respiratory distress usually beginsat birth.

Chest radiography shows reticular appearanceof lungs with nodular infiltrates and hyperinflation.

Localized form of this disorder, whichis less common, may only involve 1 or 2 lobes of lung and presentlater in life with mild respiratory distress or abnormal chest radiograph.

Lung biopsy confirms diagnosis.

Chylothorax

Presenceof chylous fluid in the thorax. Usually attributed to trauma fromdelivery or congenital abnormalities of thoracic duct system.

Lymph does not become chylous untilingestion of formula or breast milk. If large amount of chyle accumulates,respiratory distress occurs, with decreased breath sounds over affectedthorax.

Chest radiography shows large fluidcollection and shift of mediastinum.

Thoracentesis reveals chyle, whichappears milky and has high protein and fat content.

Bronchial Malformations

Bronchialstenosis usually involves main bronchus with narrowing just distalto carina. Narrowing of lobar bronchus usually results in recurrentinfection or atelectasis of involved lobe. Usual presenting featuresare respiratory distress and recurrent lung infection.

Chest radiography may show hyperinflationof involved lung and evidence of recurrent infection or atelectasis.

Chest CT or bronchoscopy is usuallydiagnostic.

Diaphragm Lesions

Congenital Diaphragmatic Hernia

Congenitaldefect in diaphragm allows herniation of abdominal organs into hemithorax,producing varying degrees of lung hypoplasia. Nearly 90% areon left side.

Severe respiratory distress beginsat birth.

Diagnostic chest radiograph shows air-filledloops of bowel and occasionally liver in thoracic cavity.

Diaphragmatic Eventration

Abnormalhigh position of diaphragm or portion of diaphragm, which is dueto congenital defect of muscularization of diaphragm.

Most children are asymptomatic, butmild respiratory distress can occur.

Diagnosis is usually made by chestradiography or fluoroscopy.

Diaphragmatic Paralysis or Paresis

Occurrenceis usually due to phrenic nerve injury from thoracic surgery.

Respiratory distress and asymmetricchest movement can occur.

Fluoroscopy or U/S that showsparadoxic movement of affected hemidiaphragm during respirationis diagnostic.

Rib Cage Anomalies

Thoracicrib cage anomalies that reduce amount of intrathoracic volume maycause respiratory distress. These include asphyxiating thoracicdystrophy, thanatophoric dysplasia, achondrogenesis, and chondroectodermaldysplasia.

Structural anomalies of rib cage andthorax usually are obvious on physical exam.

Physical exam, chest radiograph, andskeletal survey are usually diagnostic of specific disorder.

Persistent Fetal Circulation

Is the persistenceof high pulmonary vascular resistance after birth with resultinghypoxemia and cyanosis. Affected infants are usually near term,and many have history of perinatal asphyxia.

Soon after birth, respiratory distressoccurs. Hyperoxia test with exposure to 100% oxygen for5–10 mins shows small, if any, increase in partial pressureof arterial oxygen (P_aO₂)(<20 mm Hg). Simultaneous preductal-postductal measurementsof P_aO₂ inright arm and umbilical artery reveal P_aO₂ inright arm that is >15 mm Hg higher than in umbilical artery,which is consistent of right-to-left shunt across patent ductusarteriosus

2-D echocardiogram with Doppler methodsshould be performed to rule out any form of structural cardiac disease.

Cardiac Disorders

Disorders that cause cardiac failure or cyanosismay produce respiratory distress. See Chap.7, Cardiac Failure, and Chap. 12, Cyanosis.

Hematologic Disorders

Anemia

Severe acute or chronic anemia may causerespiratory distress. Pallor usually is evident. Low Hct or Hgbconfirms presence of anemia. Diagnostic approach to anemia is discussedin Chap. 45, Pallor (Anemia).

Polycythemia

Common occurrence in infants who have haddelayed clamping of umbilical cord or in infants of diabetic mothers.Venous Hct is greater than 65%, and mild respiratory distressmay occur.

Metabolic Disorders

Hypothermia

May occur in preterm low-birth-weight infantswho are otherwise normal, or in ill newborns who have bacterialmeningitis, septicemia, or intracranial hemorrhage. Oxygen consumptionis significantly increased, and hypoxemia as well as metabolic acidosismay occur.

