Combined vaginal treatment is more effective for bacterial vaginosis

Question Are metronidazole plus nystatin vaginal ovules a more effective treatment for bacterial vaginosis than metronidazole gel (Metrogel)?

Synopsis In Peru, the most commonly prescribed medication for treatment of vaginal discharge or malodour is intravaginal ovules with metronidazole 500 mg plus nystatin 100 000 U to be used nightly for five to seven nights. Researchers from Peru and the University of Washington compared the combined product with metronidazole 0.75% gel (Metrogel), 37.5 mg in one prefilled applicator nightly for five nights. Healthcare providers were blinded to treatment assignment, but patients knew which treatment they were using. The person who evaluated the diagnosis of bacterial vaginosis at follow up visits was also blinded to the treatment received. Women (n = 151) were enrolled if they complained of vaginal discharge or malodour and met criteria for diagnosis of bacterial vaginosis when at least three of four Amsel's criteria were present and a Gram stain had a Nugent score of 7-10. Follow up visits were at 14, 42, and 104 days after the baseline visit. A total of 138 (91%) of the women returned for evaluation at least once; 75 (50%) returned for all three follow up visits. At first follow up, five of 69 (7%) women treated with the ovules versus 18 of 69 (26%) treated with gel met both sets of criteria for diagnosis of bacterial vaginosis (number needed to treat = 5; 95% confidence interval 3 to 15). At subsequent visits the percentages were 17% v 38% and 33% v 52%, respectively.

Bottom line Metronidazole plus nystatin ovules resulted in higher cure rates than metronidazole gel in women with symptomatic bacterial vaginosis in this small study. It is not clear whether the better results were due to the higher metronidazole dose or the addition of nystatin. The combined product has not yet been marketed in the United States.

Level of evidence 1b (see www.infopoems.com/levels.html). Individual randomised controlled trial (with narrow confidence interval).