Trichomonas vaginalis infection in male sexual partners: implications for diagnosis, treatment and prevention

(See the editorial commentary by Van Der Pol on pages 23–5) Background. Trichomonas vaginalis causes a common sexually transmitted infection (STI) in women, yet trichomoniasis in male sexual partners is not well recognized. Nucleic acid amplification tests can increase detection of T. vaginalis in men compared with culture. Methods. We conducted a prospective, multicenter study to evaluate T. vaginalis infection among male partners of women with trichomoniasis and factors associated with infection by recruiting patients from 3 public clinics in the United States. Male partners were tested for concordant T. vaginalis infection, defined as a positive urethral culture, urine culture, or urine polymerase chain reaction (PCR) result. A subset of men also provided a semen sample for T. vaginalis culture and PCR. Factors associated with concordant infection were determined from bivariable and multivariable analyses. Results. We enrolled 540 women with trichomoniasis (diagnosed using wet mount microscopy and/or culture) and 261 (48.4%) of their male partners. T. vaginalis infection was detected in 177 (71.7%) of 256 male partners (95 % confidence interval [CI], 66.0%–77.3%), of whom 136 (77.3%) were asymptomatic. A vaginal pH of 14.5 in a woman was independently associated with infection in the male partner (adjusted odds ratio, 2.5; 95 % CI, 1.0–6.3). Younger male age (20–29 and 30–39 years) was also found to be an independent risk factor for concordan