From the Guidelines
For a symptomatic female with 3 confirmed Gardnerella vaginalis infections in 12 months, I recommend treatment with oral metronidazole 500 mg twice daily for 7 days. This is the first-line therapy for recurrent bacterial vaginosis (BV) as per the guidelines from the Centers for Disease Control and Prevention 1. Alternatives include metronidazole gel 0.75% intravaginally once daily for 5 days or clindamycin cream 2% intravaginally at bedtime for 7 days.
Some key points to consider in the management of this condition include:
- The benefits of therapy for BV in nonpregnant women are to relieve vaginal symptoms and signs of infection, and reduce the risk for infectious complications after abortion or hysterectomy 1.
- Treatment of the male sex partner has not been beneficial in preventing the recurrence of BV, and therefore, male partners typically do not require treatment 1.
- After completing the initial treatment, consider a suppressive regimen with twice-weekly metronidazole gel for 4-6 months to prevent recurrence.
- The patient should avoid douching, use condoms consistently, and consider probiotics containing Lactobacillus species to help restore normal vaginal flora.
- Recurrent BV occurs when the normal vaginal microbiome, dominated by Lactobacillus species, is repeatedly disrupted, allowing overgrowth of anaerobic bacteria including Gardnerella vaginalis, leading to an increase in vaginal pH and the characteristic symptoms of abnormal discharge, fishy odor, and sometimes irritation or discomfort.
Follow-up visits are unnecessary if symptoms resolve, but recurrence is not unusual, and patients should return for additional treatment if symptoms recur 1.
From the Research
Treatment Options for Recurrent Bacterial Vaginosis
- The patient has had 3 confirmed Gardnerella vaginalis swab tests in 12 months, indicating recurrent bacterial vaginosis (BV) 2.
- Recommended treatment for recurrent BV includes an extended course of metronidazole treatment (500 mg twice daily for 10-14 days) or metronidazole vaginal gel 0.75% for 10 days, followed by two times per week for 3-6 months 2.
- However, studies have shown that Gardnerella vaginalis isolates from cases with recurrence of infection are often resistant to metronidazole 3.
Antibiotic Resistance and Treatment Efficacy
- Clindamycin therapy has been shown to have better clinical efficacy than metronidazole in cases of recurrent bacterial vaginosis, with 76% of Gardnerella vaginalis isolates sensitive to clindamycin 3.
- A study comparing the efficacy of oral metronidazole versus oral ampicillin for the treatment of urinary tract infection (UTI) by Gardnerella vaginalis found that ampicillin is effective, safe, and well-tolerated, while metronidazole is effective but not safe and poorly tolerated 4.
- Another study found that clindamycin exhibits a relatively higher susceptibility rate and lower resistance rate compared to metronidazole against Gardnerella vaginalis in both planktonic and biofilm formation 5.
Single-Dose Metronidazole Treatment
- A randomized, nonblinded study evaluated the efficacy of a single 2-g oral dose of metronidazole versus a seven-day regimen in the treatment of "nonspecific" vaginitis, with no significant difference in cure rates between the two groups 6.
- However, the effectiveness of single-dose metronidazole treatment for recurrent BV is unclear, and further studies are needed to determine its efficacy in this context 2, 6.