Abstract

MOLECULAR DETERMINATION OF ERG11 GENE IN FLUCONAZOLE RESISTANT STRAINS OF CANDIDA TROPICALIS

Kavitha M. K.* and Arun B.

Abstract

Candidiasis is one of the most prevalent and important opportunistic fungal infections, caused by Candida species. It is generally accepted that suspected Candida infections can be treated with amphotericin B (AmB), flucytosine, fluconazole, itraconazole, voriconazole and echinocandins. But, a challenging area in the field of candidiasis treatment is that the emergence of drug resistant Candida sp. is increasingly being reported. Objectives of the study includes molecular determination of drug resistant strains of Candida sp. The clinical samples were obtained from patients having the symptoms of candidiasis, attending the Obstetrics and Gynaecology Departments and Dermatology and Venereology Departments of a Tertiary care Hospital in North Kerala. Laboratory identification was performed and Antifungal Disk Diffusion Susceptibility Testing was done with Antimicrobial Disks − Voriconazole (VRC 1 mcg/disc), Fluconazole (FLC 25 mcg/disc), Itraconazole (IT 10 mcg/disc) and Amphotericin B (AP 100 units/disc) obtained from Himedia, Mumbai. Polymerase Chain Reaction (PCR) was performed in an attempt for molecular characterization of the fluconazole resistant C. tropicalis. During the study period, a total of 325 clinical samples were collected and 180 Candida isolates were obtained. Identification of fluconazole resistant ERG11 gene in fluconazole resistant C. tropicalis by Real Time PCR resulted in 17 (48.6%) positive strains and 18 (51.4%) negative strains out of a total of 35 fluconazole resistant isolates of C. tropicalis. This study highlights the fact that there is a risk of emergence of azole resistant strains of Non – Albicans Candida like C. tropicalis, which are increasingly being isolated from clinical specimens.

Keywords: C. tropicalis, ERG11 gene, Fluconazole resistant, Real Time PCR.