Abstract
Coccidioidomycosis is a common cause of community-acquired pneumonia in areas of the southwestern United States in which the disease is endemic. Clinical presentations range from self-limited disease to severe disseminated disease. Therefore, early and accurate diagnosis is essential to ensure appropriate treatment and monitoring. Currently available diagnostic tests have variable accuracy, particularly in certain patient populations, and new tests may offer improved accuracy for the diagnosis of coccidioidomycosis. Serum samples from 103 cases of coccidioidomycosis and 373 controls were tested for IgG and IgM antibodies using the MVista anti-Coccidioides antibody enzyme immunoassay. Serum specimens from 170 controls from areas in which the disease is endemic and 44 cases were tested by immunodiffusion at MiraVista Diagnostics. The sensitivity of the MVista antibody assay was 88.3%, and the specificity was 90%. The sensitivity was maintained in the presence of immunocompromising conditions or immunosuppressive therapies. The sensitivity of immunodiffusion was 60.2%, and the specificity was 98.8%. The sensitivity of complement fixation (62 cases) was 66.1%, but the specificity could not be determined. The MVista anti-Coccidioides antibody enzyme immunoassay offers improved sensitivity, compared with immunodiffusion and complement fixation, is not impaired in immunocompromised patients, and permits highly reproducible semiquantification.