Screening for sexually transmitted diseases in human immunodeficiency virus-positive patients in Peru reveals an absence of Chlamydia trachomatis andidentifies Trichomonas vaginalis in pharyngeal specimens

To determine the prevalence of sexually transmitted diseases (STDs), we scr eened 107 human immunodeficiency virus-positive patients in Peru, where the virus is predominantly sexually transmitted. Patients had multiple risk fa ctors for STDs, and 38% of women and 50% of men had at least 1 STD (gonorrh ea, trichomoniasis, herpes simplex, anogenital warts, or syphilis seroposit ivity). No chlamydial infection was detected, even though infection rates i n the general population are 5%-12%. Patients receiving trimethoprim-sulfam ethoxazole (TMP-SMZ) for prophylaxis or treatment of respiratory infections were least likely to have cervicitis and/or urethritis (odds ratio, 0.37; 95% confidence interval, 0.15-0.89). Although not optimal treatment, admini stration of TMP-SMZ is effective against chlamydial infection. We speculate that the use of concomitant medications, such as TMP-SMZ, may be inadverte ntly preventing chlamydial infection in this population. Another finding wa s the presence of Trichomonas vaginalis in pharyngeal specimens of 3 men wi th histories of orogenital activity. This has not been previously reported and requires further study.