Introduction Both Trichomonas vaginalis (TV) and bacterial vaginosis (BV) cause vaginitis and place women at higher risk for HIV infection. Both are treated with metronidazole (Mtz) but at different doses. The purpose of this study was to examine the co-occurrence of these infections and BV treatment outcomes among TV+/BV+ women multi-dose Mtz for the treatment of TV.
Methods Women attending three sexually transmitted disease clinics in the southern US who had a diagnosis of TV (culture or NAAT confirmed) were interviewed and examined for BV using a Nugent score ≥7. Women were randomised to either 2 g single dose or 500 mg Mtz BID for 7 days multi-dose for the treatment of TV and followed 3–12 weeks post TV treatment and retested for both TV and BV. Medical records were abstracted for Amsel criteria for a subset of the cohort.
Results Of 528 TV+ women at baseline, 49.8% also had BV per Nugent score, 44.3% reported a history of BV and 5.9% also had yeast. Of 289 women whose medical records were abstracted, 23.5% had a vaginal discharge consistent with BV (i.e. thin and white/grey), and 34.1% were BV+ per Amsel at baseline. Of the 46 women who were BV+ at baseline per Amsel (i.e. diagnosed at point of care) and per Nugent (i.e. lab diagnosed) and were treated with multi-dose Mtz, 96% reported taking all their medicine. While 36% of these women reported condomless sex during follow-up, there was no association between sexual exposure and BV status at TOC. Of these 46 women, 42.9% remained BV+ at TOC and 19.4% reported BV-related symptoms. BV status at TOC was not associated with TV cure rates (p>0.56).
Conclusion A high rate of BV co-infection (49.8%) was found among women with TV, much of which was asymptomatic. The rate of BV persistence post multi-dose Mtz was also high both microbiologically (42.9%) and clinically (19.4%) and did not appear to be influenced by TV treatment status. Additional research and development of novel therapeutics (i.e. biofilm disruptors) are urgently needed for women with BV, particularly among TV+ women where BV rates are high.