Molecular identification and antifungal susceptibility of Candida albicans isolated from Vulvovaginitis Candidiasis

Document Type: Research Article

Authors

1 Department of microbiology, damghan Branch, Islamic Azad University, damghan, Iran, social security organization, Golestan, Iran

2 Department of microbiology, damghan Branch, Islamic Azad University, damghan, Iran,

3 Invasive Fungi Research Centre, Department of Medical Mycology & Parasitology, School of Medicine, Mazandaran, University of Medical Sciences, Sari, Iran

Abstract

Vulvovaginal candidiasis is caused by the increasing number of Candida species as normal flora in the vagina. To assess the transmission rout as well as to determine the suitable antifungal drugs for treatment, the exact identification of Candida species is crucial. Therefore, earlier detection of infection allows quick initiation of antifungal therapy with a greater probability for improved survival. The aim of this study was to evaluate the identification of Candida albicans using restriction fragment length polymorphism(RFLP) and to determine the in vitro susceptibility against four antifungal drugs. In this study, 100 clinical samples were obtained from the patients with suspected Vulvovaginal Candidiasis. Early identification of the grown yeasts was performed by physiological tests. Universal primers used to amplify the internal transcribe spacer region. Subsequent restriction enzyme analysis of PCR products was done using Msp1 and Bln1 which allows us to identify the most medically important C.albicans and C.dubliniensis. Antifungal  susceptibility  test  was  performed  according  to  the CLSI  M27-A3  broth  microdilution  method,  and  minimal  inhibitory  concentrations  were  determined  for  Nystatin,  Fluconazole,  Amphotericin B  and  Itraconazole. Fifty eight of 100 Candida species were isolated from suspected samples in which 36 isolates were identified as Candida albicans/ C.dubliniensis by using PCR-RFLP method as well as physiological test. Among them, only 1 isolate was identified as C.dubliniensis. All C.albicans isolates were susceptible to Amphotericin B and Nystatin. However, 5 C.albicans isolates were resistant to Fluconazole with MICs ≥ 64 μ g/ml (13.89%) and 4 isolates were resistant to Itraconazole with MICs ≥ 1 μ g/ml (11.11%). C.albicans is still the predominant species causing Candida-related infections. Nevertheless, the number of isolated yeasts from other species is growing gradually. Identification of Candida at species level is very important due to the increasing trend in the number of Candida isolates which have high MICs against antifungal agents.

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