Diseases » Coccidioidomycosis

Coccidioidomycosis

Coccidioidomycosis: Excerpt from The 5-Minute Pediatric Consult

Theoklis Zaoutis, MD

Samir S. Shah, MD, MSCE

Coccidioidomycosis - BASICS

Coccidioidomycosis - description

Coccidioidomycosis is an infection caused by the dimorphic fungus Coccidioides immitis.

Coccidioidomycosis - general prevention

Infection control:

• No special isolation or precautions for the hospitalized patient
• Contaminated dressings from skin lesions should be handled and discarded with care.
• Preventive efforts are aimed at dust control and trials to eliminate organisms from soil.
• Avoidance of field activities or travel in highly endemic areas is recommended for children with a negative skin test.

Coccidioidomycosis - epidemiology

• Primary infection is most commonly seen in the summer and fall months.
• The average incubation period is 10–16 days (range 1–4 weeks).
• There is no person-to-person spread.
• 60% of acute infections are subclinical (asymptomatic).

Coccidioidomycosis - prevalence

Coccidioides immitis is found in the soil and is endemic in the southwestern US (western Texas, New Mexico, Arizona, California), northern Mexico, and parts of South and Central America. Up to 1/3 of the population in endemic areas has been infected.

Coccidioidomycosis - pathophysiology

• Inhalation of arthrospores from disturbed, arid soil is the major route of infection.
• Primary cutaneous coccidioidomycosis occurs by direct inoculation of the skin (trauma). A relatively painless, indurated nodule with occasional central ulceration develops at the site of injury. Regional lymphadenopathy is often present.
• Extrapulmonary dissemination is rare and usually involves the skin, skeletal system, and central nervous system.
• Secondary cutaneous coccidioidomycosis occurs by hematogenous spread to the skin. Lesions range from superficial maculopapular lesions to verrucous ulcers. Lesions can occur anywhere, but are most common along the nasolabial fold.
• Most patients have infection limited to a localized area of lung and hilar nodes after mounting an intense inflammatory response with granuloma formation.
• Dissemination occurs in a minority of patients via lymphatic or hematologic spread.
• The course of illness is highly variable and dependent on host immune response and amount of exposure. HIV-infected patients and other patients with immunosuppression owing to T-lymphocyte dysfunction (lymphoma, organ transplantation) are particularly susceptible to severe forms of pulmonary and extrapulmonary coccidioidomycosis.

Coccidioidomycosis - etiology

• Osteomyelitis is subacute or chronic and frequently involves more than 1 bone (40%). Common sites are the hands, feet, ribs, and vertebrae.
• Meningitis develops within 6 months of initial infection. Hydrocephalus is a common complication. CNS vasculitis and intracerebral abscesses are rare.

Coccidioidomycosis - DIAGNOSIS

Coccidioidomycosis - signs & symptoms

Coccidioidomycosis - history

• Travel or residence in an endemic area is typical. Risk factors for disseminated infection should be sought.
• Fever, dry or productive cough, and pleuritic chest pain suggest pulmonary infection.
• Hemoptysis, although rare in children, is reported in 15% of adults with symptomatic pulmonary infection.
• Trauma precedes primary cutaneous disease.
• Myalgias, arthralgias, chills, night sweats, and anorexia suggest systemic dissemination.
• Headache, vomiting, and altered mental status suggest meningitis.
• Most infections (60%) are asymptomatic.

Coccidioidomycosis - physical exam

• Signs of pneumonia and pleural effusions are often present with symptomatic pulmonary infection.
• Indurated nodules and regional lymphadenopathy are seen with primary cutaneous infection.
• Erythematous maculopapular rash suggests secondary cutaneous involvement and is seen in 50% of symptomatic children. It is usually limited to the lower trunk and thighs, but may be diffuse.
• Erythema nodosum occurs later in the course of infection. Erythema nodosum correlates with the development of cell-mediated immunity and is associated with a low incidence of dissemination.
• Chorioretinal lesions are present in ≤40% of patients with disseminated disease.
• Stridor is present with infection of the subglottic tissues.
• Signs of increased intracranial pressure are seen with central nervous system infection. Classic signs of meningeal irritation are usually absent.
• Primary pulmonary infection is usually asymptomatic.
• Symptomatic pulmonary infection is characterized by cough, chest pain, and fever. Rash, myalgias, and arthralgias may be present. Chronic pulmonary lesions are rare in children (see: “Complications”).

• Skin test in disseminated disease may be negative.
• Clinicians in endemic areas should maintain a high level of clinical suspicion.
• Diagnosis in nonendemic areas may be missed owing to low clinical suspicion or missed travel history.

