Endocarditis
Endocarditis: Excerpt from The 5-Minute Pediatric Consult
Jenifer A. Glatz, MD
Endocarditis - BASICS
Endocarditis - description
Infective endocarditis (IE) is a microbial infection of the endocardium of the heart.
Endocarditis - general prevention
- Dental hygiene
- Minimal use of central lines
- Correction of the cardiovascular anomaly by surgery or interventional catheterization techniques
- Subacute bacterial endocarditis (SBE) prophylaxis regimes as per the 2007 American Heart Association recommendations. Give as a single dose 30–60 min prior to procedure:
- Oral: Amoxicillin (50 mg/kg, max 2.0 g)
- IV or IM: Ampicillin (50 mg/kg, max 2.0 g) or ceftriaxone/cefazolin (50 mg/kg, max 1.0 g)
- Oral for penicillin-allergic patients: Cephalexin, if no history of urticaria, angioedema, or anaphylaxis (50 mg/kg, max 2.0 g), Clindamycin (20 mg/kg PO/IV, max 600 mg) or azithromicin/clarithromycin (15 mg/kg PO, max 500 mg)
- IV or IM for pencillin-allergic patients: Cefazolin, ceftriaxone or clindamycin (doses as above)
- SBE prophylaxis is recommended by the AHA only for the following cardiac conditions:
- Prosthetic cardiac valve or prosthetic material used for cardiac valve repair.
- Prior history of infective endocarditis
- Unrepaired cyanotic congenital heart disease, including palliative shunts and conduits
- Congenital heart defect repaired with prosthetic material or device for the first 6 months after the procedure
- Repaired congenital heart disease with residual defect near the site of prosthetic patch or device
- Cardiac transplantation recipients with cardiac valvulopathy
- SBE prophylaxis is recommended only for the following procedures:
- Dental procedures involving manipulation of the gingival or periapical region of teeth or perforation of the oral mucosa
- Invasive respiratory tract procedures involving incision or biopsy such as tonsillectomy/adenoidectomy or abscess drainage
- Surgery involving prosthetic intravascular or intracardiac material, including heart valves
- Procedures that do not require SBE prophylaxis:
- Placement of removable prosthodontic or orthodontic appliances
- Bleeding from trauma to the lips or oral mucosa or shedding of deciduous teeth
- Routine anesthetic injections through non-infected oral mucosa tissues
- Bronchoscopy without a biopsy
- GI or GU procedures: Prophylaxis solely to prevent IE is not recommended
Endocarditis - epidemiology
Endocarditis - incidence
- Infective endocarditis is relatively uncommon. Studies have reported incidences between 1 in 1,280 and 1 in 4,500 of all pediatric hospital admissions.
- The overall incidence of endocarditis decreased with the advent of antibiotics. However, a recent increase in frequency has been associated with improved survival of patients with congenital heart disease and the more wide and often prolonged use of central vascular catheters, especially in premature infants.
Endocarditis - risk factors
- Pre-existing heart disease (congenital or acquired)
- Prior history of endocarditis
- Cardiac surgery
- Prosthetic valves or conduits
- Indwelling catheters/intravenous drug use
Endocarditis - pathophysiology
- Infective endocarditis is primarily seen in patients with pre-existing heart disease (congenital or acquired) who develop bacteremia with organisms that are likely to cause infection.
- IV drug abusers and patients with indwelling central venous catheters may develop endocarditis even in the absence of prior heart disease.
- Local turbulence secondary to the cardiovascular abnormality is thought to result in damage of the endocardial surface. The development of a fibrin and platelet network occurs in which bacteria may then become entrapped, causing infection.
- Bacteremia may be a complication of focal infection (e.g., pneumonia, cellulitis, or UTI) or may be associated with various dental and surgical procedures. Bacteremia, however, also occurs spontaneously with usual activities, such as chewing, flossing, and brushing teeth.
- Peripheral manifestations in chronic endocarditis are mediated by immune complex reactions.
Endocarditis - etiology
- Gram-positive cocci account for 90% of culture-positive endocarditis. There has been a recent shift in the microbial etiology, corresponding with a more acute presentation
- Staphylococcus aureus is now responsible for most cases of infective endocarditis in all age groups.
- α-hemolytic streptococci (Streptococcus viridans) are the 2nd most common pathogen in children over age 1 year.