Hypoglycemia

Irregularrespirations, apnea, seizures, and alteration of consciousness mayoccur in infants with hypoglycemia.

Low blood glucose is diagnostic (see Chap. 59, Seizures).

Metabolic Acidosis

Increase in minute ventilation is compensatoryresponse to metabolic acidosis and lowered blood pH. Normal aniongap with reduced bicarbonate may occur with diarrhea or renal tubularacidosis. Increased anion gap with accumulation of fixed acid occurswith lactic acidosis (lactate), diabetic ketoacidosis (beta-hydroxybutyrate,acetoacetate), and organic acidemias (organic acids).

Neurologic and Muscle Disorders

Brain Disorders

Respiratory distress and apnea may occurwith intracranial hemorrhage or cerebral edema as consequence ofperinatal asphyxia or birth trauma. Other causes of depressed respirationand apnea include cerebral malformations (Chiari, Dandy-Walker),bacterial meningitis, viral encephalitis, and brain tumors.

Spinal Cord Injury

Injury tospinal cord in neonates may occur with vaginal breech delivery orshoulder dystocia.

Fractures of vertebrae with transectionof the cord may result in irregular respirations and apnea, as wellas absence of spontaneous movements.

Neurologic findings depend on locationand severity of lesion.

Neuromuscular Disorders

Disorders affecting neuromuscular system(spinal muscular atrophy, myasthenia gravis, congenital myopathies)may produce slow and shallow respirations with hypoventilation andrespiratory failure (see Chap.33, Hypotonia and Weakness).

Drugs

Drugs (e.g., magnesium sulfate, morphine,and meperidine) that are given to some mothers during labor cancause neonatal respiratory depression. Neonatal drug withdrawalsyndrome may produce tachypnea as 1 of its manifestations. >>

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Source: The Diagnostic Approach to Symptoms and Signs in Pediatrics, 2006

Cough, barking: History and physical examination
(Nursing: Interpreting Signs and Symptoms)

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Source: Nursing: Interpreting Signs and Symptoms, 2007

Cough, nonproductive: History and physical examination
(Nursing: Interpreting Signs and Symptoms)

Ask the patient when his cough began and whether body position, the time of day, or a specific activity affects it. How does the cough sound—harsh, brassy, dry, or hacking? Try to determine if the cough is related to smoking or a chemical irritant. If the patient smokes or has smoked, note the number of packs smoked daily multiplied by years (“pack-years”). Next, ask about the frequency and intensity of the coughing. If he has pain associated with coughing, breathing, or activity, when did it begin? Where is it located?

Ask the patient about recent illness (especially a cardiovascular or pulmonary disorder), surgery, or trauma. Also ask about hypersensitivity to drugs, foods, pets, dust, or pollen. Find out which medications the patient takes, if any, and ask about recent changes in schedule or dosages. Ask about recent changes in his appetite, weight, exercise tolerance, or energy level and recent exposure to irritating fumes, chemicals, or smoke.

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Source: Nursing: Interpreting Signs and Symptoms, 2007

Cough, productive: History and physical examination
(Nursing: Interpreting Signs and Symptoms)

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Source: Nursing: Interpreting Signs and Symptoms, 2007

Fever [Pyrexia]: History and physical examination
(Nursing: Interpreting Signs and Symptoms)

If the patient's fever is only mild to moderate, ask him when it began and how high his temperature reached. Did the fever disappear, only to reappear later? Did he experience other symptoms, such as chills, fatigue, or pain?

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Source: Nursing: Interpreting Signs and Symptoms, 2007

COUGH: Approach to the Diagnosis
(Differential Diagnosis in Primary Care)

Clinically, exposure to dust, smoke, and various gases should be looked for in the patient presenting with a cough. Postnasal drip from chronic sinusitis should be ruled out. An allergic history (e.g., hay fever) is important. Cardiovascular disease should be carefully excluded, especially when sputum is negative for routine cultures, tuberculosis, fungi, and Papanicolaou smears and chest x-rays, bronchoscopy, and bronchography are normal. Hysterical cough should be considered, however, as well as reflux esophagitis and hiatal hernia. A sputum and nasal smear for eosinophils should be done to rule out asthma. A trial of therapy may be indicated.

