Dramatic Shift in the Etiology of Genital Ulcer Disease Among Patients Visiting a Sexually Transmitted Infections Clinic in Lilongwe, Malawi.

Background: Genital ulcer diseases (GUDs) are a common syndrome associated with sexually transmitted infections. Genital ulcer diseases increase the risk of HIV transmission, necessitating appropriate diagnosis and treatment. We provide an updated GUD etiology assessment in Malawi to guide diagnostic development and treatment algorithms.

Methods: We enrolled patients 18 years or older presenting with GUD at a sexually transmitted infection clinic in Lilongwe, Malawi, between May and October 2021. We purposively sampled by HIV status. Swabs of ulcers were tested for Treponema pallidum, herpes simplex virus (HSV)-1 and HSV-2, Haemophilus ducreyi, and Chlamydia trachomatis using polymerase chain reaction. Blood was collected for syphilis and HSV-2 serologies and acute HIV testing. Participants were treated per Malawi guidelines. Ulcer resolution (size reduced by >50%) was evaluated 14 days later.

Results: Fifty participants enrolled (30 without HIV, 2 with acute HIV infection, 18 with HIV seropositivity; 32 men, 18 women). Forty-six (92%) had an etiology identified. Syphilis was more common among those without HIV (22 of 30 [73%]) than participants with HIV (PWH; 8 of 20 [40%]; P = 0.04). Herpes simplex virus was more common among PWH (11 of 20 [55%]) than participants without (2 of 30 [7%]; P = 0.0002). One-fifth (9 of 50 [18%]) had H. ducreyi. Among those who returned for follow-up (n = 45), 9 (20%) had unresolved ulcers; persistent GUD was slightly more common in PWH (6 of 19 [32%]) than participants without (3 of 26 [12%]; P = 0.14).

Conclusions: We observed a dramatic increase in syphilis ulcer proportion in a population whose GUDs were previously HSV predominant. Observed differences in etiology and resolution by HIV status could play an important role in the ongoing transmission and treatment evaluation of GUD.