Coccidioidomycosis - tests

Coccidioidomycosis - lab

• Direct examination and culture:
  • Cytologic examination of bronchoalveolar fluid is diagnostic in only about 1/3 of persons and is less sensitive than culture. Visualization of large spherules is possible in stained specimens of sputum, tracheal aspirates, urine, or tissue biopsy. They are rarely seen in CSF.
  • The organisms can be detected by culture in experienced laboratories. The yield is highest from purulent material. The yield from other sources, such as pleural fluid, blood, and gastric aspirates is lower.
• Skin testing:
  • Coccidioidin or Spherulin intradermal skin test is positive (delayed type hypersensitivity; >5 mm induration) within 2 weeks of symptom onset (range 2 days to 4 weeks). Recent conversion is diagnostic; reactivity persists after infection, thereby limiting its usefulness as a diagnostic test for acute infections.
  • Skin tests are often negative in progressive or disseminated disease and in immunocompromised patients.
• Serologic studies:
  • Coccidioides immitis–specific IgM antibody is detectable in 75% of patients 1–3 weeks after symptom onset and usually is absent after 6 months. False-positive results are seen in 15% of patients with cystic fibrosis.
  • IgG is detected by the complement fixation (CF) assay from serum or CSF. It is positive in 50% of patients at 4 weeks and 83% at 3 months following symptomatic primary infection. In general, higher titers reflect more extensive infection and rising complement fixation antibody concentrations are associated with worsening disease.
  • Hematologic findings include elevated erythrocyte sedimentation rate, leukocytosis, and, eosinophilia (in 10%).
• Other studies:
  • CSF findings in meningitis include hypoglycorrhachia and pleocytosis with mononuclear cell predominance.

Coccidioidomycosis - imaging

Radiologic studies:

• Chest radiograph may reveal well-circumscribed nodules, lobar or patchy pulmonary infiltrates, pleural effusions, cavitary lesions, and hilar adenopathy.
• Radiographs of involved bones may reveal lytic lesions. Scintigraphy of bone is more sensitive for the diagnosis of osteomyelitis.

Coccidioidomycosis - differencial diagnosis

• Other pulmonary mycoses (e.g., Histoplasma capsulatum, Aspergillus fumigatus, and Blastomyces dermatitidis)
• Mycobacterium tuberculosis (lung or CSF)
• Mycoplasma pneumoniae
• Influenza and other viral infections that present as bronchopneumonia

Coccidioidomycosis - TREATMENT

Coccidioidomycosis - general measures

• Uncomplicated or minor disease is self-limited and should not be treated with antifungal therapy (>95% of cases).
• Treatment of uncomplicated respiratory infection is recommended for infants, pregnant women, and patients with continuous fever for >1 month, >10% weight loss, extensive or progressive pulmonary disease, negative skin test results, or immunodeficiency (either from human immunodeficiency virus or as a result of immunosuppressive medications). Use either oral fluconazole or itraconazole for 3–6 months.
• Surgical débridement is used for localized and persistent lesions in bone and lung.
• Diffuse pneumonia: Start therapy with amphotericin B and replace with oral fluconazole or itraconazole when clinical improvement is demonstrated. The total length of therapy should be at least 1 year, and for patients with severe immunodeficiency, oral azole therapy should be continued as secondary prophylaxis.
• Disseminated infection, nonmeningeal: Treat with oral fluconazole or itraconazole. Amphotericin B is alternative therapy, especially if lesions worsen or are at critical locations, such as the vertebral column. The duration of therapy may be longer than for those with pneumonia only.
• Meningitis: Oral fluconazole is preferred (800–1,000 mg/d). Itraconazole (400–600 mg/d) is also effective. Therapy should be continued indefinitely.
• Intrathecal amphotericin B may be useful in central nervous system infections.
• Voriconazole, a new azole agent, and caspofungin, an echinocandin class antifungal, have in vitro activity against Coccidioides immitis.

Coccidioidomycosis - FOLLOW UP

Coccidioidomycosis - prognosis

• Most infections are asymptomatic (60%) or mild (35%) and self-limited.
• Primary infection of the lungs is usually self-limited, with a course of illness lasting 1–3 weeks; complications (see above) may prolong the course.
• Dissemination is infrequent (see above for risk factors). Morbidity and mortality have improved with use of antifungal therapy, but immunocompromised patients still have a poor prognosis after the development of disseminated infection. The mortality rate is 70% in human immunodeficiency virus-infected patients with diffuse pulmonary coccidioidomycosis.
• Meningitis, untreated, is nearly always fatal within 2 years of diagnosis.

Coccidioidomycosis - complications

• Localized complications of primary pulmonary infection are infrequent and include pleural effusions and pericarditis.
• ~5% of lung infections result in residual pulmonary sequelae, usually nodules or abscess cavities. 1/3 of these cavities spontaneously resolve within 2 years. Hemoptysis and rupture of the abscess, with formation of an empyema, are potential complications in patients with unresolved cavities.
• Risk factors for disseminated coccidioidomycosis include immunosuppression, male gender, extremes of age (neonates and elderly), African or Filipino descent, and pregnancy.
• Extrapulmonary dissemination usually develops within a year after the initial infection, but may appear much later if immunity is impaired (e.g., human immunodeficiency virus infection, malignancy, immunosuppressive therapy).
• Hydrocephalus may occur with central nervous system involvement.

Coccidioidomycosis - bibliography

1. Chu JH, Feudtner C, Heydon KH, et al. Hospitalizations for endemic mycoses: A population based national sample. Clin Infect Dis. 2006;42:822–825.
2. Deresinski SC. Coccidioidomycosis: Efficacy of new agents and future prospects. Curr Opin Infect Dis. 2001;14:693–696.
3. Dosanjh A, Theodore J, Pappagianis D. Probable false positive coccidioidal serologic results in patients with cystic fibrosis. Pediatr Transplant. 1998;2:313–317.
Galgiani JN. Coccidioides immitis. In: Mandell GL, Bennett JE, Dolin R, eds. Principles and Practice of Infectious Diseases. 5th ed. New York: Churchill Livingstone; 2000:2746–2757.
4. Galgiani JN, Ampel NM, Catanzaro A, et al. Practice guidelines for the treatment of coccidioidomycosis. Clin Infect Dis. 2000;30:658–661.
5. Galgiani JN, Catanzaro A, Cloud GA, et al. Comparison of oral fluconazole and itraconazole for progressive, nonmeningeal coccidioidomycosis: A randomized, double-blind trial. Ann Intern Med. 2000;133:676–686.
6. Stevens DA. Coccidioidomycosis. N Engl J Med. 1995;332:1077–1082.

Coccidioidomycosis - CODES

Coccidioidomycosis - icd9

114.9 Coccidioidomycosis, unspecified

Coccidioidomycosis - FAQ

• Q: Do all patients with symptomatic primary respiratory infection owing to Coccidioides immitis require treatment?
• A: No, since >95% of initial pulmonary infections are self-limited, treatment is not always required. Patients with concurrent risk factors (e.g., HIV, organ transplant, or high doses of corticosteroids) or evidence of unusually severe infections should always be treated. Factors suggesting increased severity of infection include weight loss of >10%, night sweats, infiltrates involving more than half of one lung or portions of both lungs, complement fixation antibody to Coccidioides immitis >1:16, and failure to develop dermal hypersensitivity of coccidioidal antigens.
• Q: How should pregnant women with coccidioidomycosis be managed?
• A: Diagnosis of primary infection during the third trimester of pregnancy or immediately in the postpartum period should raise consideration for treatment. During pregnancy, amphotericin B is the treatment of choice because fluconazole and other azole antifungals are likely teratogenic.

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 Coccidioidomycosis

• Back to disease: Coccidioidomycosis: Introduction
• Next Book Extract About Coccidioidomycosis: Surveys relating to Coccidioidomycosis
• More Book Extracts: All Online Books for Coccidioidomycosis

More Medical Textbooks Online about Coccidioidomycosis

Review other book chapters online related to Coccidioidomycosis:

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 Coccidioidomycosis

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:

• Surveys relating to Coccidioidomycosis
• Ask Question about Coccidioidomycosis

Tools & Services:

• Bookmark this page
• Symptom Search
• Symptom Checker
• Medical Dictionary
• Give your feedback

Medical Articles:

• Disease & Treatments Search
• Misdiagnosis Center
• Full list of interesting articles

Forums & Message Boards

• Ask or answer a question at the Boards:
• I cannot get a diagnosis. Please help.
• Tell us your medical story.
• Share your misdiagnosis story.
• What is the best treatment for my condition?
• See all the Boards.

homepage | back to top

Common Health Mistakes

Choose ... Alzheimers & Dementia Asthma Child ADHD ADHD in Adults Allergy Hypertension Bipolar Breast Cancer Celiac Disease Crohns Disease Colon Cancer Contraception Diabetes Cancer Depression Erectile Disorder Cholesterol COPD GERD Heartburn/Reflux Metabolic Syndrome Migraine/Headache Multiple Sclerosis Obesity Osteoporosis Overactive Bladder Psoriasis Sexual Disorder Sleep Disorders Smoking The Pill Ulcerative Colitis All Common Mistakes

Symptom
Checker

Choose... Fever Rash Pain Headache Fatigue Cough Other symptoms

Search Specialists by State and City

Choose... GENERAL PRACTICE CARDIAC HEALTH WOMEN'S HEALTH CANCER CARE RADIOLOGY MENTAL HEALTH PATHOLOGY EAR, NOSE, THROAT MEDICINE GENETICS NEUROLOGY DIALYSIS CARE SURGERY ORTHOPEDICS/SPORTS MEDICINE CHILDREN'S HEALTH OTHER SPECIALTIES