Simplified adsorption method for detection of antibodies to Candida albicans germ tubes

Two modifications that simplify and shorten a method for adsorption of the antibodies against the antigens expressed on both blastospore and germ tube cell wall surfaces (methods 2 and 3) were compared with the original method of adsorption (method 1) to detect anti-Candida albicans germ tube antibodies in 154 serum specimens. Adsorption of the sera by both modified methods resulted in titers very similar to those obtained by the original method. Only 5.2% of serum specimens tested by method 2 and 5.8% of serum specimens tested by method 3 presented greater than one dilution discrepancies in the titers with respect to the titer observed by method 1. When a test based on method 2 was evaluated with sera from patients with invasive candidiasis, the best discriminatory results (sensitivity, 84.6%; specificity, 87.9%; positive predictive value, 75.9%; negative predictive value, 92.7%; efficiency, 86.9%) were obtained when a titer of > or = 1:160 was considered positive.