CD40LG and coccidioidomycosis: Serological testing methods for confirmation of coccidioidal infection include enzyme immunoassays (EIA), often used to screen for coccidioidomycosis in high volume settings, immunodiffusion, which can detect both IgG and IgM antibodies despite its sensitivity varying with serum concentration, and complement fixation (CF) testing, which detects IgG antibodies to the chitinase antigen [41,79].