Photobiomodulation With Blue LED in Recurrent Bacterial Vaginosis

Overview

Introduction: Bacterial vaginosis (BV) is the most prevalent vaginal dysbiosis in women of reproductive age and is associated with adverse gynecological and obstetric outcomes; therefore, its diagnosis and appropriate treatment are of significant clinical importance. National and international guidelines recommend the treatment of bacterial vaginosis with oral or vaginal metronidazole or vaginal clindamycin. However, approximately 50% of women experience recurrence of the disease one year after treatment. Persistence of residual disease, treatment resistance, reinfection, and biofilm formation hindering the effectiveness of antimicrobial therapy are cited as causes of recurrence, although the mechanism remains uncertain. Objective: To evaluate the efficacy of using 401 ± 5 nm blue light-emitting diodes combined with metronidazole in preventing the recurrence of bacterial vaginosis, and to compare the diagnostic accuracy of bacterial vaginosis using Amsel and Nugent criteria. Methods: A randomized clinical trial will be conducted including 40 sexually active women aged 18 to 60 years with a microscopic diagnosis of bacterial vaginosis according to Nugent criteria. Participants will complete a structured questionnaire and undergo a gynecological examination including vaginal pH measurement, amine testing, and 5 collection of vaginal contents for fresh microscopic examination and Gram staining. The diagnosis will be established according to the Nugent score criteria. The group will be randomized, with 20 participants allocated to the group receiving oral metronidazole treatment and 20 participants receiving oral metronidazole treatment combined with 401 +/- 5 nm Blue Light Emitting Diode therapy, lasting 15 minutes in 8 sessions. Participants will be evaluated by a gynecologist before, 21 days after, and 3 months after treatment. Statistical analysis will be performed with a significance level of 5%. Expected results: It is expected that treatment with 401 +/- 5 nm blue LED light, combined with conventional metronidazole treatment, be effective in reducing the recurrence of bacterial vaginosis. Conclusion: The findings may contribute to the planning of future studies to evaluate the effectiveness of the treatment in reducing the recurrence of vaginosis, with a potential impact on the prevention of adverse gynecological and obstetric outcomes.

Bacterial vaginosis (BV) is the most prevalent vaginal dysbiosis among women of reproductive age and is associated with several adverse gynecological and obstetric outcomes. Although effective antimicrobial treatments are available, recurrence remains frequent, with recurrence rates exceeding 50% within 12 months after treatment. The pathophysiology of BV involves disruption of the normal Lactobacillus-dominated vaginal microbiota and proliferation of anaerobic and facultative anaerobic bacteria, including Gardnerella vaginalis, Fannyhessea vaginae, Mobiluncus spp., Prevotella spp., and other bacterial taxa. These microorganisms may form polymicrobial biofilms on the vaginal epithelium, which can contribute to persistence of the condition and recurrence after antimicrobial treatment. Metronidazole is an established treatment for bacterial vaginosis. However, the high recurrence rate following conventional treatment highlights the need for complementary therapeutic approaches. Blue light has demonstrated antibacterial activity in previous experimental studies. One proposed mechanism involves the excitation of endogenous microbial photosensitizing chromophores, such as porphyrins and flavins, resulting in the production of reactive oxygen species that may exert cytotoxic effects on microorganisms. Previous clinical research has also investigated the safety of 401 ± 5 nm blue LED therapy on healthy vaginal mucosa. This randomized clinical trial will investigate whether the addition of 401 ± 5 nm blue light-emitting diode (LED) photobiomodulation to conventional oral metronidazole therapy can reduce the recurrence of bacterial vaginosis compared with oral metronidazole alone. The study will also assess the diagnostic performance of the Amsel and Nugent criteria for bacterial vaginosis. Clinical and laboratory assessments will be performed during the study according to standardized procedures, including gynecological examination, vaginal pH measurement, amine testing, fresh microscopy, and Gram staining. Participants diagnosed with bacterial vaginosis will receive standard oral metronidazole treatment. Participants allocated to the intervention group will additionally undergo eight sessions of blue LED therapy. The LED treatment will be administered at the study site by a trained professional using the study-specific device. Participants will be followed after treatment to assess clinical and laboratory findings and the occurrence of recurrent bacterial vaginosis. Statistical analyses will be performed according to the prespecified study protocol, using a significance level of 5%. The study is intended to provide preliminary clinical evidence regarding the potential role of blue LED photobiomodulation as an adjunct to conventional antimicrobial therapy for reducing bacterial vaginosis recurrence. The findings may support the development of larger randomized clinical trials evaluating this complementary therapeutic approach.