Background: In spite of sufficient knowledge about phenotypic variation of Trichomonas vaginalis, its genetic characteristics are poorly understood. We carried out a molecular epidemiology study in which in vitro metronidazole susceptibility of T. vaginalis isolates was considered.
Methods: This study was conducted on 862 women admitted to Gynecology Clinics in Hamadan, west of Iran, during 2014-2015. After recording the socio-demographic and clinical characteristics of participants, vaginal swab samples were taken and subjected to microscopic examination, culture, in vitro sensitivity testing and PCR-restriction fragment length polymorphism (RFLP) analysis.
Results: T. vaginalis was detected in 1.9% (16/862) of the samples using two parasitological methods. The all T. vaginalis isolates that subjected to drug susceptibility analysis were sensitive to metronidazole with MICs ranged from 0.4 to 12.8 µg/ml. T. vaginalis genotyping by using actin gene and PCR-RFLP analysis identified three actin type; A (9, 56%), I (6, 38%) and E (1, 6%). No significant correlation was observed between actin genotypes and their clinical manifestation (P>0.05).
Conclusion: The prevalence of T. vaginalis infection is not noticeable in the region and the most of isolates are hypersensitive to metronidazole. Further studies are needed to clarify the efficiency of the actin gene, as a reliable genetic marker, for molecular epidemiology of trichomoniasis.