Coccidioides immitis Antibodies, IgG and IgM, EIA

Use: Qualitative detection of antibodies against the fungus Coccidioides to aid in the diagnosis of Coccidioidomycosis (Valley Fever). Specimens positive for Coccidioides antibody by EIA should be confirmed by additional testing (complement fixation and immunodiffusion). Coccidioides live in the dust and soil in some areas of the southwestern United States, Mexico, and South America. In the U.S., Coccidioides live in Arizona, California, Nevada, New Mexico, Texas, and Utah. Many people who are exposed to Coccidioides never develop symptoms. In symptomatic individuals (Valley Fever), symptoms may appear between 1 to 3 weeks after they breathe in fungal spores and usually last for a few weeks to months. Approximately 5% to 10% of people who get Valley Fever will develop serious or long-term problems of the lungs. In approximately 1% of people the infection spreads from the lungs to other parts of the body, such as the central nervous system, skin, or bones and joints. The IgM antibody response (early infection) is measured against the tube precipitin (TP) antigen, and IgG antibody response (late infection) is measured against complement fixation (CF) antigen.

Limitations: Specimens positive for Coccidioides antibody by EIA should be confirmed by additional testing (complement fixation and immunodiffusion). A negative result with both IgM and IgG does not preclude diagnosis of coccidioidomycosis. False-positive due to cross-reactivity has been observed in individuals with other fungal diseases. Diagnosis of coccidioidomycosis should be based on laboratory and clinical findings.

Methodology: EIA