Coccidioidomycosis is an infection caused by inhalation of spores of Coccidioides immitis, a fungus found in the soil in certain parts of the southwestern U.S., Mexico, and Central and South America.
Causes, incidence, and risk factors
Coccidioides infection begins in the lungs, following inhalation of the spores. About 60% of infections resolve without ever causing symptoms and are only recognized by a positive coccidioidin skin test.
In the remaining 40% of infections, symptoms range from mild (cold-like or flu-like) to severe (pneumonia). (See coccidioidomycosis.) In less than 1% of infections, widespread disease occurs when the fungus spreads from the lungs through the blood stream to involve the skin, bones, joints, lymph nodes, and central nervous system or other organs.
Individuals of African or Philippine descent, and people with weakened immune systems due to AIDS, diabetes, or immunosuppressive medications, may develop more serious infections. Occasionally the acute infection may develop into a chronic pulmonary (lung) disease or can reactivate after a long latent period.
A history of travel to an endemic region is the key to suspecting coccidioidal infection. Arizona, California (especially San Joaquin Valley), and - to a lesser extent - western Texas, are endemic regions in the USA.
- Sputum or phlegm
- Chest pain, varies from mild sense of constriction to severe
- Night sweats
- Muscle stiffness
- Muscle aches
- Joint stiffness
- Rash, may be painful, red, on lower legs (erythema nodosum)
- Weight loss
- Lymph node swelling
Signs and tests
- Sputum smear (KOH test or Papanicolaou stain)
- Bronchoscopy with lavage
- Biopsy of lymph node or lung (often done with bronchoscopy)
The acute disease is almost always benign and goes away without treatment. Bedrest and treatment of flu-like symptoms until fever disappears may be recommended.
In severe forms of the disease (disseminated coccidioidomycosis), antifungal treatment with amphotericin B, fluconazole, or itraconazole can be used. The best length of treatment with these medications has not been determined for this disease.
The outlook in milder cases is usually good. Disseminated coccidioidomycosis can be serious, particularly in people with weakened immune systems.
- Chronic pulmonary coccidioidomycosis
- Disseminated coccidioidomycosis
Calling your health care provider
- Symptoms develop that suggest coccidioidomycosis
- Symptoms worsen or do not improve with treatment
- New symptoms develop
Avoiding travel to regions where this fungus is found may prevent risk of developing this disorder. However, this is not practical or possible for many people. It may be prudent to try to avoid contact with soil in these regions if you have a weakened immune system due to HIV or other conditions.
by Potos A. Aagen, M.D.
All ArmMed Media material is provided for information only and is neither advice nor a substitute for proper medical care. Consult a qualified healthcare professional who understands your particular history for individual concerns.