Detection of candida antigenemia by counterimmunoelectrophoresis in patients with invasive candidiasis

Abstract

Because of the difficulty in diagnosis of invasive candidiasis, an assay that makes use of counterimmunoelectrophoresis (CIE) was developed to detect candida antigen. A cell-wall polysaccharide of Candida was extracted with hot formamide, ethanol precipitation, and gel filtration. Rabbit antiserum was tested by CIE against sera from 20 healthy individuals, 15 patients with mucosal candidiasis, and 48 compromised patients with cultures positive for Candida. Antigen was detected in sera from 13 patients by CIE; eight of these patients were eventually proven to have invasive disease. None of the antigen-negative patients for whom autopsy was performed had evidence of invasive candidiasis. Healthy individuals and patients with superficial mucosal candidiasis were also antigen-negative. The detection of candida antigenemia by CIE is specific for invasive disease and serves as a guide in initiation and follow through of antifungal therapy.