Comparative prevalence of infection with Trichomonas vaginalis among men attending a sexually transmitted diseases clinic.

OBJECTIVE: Although established in women as a common cause of vaginal discharge, the prevalence of Trichomonas vaginalis (TV) in men compared with other classic urethral pathogens has not been well characterized. To assess this issue, the authors compared the prevalence of Neisseria gonorrhoeae (GC), Chlamydia trachomatis (CT), and TV in consecutive men attending a sexually transmitted diseases (STD) clinic.

METHODS: From June 1, 1998 to July 27, 1998, 454 consecutive men presenting to the Denver Metro Health Clinic with a new problem were tested for GC by urethral swab culture, for CT by polymerase chain reaction of urine, and for TV by urine sediment culture.

RESULTS: GC, CT, and TV were detected in 23 (5.1%), 34 (7.5%), and 13 (2.8%) of men, respectively. There were significant differences by age for both CT (11.3% in men younger than 30 years versus 3.3% in men 30 years and older, P < 0.05) and TV (0.8% in men younger than 30 years versus 5.1% in men 30 years and older, P < 0.05). In 50 men 30 years or older with symptoms of urethral discharge, TV prevalence (12.0%) rivalled that of GC (12.0%) and CT (14.0%). In 45 men 30 years and older with nongonococcal urethritis, the prevalence of TV and CT were each 13.3%. Multivariate logistical regression analysis showed the presence of discharge and nongonococcal urethritis in men 30 years and older to be an independent predictor of TV.

CONCLUSIONS: TV is common in men attending sexually transmitted disease clinics, especially in those 30 years or older, in whom it may account for as much urethritis as GC or CT. These findings suggest that in older men with nongonococcal urethritis, diagnostic evaluation, empiric treatment, and partner management should include the possibility of TV infection.