Identification of Candida Species among Patients with Vulvovaginal Candidiasis in Kashan by PCR-RFLP Method

Vulvovaginal candidiasis (VVC) is a common vaginal infection, affecting up to 75% of women in child-bearing age. Approximately 5% of patients may experience recurrent VVC. Candida albicans is the most common causative agent with a prevalence of approximately 70–90%. Non-albicans Candida species, predominantly Candida glabrata, are responsible for the remainder. Precise diagnosis of causative agents of VVC is necessary for epidemiological purposes and for effective treatment.

One hundred and thirty three yeast isolates were collected from a gynecology clinic affiliated to Kashan University, Iran, during 2007-2009. Genomic DNA of each isolate was extracted from fresh cultures using FTA-card. The ITS1-ITS2 region was amplified by polymerase chain reaction (PCR) assay and was digested by the restriction enzyme HpaII. The products of restriction fragment length polymorphism (RFLP) were electrophoresed on agarose gel and the yeast species were determined according to differences in their electrophoretic band patterns.

Prominent species isolated from clinical specimens were Candida albicans responsible for 116 cases (87.2%), followed by 16 cases of C. glabrata (12%) and 1 case of C. kefyr (0.7%). The age bracket of 31-40 years had the highest and the age bracket of 11-20 years had the lowest frequency of occurrence.

Like the majority of similar studies performed in this field, the present study found Candida albicans as predominant species isolated from vulvovaginal candidiasis. As molecular diagnostic methods are rapid and reliable and as there are no any other studies that used PCR-RFLP for diagnosis of etiologic agents of VVC in Iran, we recommend this approach for other similar epidemiological studies.