Trends in Prevalence of Yeast Species Associated With Urogenital Infection in Nsukka, Nigeria: An Overview of True Candida Species and Genotyping of Candida albicans hwp1-Heterozygous Isolates.

Abstract

Pathogenic drug-resistant yeast species, associated with urogenital infections, are still not well-recognized in routine clinical laboratories. This study describes the prevalence and antifungal susceptibility profile of fungal species isolated from patients with urogenital infection in Nsukka, Nigeria. A total of 248 urogenital samples (voided urine, high vaginal swabs, urethral swabs, and semen) were cultured on specific mycological media for the isolation and presumptive identification of Candida and other yeast species. Further identification of fungal isolates was performed using conventional phenotypic techniques and molecular methods. Disk diffusion and broth dilution methods were used for the antifungal susceptibility study and determination of minimum inhibitory concentration (MIC), respectively. A total of 129 yeasts were isolated from 117 patients with urogenital infection. Candida albicans (73.64%) was the most prevalent species followed by Pichia kudriavzevii (Candida krusei) (9.30%) and Candida parapsilosis (6.20%), while Nakaseomyces glabrata (Candida glabrata) and Candida tropicalis exhibited the same frequency of occurrence (5.43% each). All Candida isolates were susceptible to voriconazole and nystatin, while reduced susceptibility to fluconazole was noted. All the germ tube-positive isolates were confirmed to be C. albicans by molecular methods although 15 of them were found to be heterozygous at hwp1 locus. This study describes the distribution of true Candida species causing urogenital infection in Nigeria and the level of susceptibility of these species to common antifungal drugs emphasizing the need for yeast culture and antifungal susceptibility testing as part of the routine test in medical diagnostic laboratories for the proper management of urogenital candidiasis.