The clinical diagnosis of trichomoniasis

Two hundred twenty-six consecutive women attending an inner-city clinic for sexually transmitted diseases were evaluated. Problem-directed histories and physical examinations were conducted and vaginal specimens for wet preparation and Trichomonas vaginalis culture were obtained from each patient. One hundred patients were found to be infected. Patients with multiple sex partners were found to be at increased risk of trichomoniasis (P less than .05). Those with abnormal discharge noted on examination had a higher frequency of positive cultures for T vaginalis (P less than .001). Only 50% of patients with trichomoniasis had an abnormal discharge. Patients with greater than 10 white blood cells per high power field on wet preparation, regardless of whether trichomonads were visualized, had a higher incidence of trichomoniasis (P less than .01). Factors that were not associated with Trichomonas infection included patient age, frequency of coitus, date of most recent coitus, day of menstrual cycle on which patient was examined, recent antibiotic use, use of contraceptives or specific contraceptive methods, symptoms of discharge or pruritus, or the finding of Leptothrix on wet preparation. These data support the contention that the classic description of trichomoniasis cannot be uniformly relied upon for diagnosis, but that patients with multiple sex partners, abnormal vaginal discharge and/or greater than 10 white blood cells per high power field on wet preparation are at increased risk of infection by T vaginalis.