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Source: Differential Diagnosis in Primary Care, 2007

FEVER: Approach to the Diagnosis
(Differential Diagnosis in Primary Care)

There are certain things to remember when a patient with fever is approached. First, a mild elevation up to 100.5^∘F (38^∘C) rectally may be normal in some people. Second, one should rule out malingering by the patient or incorrect recording by hospital personnel. Finally, psychogenic disorders must be ruled out. The duration and severity of the fever are important. If possible, a careful chart of the fever should be made with the patient off all drugs (especially aspirin and steroids). Conditions with intermittent or relapsing fever such as brucellosis, malaria, and Mediterranean fever will be elucidated in this fashion (see Table 28). The association with other symptoms is important. Fever, right upper quadrant pain, and jaundice suggest cholecystitis or cholangitis, whereas fever with right-sided flank pain suggests pyelonephritis. After taking a few moments to jot down the differential before launching into the history and physical examination, one can question and examine the patient more appropriately. The differential diagnosis will also lead to more appropriate use of laboratory testing.

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Source: Differential Diagnosis in Primary Care, 2007

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TREATMENTS & RESEARCH

Dr. Huntley's Diagnosis Checklist

Diagnosis of Respiratory syncytial virus

Respiratory syncytial virus Diagnosis: Book Excerpts

Tests and diagnosis discussion for Respiratory syncytial virus:

Diagnostic Tests for Respiratory syncytial virus: Online Medical Books

COUGH: Ask the following questions: (Algorithmic Diagnosis of Symptoms and Signs)

DIAGNOSTIC WORKUP

FEVER, ACUTE: Ask the Following Questions: (Algorithmic Diagnosis of Symptoms and Signs)

DIAGNOSTIC WORKUP

FEVER, CHRONIC: Ask the Following Questions: (Algorithmic Diagnosis of Symptoms and Signs)

DIAGNOSTIC WORKUP

Fever: Differential Diagnosis (In a Page: Signs and Symptoms)

Workup and Diagnosis

Cough - Nonproductive: Differential Diagnosis (In a Page: Signs and Symptoms)

Workup and Diagnosis

Cough - Productive: Differential Diagnosis (In a Page: Signs and Symptoms)

Workup and Diagnosis

Rash with Fever: Differential Diagnosis (In a Page: Signs and Symptoms)

Workup and Diagnosis

Fever – Cyclic: Differential Diagnosis (In A Page: Pediatric Signs and Symptoms)

Workup and Diagnosis

Fever – Recurrent: Differential Diagnosis (In A Page: Pediatric Signs and Symptoms)

Workup and Diagnosis

Fever – Unknown Origin: Differential Diagnosis (In A Page: Pediatric Signs and Symptoms)

Workup and Diagnosis

Cough – Acute: Differential Diagnosis (In A Page: Pediatric Signs and Symptoms)

Workup and Diagnosis

Cough – Chronic: Differential Diagnosis (In A Page: Pediatric Signs and Symptoms)

Workup and Diagnosis

Fever – Acute: Differential Diagnosis (In A Page: Pediatric Signs and Symptoms)

Workup and Diagnosis

COUGH: Approach to the Diagnosis (Differential Diagnosis in Primary Care)

FEVER: Approach to the Diagnosis (Differential Diagnosis in Primary Care)

Fever: History and physical examination (Handbook of Signs & Symptoms (Third Edition))

Cough, barking: History and physical examination (Handbook of Signs & Symptoms (Third Edition))

Cough, nonproductive: History and physical examination (Handbook of Signs & Symptoms (Third Edition))

Cough, productive: History and physical examination (Handbook of Signs & Symptoms (Third Edition))

Respiratory syncytial virus infection: Diagnosis (Professional Guide to Diseases (Eighth Edition))

Acute respiratory failure in COPD: Diagnosis (Professional Guide to Diseases (Eighth Edition))

Infant respiratory distress syndrome: Diagnosis (Professional Guide to Diseases (Eighth Edition))

Colorado tick fever: Diagnosis (Professional Guide to Diseases (Eighth Edition))

Lassa fever: Diagnosis (Professional Guide to Diseases (Eighth Edition))

Relapsing fever: Diagnosis (Professional Guide to Diseases (Eighth Edition))

