Characterization and Treatment of Recurrent Bacterial Vaginosis

Bacterial vaginosis (BV) is a common but treatable condition, with a number of effective available treatments, including oral and intravaginal metronidazole and clindamycin and oral tinidazole. However, as many as 50% of women with BV experience recurrence within 1 year of treatment for incident disease. Some reasons for recurrence include the persistence of residual infection, resistance, and possibly reinfection from either male or female partners. Persistence may occur due to the formation of a biofilm that protects BV-causing bacteria from antimicrobial therapy. Poor adherence to treatment among patients with genitourinary infections may lead to resistance. However, the underlying mechanisms of recurrent etiology of BV are not known. Recommended treatment for recurrent BV consists of an extended course of metronidazole treatment (500 mg twice daily for 10-14 days); if ineffective, metronidazole vaginal gel 0.75% for 10 days, followed by two times per week for 3-6 months, is an alternate treatment regimen. Past studies of clindamycin and tinidazole in the treatment of recurrent BV have focused on patients with evidence of metronidazole resistance. Secnidazole may be an attractive new option due to one-time dosing. Initial studies on biofilm disruption, use of probiotics and prebiotics, and botanical treatments have shown some promise, but must be studied further before use in the clinic. Despite limitations, antimicrobial therapy will remain the mainstay of treatment for recurrent BV for the foreseeable future.