Value of the Candida antigen assay in diagnosis of systemic candidiasis in burn patients.

The Cand-tec latex agglutination test was used to analyze 2,575 serum samples from 47 consecutive burn patients at risk for systemic candidiasis and serum samples from 24 nonhospitalized control subjects. One burn patient had systemic candidiasis documented by culture of a deep biopsy specimen. In addition, blood culture produced positive results in one patient with no other evidence of systemic candidiasis. Wound, sputum, mucous membrane, or gastrointestinal tract specimens were cultured in 25 of 47 (53%) patients with no evidence of systemic candidiasis. Surveillance cultures were negative in 19 (40%) patients and there were no signs of systemic candidial infection. The sensitivity of the Candida antigen titer was 100% at titers of greater than or equal to 1:2, greater than or equal to 1:4, greater than or equal to 1:8, and greater than or equal to 1:16. Specificity was 77% at titers of greater than or equal to 1:4, 94% at titers of greater than or equal to 1:8, and 100% at titers of greater than or equal to 1:16. The positive predictive value ranged from 6.0% at greater than or equal to 1:4 to 100% at greater than or equal to 1:16. The negative predictive value was 100% for all titer values. The Cand-tec antigen test shows poor specificity and poor positive predictive value for the detection of systemic candidiasis in burn patients.