Rheumatic fever and rheumatic heart disease: Diagnosis (Professional Guide to Diseases (Eighth Edition))

Rocky Mountain spotted fever: Diagnosis (Professional Guide to Diseases (Eighth Edition))

Whooping cough: Diagnosis (Professional Guide to Diseases (Eighth Edition))

Introduction: Respiratory Disorders: Diagnostic tests (Professional Guide to Diseases (Eighth Edition))

Severe acute respiratory syndrome: Diagnosis (Professional Guide to Diseases (Eighth Edition))

Cough, barking: History and physical examination (Professional Guide to Signs & Symptoms (Fifth Edition))

Cough, nonproductive: History and physical examination (Professional Guide to Signs & Symptoms (Fifth Edition))

Cough, productive: History and physical examination (Professional Guide to Signs & Symptoms (Fifth Edition))

Fever [Pyrexia]: History and physical examination (Professional Guide to Signs & Symptoms (Fifth Edition))

Cough: History (The 10-Minute Diagnosis Manual: Symptoms and Signs in the Time-Limited Encounter)

Physical examination

Fever: History (The 10-Minute Diagnosis Manual: Symptoms and Signs in the Time-Limited Encounter)

Physical examination

Rash Accompanied by Fever: History (The 10-Minute Diagnosis Manual: Symptoms and Signs in the Time-Limited Encounter)

Physical examination

Fever of Unknown Origin: Differential Overview (Field Guide to Bedside Diagnosis)

Diagnostic Approach

Acute Cough: Differential Overview (Field Guide to Bedside Diagnosis)

Diagnostic Approach

Chronic Cough: Differential Overview (Field Guide to Bedside Diagnosis)

Diagnostic Approach

Respiratory syncytial virus infection: Diagnosis (Handbook of Diseases)

Acute respiratory failure in COPD: Diagnosis (Handbook of Diseases)

Rheumatic fever and rheumatic heart disease: Diagnosis (Handbook of Diseases)

Respiratory alkalosis: Diagnosis (Handbook of Diseases)

Respiratory distress syndrome: Diagnosis (Handbook of Diseases)

Respiratory acidosis: Diagnosis (Handbook of Diseases)

Fever: History (Alarming Signs and Symptoms: Lippincott Manual of Nursing Practice Series)

Physical examination

Cough, barking: History (Alarming Signs and Symptoms: Lippincott Manual of Nursing Practice Series)

Physical examination

Cough, productive: History (Alarming Signs and Symptoms: Lippincott Manual of Nursing Practice Series)

Physical examination

Fever: History (Signs & Symptoms: A 2-in-1 Reference for Nurses)

Cough, barking: History (Signs & Symptoms: A 2-in-1 Reference for Nurses)

Cough, nonproductive: History (Signs & Symptoms: A 2-in-1 Reference for Nurses)

TREATMENTS &
RESEARCH

Dr. Huntley's
Diagnosis
Checklist

COUGH: Ask the following questions:
(Algorithmic Diagnosis of Symptoms and Signs)

FEVER, ACUTE: Ask the Following Questions:
(Algorithmic Diagnosis of Symptoms and Signs)

FEVER, CHRONIC: Ask the Following Questions:
(Algorithmic Diagnosis of Symptoms and Signs)

Fever: Differential Diagnosis
(In a Page: Signs and Symptoms)

Cough - Nonproductive: Differential Diagnosis
(In a Page: Signs and Symptoms)

Cough - Productive: Differential Diagnosis
(In a Page: Signs and Symptoms)

Rash with Fever: Differential Diagnosis
(In a Page: Signs and Symptoms)

Fever – Cyclic: Differential Diagnosis
(In A Page: Pediatric Signs and Symptoms)

Fever – Recurrent: Differential Diagnosis
(In A Page: Pediatric Signs and Symptoms)

Fever – Unknown Origin: Differential Diagnosis
(In A Page: Pediatric Signs and Symptoms)

Cough – Acute: Differential Diagnosis
(In A Page: Pediatric Signs and Symptoms)

Cough – Chronic: Differential Diagnosis
(In A Page: Pediatric Signs and Symptoms)

Fever – Acute: Differential Diagnosis
(In A Page: Pediatric Signs and Symptoms)

