Tehran University of Medical Sciences Iranian Journal of Parasitology 1735-7020 5 4 2010 12 15 9 14 EN F Kazemi Parasitology Dept., School of Medicine, Kashan University of Medical Sciences, Kashan, Iran H Hooshyar Parasitology Dept., School of Medicine, Kashan University of Medical Sciences, Kashan, Iran B Zareikar Parasitology Dept., School of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran M Bandehpour Cellular and Molecular Biology Research Center, Shahid Beheshti University, M.C., Tehran, Iran M Arbabi Parasitology Dept., School of Medicine, Kashan University of Medical Sciences, Kashan, Iran S Talari Parasitology Dept., School of Medicine, Kashan University of Medical Sciences, Kashan, Iran R Alizadeh Parasitology Dept., School of Medicine, Kashan University of Medical Sciences, Kashan, Iran B Kazemi Cellular and Molecular Biology Research Center, Shahid Beheshti University, M.C., Tehran, Iran AND Parasitology Dept., School of Medicine, Shahid Beheshti University, M.C., Tehran, Iran 2015 10 03 Background: Trichomoniasis is a worldwide protozoan parasitic disease and metronidazole is a choice drug for its treatment. Because of disease importance in public health and its controversial ideas about the prevalence of drug resistance, this study was carried out. Methods: Fifty-two suspected vaginal samples were collected from 2006 to 2007 in Gynecology Maryam Hospital, Tehran, Iran. All isolates were examined by microscopic, culture and PCR tech­niques. The PCR products were analyzed by RFLP and CSGE methods and two suspected samples were sequenced. Results: Trichomonas vaginalis was identified from all 52 samples. Of 52 isolates, 45 samples were successfully cultured and amplified by PCR except one. Seven were positive only by PCR. Finally, ITS1 fragment was successfully amplified in 51 of 52.  CSGE analysis and PCR products di­gestion by MspI followed by sequencing showed nucleotide mutation at position 209 (C209T) of the ITS1 fragment in two (3.9%) of them. Conclusion: The results showed mutation in ITS1 fragment of T. vaginalis in two (3.9%) of Ira­nian isolates which may be related to metronidazole resistance. https://ijpa.tums.ac.ir/index.php/ijpa/article/view/151 https://ijpa.tums.ac.ir/index.php/ijpa/article/download/151/150