Management of metronidazole-resistant Trichomonas vaginalis – a new approach

Abstract

Metronidazole-resistant trichomoniasis is an infrequent but challenging problem with no universally successful treatment. Since 1994, we have been using a combination regimen consisting of high-dose tinidazole plus a broad-spectrum antibiotic, i.e. doxycycline or ampicillin, and clotrimazole pessaries, for 7–14 days in this condition. A retrospective case review identified 11 cases of resistant trichomonas between 1994 and 2002. In the absence of resistance testing, resistance was defined clinically. Nine of the 11 patients were cured; one patient did not attend follow-up. In the women who attended for follow-up, the cure rate was 90%. We have found the combination of tinidazole, a broad-spectrum antibiotic, and clotrimazole pessaries to be a tolerable and effective treatment for metronidazole-resistant Trichomonas vaginalis. Although a variety of total doses of tinidazole were used in our patients, based on our findings, and those of others, we would recommend giving tinidazole 2g twice daily for 14 days (total dose 56g).