Evaluation of a latex agglutination test for the identification of Candida species in vaginal discharge.

BACKGROUND The diagnosis of Candida vulvovaginitis using historical symptoms, pelvic examination findings, and results of traditional in-office laboratory tests is often inaccurate. Although Candida cultures can verify the diagnosis, they are not routinely used. METHODS We prospectively compared the accuracy of a commercially available, in-office, rapid, latex agglutination test (CandidaSure) for the identification of Candida species with results from Candida culture. RESULTS The sensitivity of the latex agglutination test was 66 percent and the specificity was 63 percent when compared with Candida culture results in patients with vaginal symptoms. When compared with a microscopic evaluation using potassium hydroxide (KOH), the CandidaSure test had greater sensitivity but a lower specificity. In 74 percent of cases with a positive KOH preparation, yeast forms were present on culture, and little was gained by adding the CandidaSure test in this situation. The addition of the CandidaSure test in those cases with a negative KOH preparation resulted in increased sensitivity but also increased the number of false-positive diagnoses. CONCLUSIONS The CandidaSure test has greater sensitivity than the KOH preparation, but it is less predictive of a positive culture. Because of this limitation, Candida should be documented by culture for any patient who has recurrent or persistent disease and a negative KOH slide.