Influence of co-infection complicated with human papillomavirus on cervical intraepithelial neoplasia development in patients with atypical squamous cells of undetermined significance

Aim Human papillomaviruses (HPV) infection is a primary cause of the development of cervical precancerous lesions and cervical cancer. However, the influence of other infections on intraepithelial neoplasia (CIN) development has not been fully elucidated. We evaluated the association between co-infection and CIN development in subjects with atypical squamous cells of undetermined significance (ASCUS). Method Data for ASCUS subjects who had undergone testing for high risk HPV (HR-HPV) and pathological diagnosis were analyzed. From the CIN grade, HR-HPV and vaginal infection (VI) data, both the relationship between HPV infection and CIN development and the influence of co-infection on CIN were retrospectively evaluated. Results Data for 56 ASCUS subjects who had undergone HR-HPV testing and cytological diagnosis were analyzed. Positive rates were HPV (73.2%), HPV16 (21.4%), HPV18 (7.1%), and HPV16 and/or 18 (26.8%). Seventeen of the subjects were diagnosed as having one or more VI pathogen; the major pathogens found were Candida spp., Gardnerella vaginalis, group B streptococcus, coagulase negative Staphylococcus, and Chlamydia trachomatis. The rate of CIN 2 or worse (≥CIN 2) was significantly higher in subjects positive for HPV16 compared with HPV negative subjects, and was significantly higher in subjects with a VI complicated with HPV compared to those without a VI. Univariate and multivariate logistic regression analysis identified positive for HPV16 and/or 18 and positive for VI to be significant variables for ≥ CIN 2. Conclusion Our results indicate that having a vaginal infection complicated with HR-HPV affects the development of CIN in subjects with ASCUS cytology.