DETECTION OF ANTIBODIES TO COCCIDIOIDES-IMMITIS BY ENZYME-IMMUNOASSAY

Two hundred twenty-six specimens (160 serum samples, 66 cerebrospinal fluid samples) were tested with Meridian Premier Coccidioides enzyme i mmunoassay (MPC-EIA), and the results were compared with those of conv entional serologic tests detecting complement-fixing (CF) and tube pre cipitin (TP) antibodies. Of the 73 positive specimens by CF; 72 were p ositive by MPC-EIA (71 IgG positive, 48 IgM positive) and 1 was indete rminate. Of the 132 specimens negative by CF, 126 were negative by MPC -EIA, 3 were IgM positive only, and 3 were indeterminate. Of the three patients with specimens positive of IgM only, CF demonstrated serocon version within a month in one. All 21 specimens that displayed anticom plementary activity by CF were confirmed negative by agar gel immunodi ffusion for CF antibodies (IDCF) and TP antibodies (IDTP); 20 of these serum samples were also negative by MPC-EIA, and 1 was indeterminate. After exclusion of the 25 specimens with anticomplementary of indeter minate activity, results of MPC-EIA were in agreement with those of CF in 99% of specimens. With CF as reference, MPC-EIA has a specificity of 98%, sensitivity of 100%, and positive and negative predictive valu es of 96% and 100%, respectively. Correlation coefficient values from linear regressions of log-2 CF titer vs MPC-EIA IgG index values were calculated at .290 for serum samples and .931 for cerebrospinal fluid.