Diagnosis of paracoccidioidomycosis by dot immunobinding assay for antibody detection using the purified and specific antigen gp43

The dot immunobinding assay, a rapid, visually read test, was adapted for serodiagnosis and follow-up of paracoccidioidomycosis (PCM). Purified gp43 antigen was tested before and after sodium metaperiodate treatment. To evaluate the assay, it was tested with sera from PCM, histoplasmosis, Jorge Lobo's disease, aspergillosis, candidiasis, and cryptococcosis patients and healthy subjects. Native gp43 gave positive results with all sera from PCM patients and weakly positive results with sera from Jorge Lobo's disease patients (31.3%). No false-positive results were obtained when periodate-treated gp43 was used as the antigen. These results indicate that the dot immunobinding test is sensitive, specific, economical, and fast for serodiagnosis and follow-up studies of PCM. Paracoccidioidomycosis (PCM), caused by Paracoccidio-ides brasiliensis, is a fungal disease that affects many indi-viduals in Latin America. Since it is not classified as a notifiable disease, the exact number of patients is unknown. Diagnosis can be obtained by direct visualization of the fungus in biologic materials, by culture, or indirectly by various serologic tests. Although there are serologic proce