Cervical HPV Infections, Sexually Transmitted Bacterial Pathogens and Cytology Findings-A Molecular Epidemiology Study

Abstract

Prevalent cervical HPV infection and high-risk HPV persistence consequences have been extensively investigated in the literature; nevertheless, any causative interrelations of other sexually transmitted bacterial infections (STIs) with cervical HPV infection have not yet been fully elucidated. This study aimed to investigate the possible association of STIs with cervical cytology aberrations and HPV genotyping results in a representative sample of predominantly young Greek women. Liquid-based cytology and molecular detection for bacterial STIs and HPV as well as extended HPV genotyping were simultaneously assessed in cervical samples from 2256 individuals visiting several urban outpatient Gynecology Departments for well-woman visits or cervical screening throughout a 20-month period. All specimens were centrally processed with validated molecular assays. The mean age of the studied women was 37.0 ± 11.7 years; 722 women (33.30%) tested positive for STI (mean age 34.23 ± 10.87 years). A higher mean age (38.34 ± 11.83 years (p < 0.05)) was associated with negative STI testing. Chlamydia trachomatis was detected in 59 individuals (8.2%), Mycoplasma hominis in 156 (21.6%), Mycoplasma genitalium in 14 (1.9%), and Ureaplasma spp. in 555 (76.9%); infections with two bacterial pathogens were identified in 73 samples (10.1%). Cervical HPV was detected in 357 out of 1385 samples with a valid HPV typing result (25.8%). The mean age of HPV-positive women was 32.0 ± 8.4 years; individuals testing HPV-negative were slightly older (N = 1028): 34.4 ± 9.2 (p < 0.05). Among the 1371 individuals with valid results both for bacterial STIs and cervical HPV detection, women with an HPV-positive sample were more likely to harbor an STI (OR: 2.69, 95% CI 2.10-3.46, p < 0.05). Interestingly, bacterial STI positivity illustrated significant heterogeneity between NILM and LSIL cases, with 28.88% of NILM and 46.33% of LSIL cases harboring an STI, respectively (p < 0.05). In brief, in a population with a high prevalence for STIs, especially Ureaplasma spp., an association was documented between bacterial pathogen detection and cervical HPV infection, as well as abnormal cytology; these findings merit further investigation.

Keywords: Chlamydia trachomatis; HPV; Mycoplasma genitalium; Mycoplasma hominis; Papanicolaou smear; Ureaplasma urealyticum; bacteria; cervical pathogens; cervical screening; epidemiology; human papillomavirus; public health; sexually transmitted infections.

Figure 1

Venn diagram indicating the number of available valid data for each examination type. The total number of cases that had at least one valid outcome from HPV, STIs, and LBC were 2256. The number of women with valid HPV, LBC, and STI test were 1385, 1806, and 2168, respectively. Intersection of two circles shows the number of valid results for both sets, for instance, simultaneous HPV and STI test was available for 1371 women, while, for HPV and STIs and LBC, for 1198 women.

Figure 2

Box and whisker plot of women’s ages for each cytological diagnostic category.