The influence of focused ultrasound in the treatment of cervical squamous intraepithelial lesion on vaginal microbiota and cervical immune microenvironment: a prospective observational study

Purpose To observe the changes in the vaginal microbiota and cervical immune microenvironment following focused ultrasound treatment of cervical squamous intraepithelial lesions, with clinical efficacy assessed for contextual validation.Methods The case group comprised 50 patients with cervical squamous intraepithelial lesions who underwent focused ultrasound treatment and completed longitudinal collection of cervical secretions at pretreatment, 1–2 weeks, and (14 ± 2) weeks post-treatment. According to the treatment response at (14 ± 2) weeks, the case group was further classified into cure (histopathologically confirmed absence of SIL, or normal cytology and colposcopy) and improvement (decreased SIL level on histopathology or cytology with corresponding colposcopy) subgroups. These patients were compared with 17 healthy individuals (the control group). Changes in the levels of DEFB1, IFN-γ, IL-1β, IL-8, IL-10, SIgA, SLPI, and the Th1/Th2 ratio were measured in cervical secretions. Meanwhile, vaginal microbiota was examined in both groups at baseline and (14 ± 2) weeks post-treatment.Results (1) Following focused ultrasound treatment, levels of DEFB1, IL-1β, IL-8, SIgA, and SLPI in cervical secretions were significantly decreased at (14 ± 2) weeks post-treatment in the cure group compared with pretreatment levels (p < 0.05). (2) Compared with pretreatment levels in the cure group, vaginal microbiota indicators—including pH, Nugent score, bacterial diversity, bacterial density, and Lactobacillus abundance—were significantly normalized at (14 ± 2) weeks post-treatment (p < 0.05).Conclusions Focused ultrasound treatment may contribute to regression of cervical squamous intraepithelial lesions and may be associated with restoration of vaginal microbiota and cervical immune microenvironment.