- Other organisms that can cause endocarditis are coagulase-negative staphylococci, β-hemolytic streptococci, enterococci, the HACEK group (Haemophilus aphrophilus, Haemophilus paraphrophilus, Haemophilus parainfluenzae, Actinobacillus actinomycetemcomitans, Cardiobacterium hominis, Eikenella corrodens, Kingella species), Candida species, Aspergillus species, Pseudomonas species, pneumococci, and Neisseria species.
- ~5% of endocarditis cases are reported as culture negative.
Endocarditis - DIAGNOSIS
Endocarditis - signs & symptoms
The Modified Duke Criteria define diagnostic categories (definite endocarditis, possible endocarditis, and rejected cases) based on combinations of major and minor criteria.
- Major criteria: Pathologically documented IE or organism specific high-grade bacteremia or fungemia plus definitive echocardiographic data.
- Minor criteria: Predisposing heart disease, fever, vascular/immunologic phenomena, or microbiologic evidence not within major criteria.
- Definitive endocarditis requires 2 major, or 1 major plus 3 minor, or 5 minor criteria.
- Several studies have confirmed the high sensitivity and specificity of these criteria.
Endocarditis - history
- Fever
- Malaise
- Anorexia
- Weight loss
- Heart failure symptoms
- Arthralgia/myalgia
- Neurologic symptoms
- GI symptoms
- Chest pain
- Occasionally, a recent infection, dental visit, or surgical procedure can be identified.
- Acute endocarditis is associated with a more rapidly progressive, fulminant course.
Endocarditis - physical exam
- General:
- Fever (usually low grade with α-hemolytic streptococci and high grade with S. aureus)
- Petechiae (occurring in 1/3 of cases)
- Embolic or immunologic phenomena:
- Renal: Glomerulonephritis, infarct
- Splinter hemorrhages
- Retinal hemorrhages (Roth spots)
- Osler nodes (painful)
- Janeway lesions (painless)
- Splenomegaly (occurring in about 50% of cases)
- Arthralgia/arthritis
- Neurologic: Cerebral infarction, embolism or hemorrhage. Mycotic aneurysms may also occur.
- Cardiac/Valvulitis:
- New or change in heart murmur
- Signs of CHF
- Newborns with IE may present with feeding difficulty, respiratory distress, tachycardia, hypotension, seizures, apnea and septic emboli.
Endocarditis - tests
EKG: New-onset abnormalities such as atrioventricular block (even 1st degree) may represent conduction system and myocardial involvement from invasive disease.
Endocarditis - lab
- Blood cultures:
- Most important diagnostic test for endocarditis
- Positive in 85–90% of reported cases
- Obtain 3–5 sets from different sites during the 1st 24 hours of suspected endocarditis.
- Collect the largest volume that is clinically reasonable.
- The bacteremia of endocarditis is continuous; therefore, it is not necessary to wait to obtain the blood cultures during a fever spike.
- Nonspecific data:
- Elevated erythrocyte sedimentation rate (ESR; 80%) and C-reactive protein
- Anemia (44%)
- Positive rheumatoid factor (38%)
- Hematuria (35%) and red cell casts
- Leukocytosis
- Decreased complement
Endocarditis - imaging
Echocardiography:
- Transthoracic:
- Valuable noninvasive technique in the identification of vegetations
- Specificity is 98% but sensitivity is <60%, so a negative echocardiogram does not rule out endocarditis.
- Also invaluable for follow-up, including evaluation for potential cardiac complications
- Transesophageal:
- Especially in older or obese patients, provides better visualization of smaller vegetations, with sensitivity of 76–100%.
- Recommended in patients with an inconclusive transthoracic study but a high index of suspicion for endocarditis.
- The absence of vegetation(s) by echocardiography does not rule out endocarditis.
- In patients with a prosthetic valve, echocardiography is not always helpful, as there is frequently artifact from the prosthetic valve. Abnormal movements of the valve leaflets may suggest a vegetation.
- The ESR may remain elevated for some time, even after cessation of bacteremia.
Endocarditis - differencial diagnosis
- Other infections
- Acute rheumatic fever
- Malignancy
- Connective tissue disorders
Endocarditis - TREATMENT
Endocarditis - initial stabilization
- Rest
- Antipyretics
- Optimal nutrition and hydration
- Careful dental hygiene
Endocarditis - medication
Antibiotics:
- Prolonged IV therapy (at least 4 weeks) is needed.
