Prevalence and factors associated with genital Chlamydia trachomatis, Neisseria gonorrhoeae and Ureaplasma urealyticum infections among patients in a preexposure prophylaxis (PrEP) program at a single center in Bogotá, Colombia

Sexually transmitted infections (STIs) represent a diverse group of diseases increasingly observed among at-risk populations, including individuals using pre-exposure prophylaxis (PrEP). This observational, descriptive, cross-sectional study evaluated STIs prevalence and associated risk factors among patients enrolled in a PrEP program at a single center in Bogotá, Colombia, between July and September 2024. Diagnostic tests for STIs ( Neisseria gonorrhoeae , Chlamydia trachomatis and Ureaplasma urealyticum) were conducted, and univariate and multivariate analyses identified variables associated with higher prevalence. Prevalence ratios (PRs) with 95% confidence intervals (CIs) were calculated. The study included 185 patients, of whom most used a daily PrEP regimen (84.8%). The prevalence of infection with any of the three sexually transmitted infection-associated microorganisms was 24.9% (95% CI: 20.64%–29.08%). U. urealyticum was the most prevalent microorganism, identified in 35 of 46 cases (76.1%), followed by N. gonorrhoeae and C. trachomatis (19.5% each). The most frequent coinfection involved C. trachomatis and U. urealyticum (8.6%), with no triple coinfections observed. In multivariate analysis, group sex (PR: 6.33, 95% CI 2.37–18.2, p < 0.001) and fisting (PR: 2.18, 95% CI 1.37–3.49, p < 0.001) were independently associated with STIs prevalence. Patients with N. gonorrhoeae and C. trachomatis received treatment, while U. urealyticum cases were treated only if symptoms were present. The prevalence of STIs among PrEP users is high, with asymptomatic infections being the most common. High-risk sexual practices, such as group sex and fisting were strongly associated with an increased STIs prevalence. These findings highlight the critical importance of implementing regular STI screening and tailored prevention strategies to mitigate risk in this population. Not applicable.