Microbial diversity in the vaginal microbiota in women with high-grade squamous intraepithelial lesion

Aim. To study the types of vaginal microbial communities in women with high-grade squamous intraepithelial lesion (HSIL) and those negative for intraepithelial lesion or malig­nancy (NILM). Materials and Methods. Between 2021 and 2023, we conducted an analysis of vaginal microbial com­munity types among 70 women of reproductive age infected with high-risk oncogenic HPV: those with HSIL verified by cytological examination (n = 40) and those without precancerous cervical lesions (i.e., NILM, n = 30). Identification of microorganisms in the cervical mucus was identified by mass spectrometry. Results. The frequency of normal microbiota detected by the microscopic examination was 5.3-fold lower, whilst Streptococcus spp. was detected 3-fold times higher in women with HSIL compared to the NILM group ( p = 0.023). Among patients with HSIL, community state type (CST) IV was the most frequent (75%), and CST IV-C1 subtype (with Streptococcus spp. as a prevailing genus ) was found in 25% of cases ( p = 0.132). In patients with NILM, CST IV was also the predominant type (60%) but CST IV-C2 (with En­terococcus spp. as a prevailing genus ) was most frequent subtype (23.3%, p = 0.087). The prevalence of HPV type 16 and grade 2 abnormal colposcopy findings were 3.9-fold ( p = 0.008) and 3.5-fold ( p = 0.040) higher in women with HSIL than in NILM ( p = 0.008). Conclusion. The predominant type among vaginal microbial communities in women with HSIL and NILM was CST IV, with C1 and C2 subtypes pre­vailing respectively in HSIL and NILM.