Risk of HIV acquisition among men who have sex with men infected with bacterial sexually transmitted infections: A systematic review and meta-analysis.

Background Men who have sex with men (MSM) who have bacterial sexually transmitted infections (STIs) are at increased risk for HIV infection. We enhanced and updated past summary risk estimates. Methods We systematically reviewed (PROSPERO #CRD42018084299) peer-reviewed studies assessing risk of HIV infection among MSM attributable to: Chlamydia trachomatis (CT), Mycoplasma genitalium (MG), Neisseria gonorrhoeae (NG), Treponema pallidum (TP), and/or Trichomonas vaginalis (TV). We searched three databases through December 2017. We excluded studies with self-reported data or simultaneous STI and HIV assessment. We conducted dual screening and data extraction, meta-analytically pooled risk ratios (RR), and assessed potential risk of bias. Results We included 26 studies yielding 39 RR (k) for HIV acquisition due to one of TP, NG, or CT. We did not identify eligible data for MG or TV nor for HIV transmission. HIV acquisition risk increased among MSM infected with TP (k=21, RR 2.68, 95% CI 2.00-3.58), NG (k=11, RR 2.38, 95% CI 1.56-3.61), and CT (k=7, RR 1.99, 95% CI 1.59-2.48). Sub-analysis RR for all three pathogens were >= 1.66 and remained statistically significant across geography and methodological characteristics. Pooled RR increased for data with the lowest risk of bias for NG (k=3, RR 5.49, 95% CI 1.11-27.05) and TP (k=4, RR 4.32, 95% CI 2.20-8.51). We observed mostly moderate to high heterogeneity and moderate to high risk of bias. Conclusion MSM infected with TP, NG, or CT have twice or greater risk of HIV acquisition, although uncertainties exist due to data heterogeneity and risk of bias.