The Prevalence and Genotype Distribution of Cervical Human Papillomavirus DNA in Women with Normal Cytology in North of Iran

Abstract

Background: Cervical cancer is a leading cause of mortality in women. Infection with high-risk human papillomavirus (HPV) is recognized as an important etiological factor for the development of cervical cancer. On the other hand, cervical cancer screening can detect abnormal cervical cells and diagnose cervical cancer in the early stages. Objectives: This study was performed to determine and analyse the distribution of HPV genotypes in normal cervical tissues, using polymerase chain reaction in Mazandaran province in North of Iran. Methods: This cross-sectional study was performed during 2012 - 2015. Tissue samples from the cervix were collected from 450 women, referring to a healthcare centre in Mazandaran province, Iran. Pap smear was used to monitor any abnormalities or unusual findings. Also, GP5 + / GP6 + primers were applied for the detection of HPV DNA in the specimens. Afterwards, positive samples were selected to perform high-risk HPV genotyping, using the HPV HCR DNA genotyping kit. Results: In this study, 431 (95.78%) samples were found to be normal on the Pap smear test, while 19 (4.22%) samples were abnormal. We found that the rate of positive HPV DNA was 10.22% in the tissue cervix samples. Human papillomavirus DNA was detected in 8.12% (35 of 431) of the normal tissues and 57.89% (11 of 19) of the abnormal tissues. From the 46 HPV DNA positive samples, 19 (41.30%) were HPV16, 9 (19.57%) of which were HPV18 and 1 (2.17%) was HPV45. In this study, the highest prevalence of HPV DNA was found in women within the age range of 20-24 years, which constitutes 20 (28.17%) of the HPV DNA positive samples. Conclusions: Cervical cancer screening, comprising of both Pap test and HPV testing, is an essential part of the routine health care for women as it can facilitate the detection of abnormal cervical cells. HPV infection can produce abnormal Pap test results; also, certain types of HPV are associated with cancer. Therefore, it is important to diagnose abnormal cervical tissues before the development of cervical cancer.