Bacterial vaginosis-associated bacteria in cisgender men who have sex with women: prevalence, association with non-gonococcal urethritis and natural history

Abstract

ObjectivesBacterial vaginosis-associated bacterium 2 (BVAB2),Mageeibacillus indolicusandSneathiaspp are highly predictive of bacterial vaginosis (BV) in cisgender women. They have been associated with non-gonococcal urethritis (NGU) in cisgender men in some but not all populations. We evaluated this association in a cross-sectional study of cisgender men who have sex with women only (MSW).MethodsMSW without gonorrhoea attending a sexual health clinic (SHC) from 2014 to 2018 completed a computer-assisted self-interview, clinical interview and examination. NGU was defined as ≥5 polymorphonuclear leucocytes/high-power field in urethral exudates plus either urethral symptoms or visible discharge. Urine was tested forChlamydia trachomatisandMycoplasma genitaliumusing Aptima (Hologic) and for BVAB2,M. indolicus,Sneathiaspp,Trichomonas vaginalis,Ureaplasma urealyticum,Haemophilus influenzae, herpes simplex virus and adenovirus using quantitative PCR.ResultsOf 317 MSW age 17–71, 67 (21.1%) hadSneathiaspp, 36 (11.4%) had BVAB2, and 17 (5.4%) hadM. indolicusat enrolment. Having ≥3 partners in the past 2 months was the only characteristic that was more common among MSW with than those without these bacteria (BVAB2: 47% vs 23%,M. indolicus: 53% vs 24%,Sneathiaspp: 42% vs 22%; p≤0.03 for all). One-hundred seventeen men (37%) were diagnosed with NGU at enrolment. There was no significant association of BVAB2,M. indolicusorSneathiaspp with NGU (adjusted OR=0.59, 95% CI 0.14 to 2.43; aOR=3.40, 95% CI 0.68 to 17.06; aOR=0.46, 95% CI 0.16 to 1.27). Of 109 MSW with monthly samples, 34 (31.2%) had one of the bacteria at one or more follow-up visits, 22 of which were co-colonised with >1. Median persistence over 6 months did not differ significantly (BVAB2=30.5 days, IQR=28–87;M. indolicus=87 days, IQR=60–126;Sneathiaspp=70 days, IQR=30–135; p≥0.20 for each comparison).ConclusionsNeither BVAB2,M. indolicusnorSneathiaspp were associated with increased risk of prevalent NGU in MSW attending an SHC.