Reactive nitrogen intermediates in experimental trichomoniasis induced with isolates from symptomatic and asymptomatic women.

Trichomoniasis is the interplay between the infecting parasite, Trichomonas vaginalis, and the host, on which the clinical presentation of the disease depends. Although the clinical spectrum varies from an asymptomatic state to mild, moderate or severe symptoms, the exact virulence markers of T. vaginalis have not been well elucidated. Free radical generation during the disease process and its role in pathogenesis has been reported in various microbial diseases. In the present study, an attempt has been made to study reactive nitrogen intermediate (RNI) concentrations in experimental animals infected with T. vaginalis isolates from symptomatic and asymptomatic women. A significant increase in polymorphs, vaginal epithelial cells and RNI levels was observed in mice infected with isolates from symptomatic and asymptomatic subjects as compared to uninfected controls. The mean concentration of RNI in the vaginal tissue of mice infected with isolates from symptomatic women (75.5+/-7.7) was significantly higher than that of the vaginal tissue of mice infected with isolates from asymptomatic women (47.9+/-7.8), while it was less in the vaginal washes and plasma of mice infected with isolates from symptomatic women (18.7+/-3.6 and 17.1+/-3.3, respectively) compared to those infected with isolates from asymptomatic women (28.9+/-7.3 and 26.7+/-4.4, respectively), which may be due to different macrophage populations with different functional capabilities. Our study indicates that RNI production may play a role in establishing the infection.