COUGH: Approach to the Diagnosis
(Differential Diagnosis in Primary Care)

FEVER: Approach to the Diagnosis
(Differential Diagnosis in Primary Care)

Fever: History and physical examination
(Handbook of Signs & Symptoms (Third Edition))

Cough, barking: History and physical examination
(Handbook of Signs & Symptoms (Third Edition))

Cough, nonproductive: History and physical examination
(Handbook of Signs & Symptoms (Third Edition))

Cough, productive: History and physical examination
(Handbook of Signs & Symptoms (Third Edition))

Respiratory syncytial virus infection: Diagnosis
(Professional Guide to Diseases (Eighth Edition))

Acute respiratory failure in COPD: Diagnosis
(Professional Guide to Diseases (Eighth Edition))

Infant respiratory distress syndrome: Diagnosis
(Professional Guide to Diseases (Eighth Edition))

Colorado tick fever: Diagnosis
(Professional Guide to Diseases (Eighth Edition))

Lassa fever: Diagnosis
(Professional Guide to Diseases (Eighth Edition))

Relapsing fever: Diagnosis
(Professional Guide to Diseases (Eighth Edition))

Rheumatic fever and rheumatic heart disease: Diagnosis
(Professional Guide to Diseases (Eighth Edition))

Rocky Mountain spotted fever: Diagnosis
(Professional Guide to Diseases (Eighth Edition))

Whooping cough: Diagnosis
(Professional Guide to Diseases (Eighth Edition))

Introduction: Respiratory Disorders: Diagnostic tests
(Professional Guide to Diseases (Eighth Edition))

Severe acute respiratory syndrome: Diagnosis
(Professional Guide to Diseases (Eighth Edition))

Cough, barking: History and physical examination
(Professional Guide to Signs & Symptoms (Fifth Edition))

Cough, nonproductive: History and physical examination
(Professional Guide to Signs & Symptoms (Fifth Edition))

Cough, productive: History and physical examination
(Professional Guide to Signs & Symptoms (Fifth Edition))

Fever [Pyrexia]: History and physical examination
(Professional Guide to Signs & Symptoms (Fifth Edition))

Cough: History
(The 10-Minute Diagnosis Manual: Symptoms and Signs in the Time-Limited Encounter)

Fever: History
(The 10-Minute Diagnosis Manual: Symptoms and Signs in the Time-Limited Encounter)

Rash Accompanied by Fever: History
(The 10-Minute Diagnosis Manual: Symptoms and Signs in the Time-Limited Encounter)

Fever of Unknown Origin: Differential Overview
(Field Guide to Bedside Diagnosis)

Acute Cough: Differential Overview
(Field Guide to Bedside Diagnosis)

Chronic Cough: Differential Overview
(Field Guide to Bedside Diagnosis)

Respiratory syncytial virus infection: Diagnosis
(Handbook of Diseases)

Acute respiratory failure in COPD: Diagnosis
(Handbook of Diseases)

Rheumatic fever and rheumatic heart disease: Diagnosis
(Handbook of Diseases)

Respiratory alkalosis: Diagnosis
(Handbook of Diseases)

Respiratory distress syndrome: Diagnosis
(Handbook of Diseases)

Respiratory acidosis: Diagnosis
(Handbook of Diseases)

Fever: History
(Alarming Signs and Symptoms: Lippincott Manual of Nursing Practice Series)

Cough, barking: History
(Alarming Signs and Symptoms: Lippincott Manual of Nursing Practice Series)

Cough, productive: History
(Alarming Signs and Symptoms: Lippincott Manual of Nursing Practice Series)

Fever: History
(Signs & Symptoms: A 2-in-1 Reference for Nurses)

Cough, barking: History
(Signs & Symptoms: A 2-in-1 Reference for Nurses)

Cough, nonproductive: History
(Signs & Symptoms: A 2-in-1 Reference for Nurses)

Cough, productive: History
(Signs & Symptoms: A 2-in-1 Reference for Nurses)

Cough: Clinical Features and Diagnosis
(The Diagnostic Approach to Symptoms and Signs in Pediatrics)

Fever: Clinical Features and Diagnosis: Acute Fever
(The Diagnostic Approach to Symptoms and Signs in Pediatrics)