The Etiology of Genital Ulcer Disease and Coinfections With Chlamydia trachomatis and Neisseria gonorrhoeae in Zimbabwe: Results From the Zimbabwe STI Etiology Study

Abstract

In many countries, sexually transmitted infections (STIs) are treated syndromically. Thus, patients diagnosed as having genital ulcer disease (GUD) in Zimbabwe receive a combination of antimicrobials to treat syphilis, chancroid, lymphogranuloma venereum (LGV), and genital herpes. Periodic studies are necessary to assess the current etiology of GUD and assure the appropriateness of current treatment guidelines. We selected 6 geographically diverse clinics in Zimbabwe serving high numbers of STI cases to enroll men and women with STI syndromes, including GUD. Sexually transmitted infection history and risk behavioral data were collected by questionnaire and uploaded to a Web-based database. Ulcer specimens were obtained for testing using a validated multiplex polymerase chain reaction (M-PCR) assay for Treponema pallidum (TP; primary syphilis), Haemophilus ducreyi (chancroid), LGV-associated strains of Chlamydia trachomatis, and herpes simplex virus (HSV) types 1 and 2. Blood samples were collected for testing with HIV, treponemal, and nontreponemal serologic assays. Among 200 GUD patients, 77 (38.5%) were positive for HSV, 32 (16%) were positive for TP, and 2 (1%) were positive for LGV-associated strains of C trachomatis. No H ducreyi infections were detected. No organism was found in 98 (49.5%) of participants. The overall HIV positivity rate was 52.2% for all GUD patients, with higher rates among women compared with men (59.8% vs 45.2%, P < 0.05) and among patients with HSV (68.6% vs 41.8%, P < 0.0001). Among patients with GUD, 54 (27.3%) had gonorrhea and/or chlamydia infection. However, in this latter group, 66.7% of women and 70.0% of men did not have abnormal vaginal or urethral discharge on examination. Herpes simplex virus is the most common cause of GUD in our survey, followed by T. pallidum. No cases of chancroid were detected. The association of HIV infections with HSV suggests high risk for cotransmission; however, some HSV ulcerations may be due to HSV reactivation among immunocompromised patients. The overall prevalence of gonorrhea and chlamydia was high among patients with GUD and most of them did not meet the criteria for concomitant syndromic management covering these infections.