Infecção pelo Treponema pallidum em homens que fazem sexo com homens em Campo Grande-MS

Abstract

Syphilis is a systemic infectious disease of chronic evolution that occupies a significant importance among the most frequent public health problems of the world. Multiple sexual partners and irregular condom use expose men who have sex with men (MSM) to the risk of acquiring sexually transmitted infections (STI) such as syphilis. The present study aimed to estimate the prevalence of Treponema pallidum infection and identify risk factors for this infection in gays and transvestites in Campo Grande city, MS. Between December 2012 to October 2013, MSM participants were interviewed using a structured questionnaire. Blood samples were collected and analyzed by enzyme immunoassay (EIA) for detection of anti-Treponema pallidum serological marker. EIA-reactive samples were serially diluted to quantify VDRL titers. Of the 430 MSM studied, 278 (64.7%) were gay and 152 (35.3%) transvestites. The overall prevalence of T. pallidum infection was 34.7 % (149/430; 95% CI: 30.2 - 39.1). The prevalence of T. pallidum infection was significantly higher in transvestites (50.0%; 95% CI: 21.1 - 31.4) than in gays (26.3%; 95% CI: 42.1 - 57.9) (p<0.001). The active infection (VDRL > 1:8) was suggestive in 17.5% (95% CI: 13.9 - 21.0) of MSM studied. Of these, 15.8% of gay and 75.7% of transvestites were commercial sex workers. The irregular condom use was reported by 61.4% of gays and 70.3% of transvestites during the previous 12 months. Most transvestites reported having had at least two sexual partners in the last week (69.7%) and illicit drug use (63.8%). Among gay, these variables were reported in 23.7% and 40.6%, respectively. Approximately 38.0% of gays and 21.0% of transvestites reported sex with a woman in the past 12 months. The sexual violence was observed in 13.5% of gays and 24.6% of transvestites. In multivariate analysis, aged 20-24 years (OR: 2.74; 95% CI: 1.30 – 5.78) and over 29 years old (OR: 2.86; 95% CI: 1.34 – 6.10), different specialized sexual behaviors (i.e., fetishes) (OR: 1.57; 95% CI: 1.03 – 2.40), history of genital ulcer in the last 12 months (OR: 1.62; 95% CI: 0.99 – 2.63) were found to be significant associated for Treponema pallidum infection in the gay group. Among transvestites participants, 30 years of age or older (OR: 1.97; 95% CI: 1.09 – 3.59), have had more than 10 partners in last week (OR: 1.43; 95% CI: 1.11 – 2.02) and HIV infection (OR: 1.48; 95% CI: 1.11 – 1.96) were independently associated with syphilis infection. Our study revealed a high prevalence of Treponema pallidum infection and sexual risk behaviors in both populations. This finding indicates the need and urgency for implementing specific strategies that include diagnosis and prevention to control the spread of this infection in population studied, in order to interrupt transmission chain of this infection in MSM and their sexual contact.