Treatment for Vaginal Swab Positive for Atopobium vaginae, BVAB2, and Megasphaera 1
The recommended first-line treatment for a vaginal swab positive for Atopobium vaginae, BVAB2, and Megasphaera 1 is oral metronidazole 500 mg twice daily for 7 days, which has the highest efficacy with a 95% cure rate. 1
First-Line Treatment Options
- Oral metronidazole 500 mg twice daily for 7 days is the preferred treatment recommended by the CDC with the highest efficacy (95% cure rate) 1, 2
- Patients should be advised to avoid alcohol during treatment and for 24 hours afterward due to potential disulfiram-like reaction 3, 1
- The organisms identified (Atopobium vaginae, BVAB2, and Megasphaera 1) are bacterial vaginosis-associated bacteria that respond to standard BV treatment 1
Alternative Treatment Options
- Metronidazole gel 0.75%, one full applicator (5g) intravaginally once daily for 5 days is equally effective as oral therapy but with fewer systemic side effects 1, 2
- Clindamycin cream 2%, one full applicator (5g) intravaginally at bedtime for 7 days is another effective first-line option 1, 3
- Oral metronidazole 2g as a single dose has lower efficacy (84% cure rate) compared to the 7-day regimen but may be useful when compliance is a concern 1, 2
- Tinidazole has shown efficacy in bacterial vaginosis treatment at doses of either 2g once daily for 2 days or 1g once daily for 5 days 4
Special Considerations
Allergy or Intolerance to Metronidazole
- Clindamycin cream or oral clindamycin 300 mg twice daily for 7 days is preferred for patients with allergy or intolerance to metronidazole 3, 1
- Patients allergic to oral metronidazole should not be administered metronidazole vaginally 3, 1
Pregnancy
- During first trimester: Clindamycin vaginal cream is preferred due to contraindication of metronidazole 3, 1
- During second and third trimesters: Metronidazole 250 mg orally three times daily for 7 days is recommended 1, 5
- Treatment of BV in high-risk pregnant women (history of preterm delivery) may reduce risk of prematurity 1, 2
Follow-Up and Management
- Follow-up visits are unnecessary if symptoms resolve 3, 1
- For recurrent BV, an extended course of metronidazole treatment (500 mg twice daily for 10-14 days) is recommended 6
- If the extended course is ineffective, metronidazole vaginal gel 0.75% for 10 days, followed by twice weekly for 3-6 months, is an alternative regimen 6
Management of Sex Partners
- Routine treatment of male sex partners is not recommended as it has not been shown to influence a woman's response to therapy or reduce recurrence rates 3, 1, 5
- This is because BV is not considered exclusively an STD, although it is associated with sexual activity 3
Treatment Efficacy Considerations
- The presence of Atopobium vaginae specifically may be associated with biofilm formation, which can protect BV-causing bacteria from antimicrobial therapy and lead to recurrence 6
- Persistence of Gardnerella vaginalis may occur after clinical cure, which could explain cases of recurrent disease 7
- Intravaginal products have fewer systemic side effects (mean peak serum concentrations of metronidazole following intravaginal administration are less than 2% of standard 500 mg oral doses) 3