Trichomonas vaginalis as a cause of urethritis in Malawian men.

BACKGROUND AND OBJECTIVES: Trichomonas vaginalis is one of the most common sexually transmitted infections. In Malawi, rates of trichomoniasis in women are high. The prevalence of T. vaginalis infection in men is expected to be high but has not previously been documented. GOALS: We sought to determine the prevalence of trichomoniasis in Malawian men with and without urethritis, to evaluate a polymerase chain reaction detection assay for T. vaginalis in urethral swabs and to examine the effect of T. vaginalis infection on excretion of human immunodeficiency virus (HIV) in semen. STUDY DESIGN: Men presenting at the Sexually Transmitted Diseases (STD) and Dermatology Clinics in Malawi were enrolled in a cross-sectional study. We compared a polymerase chain reaction-based test for T. vaginalis detection with wet-mount microscopy and culture of urethral swabs. HIV serology was determined by enzyme-linked immunosorbent assay (ELISA), and HIV-1 RNA concentrations in semen were measured by quantitative nucleic acid sequence-based analysis. RESULTS: T. vaginalis was detected in 51 of 293 men. The estimated prevalence among symptomatic men was 20.8% and among asymptomatic men, 12.2%. Polymerase chain reaction performed with a sensitivity of 0.82 (95% CI: 0.66-0.92) and specificity of 0.95 (95% CI: 0.91-0.97) compared to wet-mount microscopy and culture. There was no difference in the rate of HIV seropositivity in men with and without T. vaginalis infection. However, in men with symptomatic urethritis, the median HIV RNA concentration in seminal plasma from men with T. vaginalis was significantly higher that in seminal plasma from HIV-positive men without trichomonas.

PIP: This study was conducted to determine the prevalence of trichomoniasis in Malawian men, to evaluate a polymerase chain reaction (PCR) detection assay for T. vaginalis in urethral swab samples, and to examine the effect of T. vaginalis infection on HIV excretion in the semen. There were 206 men with symptomatic urethritis in STD clinic and 127 asymptomatic men in the Dermatology Clinic who were enrolled from January to March 1996. Results, according to a wet-mount microscopy and urethral swabs culture combination, showed that, of 293 men, only 38 (13%) men were positive for T. vaginalis. The estimated prevalence among symptomatic and asymptomatic cases was 15.7% and 8.7%, respectively. The PCR yielded a sensitivity of 0.82 (95% CI: 0.66-0.92) and specificity of 0.95 (95% CI: 0.91-0.97); these were compared to the wet-mount microscopy and culture combination. Overall HIV seroprevalence of men was 51%, because gonococcal urethritis was shown to significantly increase seminal HIV RNA levels. The median HIV RNA concentration in seminal plasma from men with symptomatic urethritis plus T. vaginalis infection was significantly higher than in seminal plasma from HIV-positive men with symptomatic urethritis only. Since this study has several important limitations, a randomized clinical trial would be useful for determining whether urethritis cure rates can be significantly improved.

Association of CD4 cell depletion and elevated blood and seminal plasma human immunodeficiency virus type 1 (HIV-1) RNA concentrations with genital ulcer disease in HIV-1-infected men in Malawi.

CD4 cell counts and blood plasma and seminal plasma human immunodeficiency virus type 1 (HIV-1) concentrations were compared in HIV-1 RNA-seropositive men with urethritis and with or without genital ulcer disease (GUD). GUD was associated with lower CD4 cell counts (median, 258 vs. 348/microL) and increased blood plasma HIV-1 RNA (median, 240 x 10[3] vs. 79.4 x 10[3] copies/mL). Men with nongonococcal urethritis and GUD shed significantly greater quantities of HIV-1 in semen (median, 195 x 10[3] vs. 4.0 x 10[3] copies/mL) than men with nongonococcal urethritis without GUD. These levels decreased approximately 4-fold following antibiotic therapy. The results indicate an association between GUD and increased blood HIV-1 RNA levels. Increased HIV-1 in semen was demonstrated in some men with GUD; such an increase could lead to increased transmission, thus complicating interpretation of the role of the genital ulcer itself in the infectiousness of HIV. Reasons for increased HIV RNA in semen in men with GUD remain to be determined.