Phenotypic and genotypic evaluation of fluconazole resistance in vaginal Candida strains isolated from HIV-infected women from Brazil

Abstract

We conducted a study to determine the antifungal susceptibility of vaginal Candida isolates from HIV-infected Brazilian women. Among 127 women enrolled, positive cultures for yeast were obtained from 31 of 38 (81%) women with symptomatic vulvovaginitis, and from 41 of 89 (46%) asymptomatic women. Susceptibility testing demonstrated 11 of the 72 isolates had either resistance or dose-dependent susceptibility to azole drugs, including four Candida albicans strains. Expression of the MDR1, CDR1, CDR2 and ERG11 genes was evaluated in all of the C. albicans isolates, and all four of the strains with reduced susceptibility to fluconazole had increased expression of CDR1 as compared to the fluconazole-sensitive strains. No increased expression of the other genes was identified. This large survey of Candida isolates from HIV-infected women from Brazil demonstrates that reduced susceptibility to azoles occurs at a low frequency among vaginal yeast isolates, and when present in C. albicans, azole resistance is associated with increased expression of CDR1. © 2005 ISHAM.