Increasing incidence of Mycoplasma genitalium is driven by people living with HIV and PrEP users

Background: Mycoplasma genitalium (MG) is responsible for non-gonococcal urethritis. Our aim is to describe MG positivity rate and incidence in specific populations. Methods: Retrospective, surveillance study included all samples collected from 2018 to 2022. All samples were tested with Anyplex II STI7 (Seegene). Incidence rate (IR) was calculated, incidence rate ratios (IRRs) were assessed using Poisson regression model. Results: The study included 13,504 samples belonging to 7,692 individuals. Overall positivity rate was 2.9% (95%CI 2.6–3.2). Subgroups showed significant differences: 13.6% in PrEP users, 5.2% in STI clinic, 4.6% in people living with HIV (PLWH), 1.2% in Gynecology/Obstetrics Department, 0.5% in Fertility clinic, and 0.5% in the “Other” group (p <.001). A significant increasing temporal trend was registered for PLWH. Over a cumulative follow up of 2,554 years, 293 incident infections were registered with an IR of 11.5 per 100PYFU. Departments showed diverse IRs: 7.9 per 100PYFU for PLWH, 30.1 per 100PYFU for PrEP users, 22.7 per 100PYFU for STI clinic. Poisson regression model found a significant increase in incident rates over time in the overall study population driven by PLWH and PrEP users. Conclusions: MG is uncommon in the general population with stable trends, while PLWH and PrEP users exhibit increasing positivity rate and incidence.