- Choice of antibiotic(s) and duration of treatment depend on the infecting organism, sensitivity pattern, and patient risk factors.
- For staphylococcal or fungal endocarditis, IV therapy is given for at least 6–8 weeks.
Endocarditis - surgery
Potential indications (mostly adult data):
- Severe/worsening CHF
- Valvar disease with unstable hemodynamics
- Failing medical therapy
- Large (>10 mm), mobile vegetations
- 2 or more major embolic events
- Fungal endocarditis
- Abscess formation/peri-annular extension
- Prosthetic valve endocarditis
Endocarditis - FOLLOW UP
Endocarditis - prognosis
If diagnosed in a timely fashion and appropriate therapy is instituted, prognosis is relatively good for bacterial endocarditis. Staphylococcus aureus and fungal endocarditis are associated with higher morbidity and mortality.
Endocarditis - complications
Despite improvements in diagnosis and treatment, IE continues to be a disease with significant morbidity and mortality (~10%):
- Cardiac: Valve destruction and perforation leading to incompetence, abscess, and fistula formation, heart failure, or conduction abnormalities.
- Embolic events (22–50%) may occur to multiple organ systems (CNS, bowel, coronary arteries, kidneys, spleen, skin, lungs).
Endocarditis - patient monitoring
- Obtain repeat blood cultures after a few days of antibiotic or antifungal therapy to ensure the eradication of bacteria.
- Obtain blood cultures again 2 months after completion of a full course of antibiotic therapy.
Endocarditis - bibliography
- Baddour LM, Wilson WR, Bayer AS, et al. Infective endocarditis: Diagnosis, anitmicrobial therapy and management of complications. Circulation. 2005;111:3167–3184, e394–e433.
- Ferrieri P, Gewitz MH, Gerber MA, et al. Unique features of infective endocarditis in childhood. Circulation. 2002;105:2115–2127.
Keane JF, Lock JE, Fyler DC, et al., eds. Nadas’ Pediatric Cardiology. 2nd ed. Philadelphia: Saunders Elsevier; 2006.- Milazzo AS Jr, Li JS. Bacterial endocarditis in infants and children. Pediatr Infect Dis J. 2001;20:799–801.
- Wilson W, Taubert KA, Gewitz M, et al. Prevention of infective endocarditis: Guidelines from the American Heart Association. Circulation. 2007;116:1736–1754.
Endocarditis - CODES
Endocarditis - icd9
- 421.0 Acute and subacute bacterial endocarditis
- 421.9 Acute endocarditis, unspecified
Endocarditis - FAQ
- Q: I forgot to give my child antibiotics prior to the procedure. Should I give him a dose afterward?
- A: The dosage may be administered up to 2 hr after the procedure.
- Q: My child has an innocent heart murmur. Does he need SBE prophylaxis?
- A: SBE prophylaxis is not indicated.
- Q: SBE prophylaxis is recommended for my child, but she already is on long-term antibiotic therapy with that recommended antibiotic. Should she use an additional antibiotic or increase her current dose for the procedure?
- A: An antibiotic from a different class should be selected.
>
Book Source Details
- Book Title: The 5-Minute Pediatric Consult
- Author(s): M. William Schwartz MD; et al.
- Year of Publication: 2008
- Copyright Details: The 5-Minute Pediatric Consult, Copyright © 2008 Lippincott Williams & Wilkins.
More About Endocarditis
More Medical Textbooks Online about Endocarditis
Review other book chapters online related to Endocarditis:
Medical Books Excerpts
- Myocarditis
- "Professional Guide to Diseases (Eighth Edition)" (2005)
- [ read ]
Copyright notice for book excerpts: Copyright © 2008 Lippincott Williams & Wilkins. All rights reserved.
|
|
More About This Book:
Title: The 5-Minute Pediatric Consult
Authors: M. William Schwartz MD; et al.
Publisher: Lippincott Williams & Wilkins
Copyright: 2008
ISBN: 0-7817-7577-9
|
|
» Next page: Surveys relating to Endocarditis
Rate This Website
What do you think about the features of this website?
Take our user survey and have your say:
Website User Survey
Medical Tools & Articles:
Next articles:
Tools & Services:
Medical Articles:
Forums & Message Boards
- Ask or answer a question at the Boards:
