Coccidioidomycosis - chronic pulmonary

Definition

Chronic pulmonary coccidioidomycosis is a lung infection caused by breathing in the fungus coccidioides. This fungus is found in the soil in certain parts of the southwestern U.S., Mexico, and Central and South America.

Causes

The infection is caused by breathing in the spores of a fungus found in desert regions such as Arizona or California's San Joaquin Valley. The disease can have an acute, chronic, or disseminated form.

The chronic form usually develops after a period of months to years following a harmless infection that may have gone undiagnosed. Lung abscesses may form and may rupture into the pleural spaces causing empyema (pus in the pleural space) or bronchopleural fistula. Scarring (fibrosis) and cavities may gradually form in the upper lungs as the chronic form of coccidioidomycosis slowly progresses over months to years.

Still, the majority of pulmonary coccidioidomycosis infections do not become chronic. In fact, the majority of infections cause no symptoms and are only recognized by a positive coccidioidin skin test.

Dark-skinned people and people with a weak immune system are more susceptible to infection and more likely to form chronic or disseminated (spreading to other organs) forms of the disease.

Symptoms

• Chronic cough
• Blood-tinged sputum
• Loss of appetite
• Weight loss
• Fever
• Shortness of breath

Additional symptoms that may be associated with this disease:

• Wheezing
• Sweating, excessive
• Joint stiffness
• Chest pain
• Headache

Exams and Tests

• Sputum smear (KOH test)
• Sputum fungal culture
• Serum coccidioides complement fixation titer (serology)
• CBC with differential
• Chest x-ray
• Chest CT scan
• Coccidioidin or spherulin skin test
• Bronchoscopy
• Bronchoscopy with transbronchial biopsy
• Open lung biopsy
• Mediastinoscopy
• Lumbar puncture (spinal tap) to exclude meningitis involvement

Treatment

Antifungal medications are prescribed to treat the infection. The intravenous antibiotic, amphotericin B, is used for severe forms of disease. Itraconazole and fluconazole are oral antibiotic options with activity against this fungus. Ketoconazole is another option, but appears less effective. Treating any underlying immunocompromised state (such as AIDS) and minimizing immunosuppressant medications (such as steroids or chemotherapy) is also crucial if the patient's immune system is to properly fight the coccidioidomycosis fungal infection.

Outlook (Prognosis)

With treatment the outcome is usually good, although relapses may occur. Some patients, such as those who are immunocompromised (from AIDS or immunosuppressing drugs) may need life-long anti-fungal medication to prevent relapse.

Possible Complications

• Pleural effusion
• Relapse of infection
• Disseminated coccidioidomycosis
• Coccidioidomycosis meningitis
• Arthritis
• Rash
• Empyema
• Bronchopleural fistula
• Lung scarring (fibrosis)
• Lung cavities

When to Contact a Medical Professional

Call for an appointment with your health care provider if coccidioidomycosis symptoms worsen or do not improve with treatment.

Call your health care provider if new symptoms develop.

Prevention

Because coccidioidomycosis usually causes no symptoms -- or, in the majority of symptomatic infections, it usually resolves quickly on its own without causing significant symptoms -- there is generally no need to avoid infection. Immunocompromised people (such as AIDS patients and those on immunosuppressing drugs) may avoid travel to regions where this fungus is found, if they wish to minimize any risk of developing this rare, chronic disorder.

Chiller TM. Coccidioidomycosis. Infect Dis Clin North Am. 2003; 17(1): 41-57, viii.

Murray J, Nadel J. Textbook of Respiratory Medicine. 3rd ed. Philadelphia, Pa: WB Saunders; 2000.

Mandell GL, Bennett JE, Dolin R. Principles and Practice of Infectious Diseases. 5th ed. London, UK: Churchill Livingstone; 2000:2746-2755.

Galgiani JN, Ampel N, Blair JE, et al. Coccidioidomycosis. Clin Infect Dis. 2005;41:1217-23.

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