INDIRECT IMMUNOFLUORESCENT ASSAY (IFA) IN BUFFY COAT AS A RAPID DIAGNOSTIC-TEST FOR INVASIVE CANDIDIASIS

In order to have a diagnostic test for invasive candidiasis, an immuno fluorescent assay (IFA) in buffy coat was developed and evaluated. Thi s test was compared to buffy coat culture and blood culture. The study was divided into two parts: evaluation of the diagnostic test in a ra bbit model, and for diagnosis in patients at high risk for invasive ca ndidiasis. Part I: Rabbits were experimentally infected. Of 13 rabbits with disseminated candidiasis blood was drawn from central venous cat heter and from peripheral veins. From catheters, Candida was detected in 13/13, 10/13 and 8/13, by buffy coat culture, IFA, and blood cultur e, respectively. From peripheral veins, Candida was detected in 10/10 by buffy coat cultures, in 6/10 by IFA and in 3/10 by blood cultures. The gold standard was histopathological diagnosis; sensitivity for IFA was 60% with peripheral blood and 76% with catheter blood samples. Pa rt II: IFA and blood cultures were compared in clinical samples from h ospitalized children. Forty patients were included. Candida was isolat ed from blood cultures in four patients whereas IFA detected Candida i n 22 patients. Differences were statistically significant (p <0.05). W e conclude that IFA in buffy coat smears is a reliable test to detect candidemia, and would be a useful tool to help physicians with treatme nt decisions with amphotericin B.