Identification of drug-resistant Candida species causing recurrent vulvovaginal candidiasis, a new report

Introduction and Objectives: To investigate the drug resistance in women with vulvovaginal candidiasis which has long been treated with azoles, susceptibility of Candida species isolated from VVC cases to clotrimazole and fluconazole and molecular screening of ERG3 gene in the azole resistant Candida species was performed.Materials and Methods: For the identification at the species level of isolated Candida species differential media, CHROM agar Candida, GT test and Corn meal agar were used and confirmed by PCR-RFLP. A disc diffusion method was performed based on the standard guidelines of the National Committee for Clinical Laboratory Standards to determine level of susceptibility against fluconazole and clotrimazole. An azole resistance factor, ERG3 mutant gene was screened. Results: Among all Candida isolates, 76.3% (74 cases) were Candida albicans followed by C. glabrata and C. krusei 9 (9.3% each) and other non albicans Candida species 4 (4.1%). From the C. albicans isolates resistant to Clotrimazole, 8(53.3%) had ERG3 gene and 7(46.7%) did not. Among all isolates resistant to Clotrimazole, 40% carried ERG3 mutant gene against 60% of others that did not show the gene. Also, in 50% of the isolated C. glabrata ERG3 mutant gene was detected. Conclusion: As a conclusion, the mutant ERG3 gene can be detected in a considerable number of azole resistant Candida species.

Keywords:

Candida , vulvovaginal candidiasis , drug resistant , ERG3