Background Sexually transmissible infections (STIs) have been increasing in men who have sex with men (MSM) in recent years; however, few studies have investigated the prevalence or antimicrobial resistance in rectal Mycoplasma genitalium in this group. This study aimed to determine the prevalence and predictors of rectal M. genitalium in MSM attending an urban sexual health service in Sydney, Australia, namely the Sydney Sexual Health Centre (SSHC), as well as estimate the rate of macrolide resistance. Methods: A prospective cross-sectional analysis was conducted of rectally asymptomatic MSM having a rectal swab collected as part of their routine care. Participants self-collected a rectal swab to be tested for M. genitalium and completed a 14-item questionnaire that provided information on behavioural risk factors. The prevalence of rectal M. genitalium was determined and multivariate analysis was performed to assess the associations for this infection. Positive specimens then underwent testing for macrolide-resistant mutations (MRMs) using the ResistancePlus MG assay (SpeeDx, Eveleigh, NSW, Australia). Results: In all, 742 patients were consecutively enrolled in the study. The median age was 31 years (interquartile range 27–39 years), with 43.0% born in Australia. Overall, 19.0% of men were bisexual, 22.9% were taking pre-exposure prophylaxis (PrEP) and 4.3% were HIV positive. The prevalence of rectal M. genitalium was 7.0% (95% confidence interval (CI) 5.3–9.1) overall and 11.8% in those taking PrEP. On multivariate analysis, PrEP use was significantly associated with having rectal M. genitalium (odds ratio 2.01; 95% CI 1.09–3.73; P = 0.01). MRMs were detected in 75.0% (36/48; 95% CI 60.4–86.4%) of infections. Conclusion: Rates of rectal M. genitalium infection were high among asymptomatic MSM attending SSHC and MRMs were detected in 75% of infections. PrEP use was found to be significantly associated with rectal M. genitalium infection. These data contribute to the evidence base for screening guidelines in MSM.

Objectives: Mycoplasma genitalium (M. genitalium) is a sexually transmitted infection of importance because of the high prevalence rates and antimicrobial resistance (AMR) among men who have sex with men (MSM).Methods: A prospective cross-sectional analysis was carried out on MSM who presented rectally asymptomatic at a central Sydney sexual health clinic or a community site for routine testing. Between March and May 2017, participants were asked to complete a questionnaire before testing. We used multivariable logistic regression to identify factors associated with awareness and concern toward M. genitalium and AMR.Results: Overall, 692 (92.5%) of 746 (95% confidence interval [CI], 90.7-94.5) MSM had no prior awareness of M. genitalium; 512 (68.6%) of 746 (95% CI, 65.2-72.0) were not concerned or were neutral about the infection; and 234 (31.4%) of 746 (95% CI, 28.0-34.8) were a little, somewhat, or very concerned. High partner numbers (adjusted odds ratio [AOR], 4.2; 95% CI, 2.1-8.2) and inconsistent condom users (AOR, 3.1; 95% CI, 1.2-8.2) and no condoms used (AOR, 3.9; 95% CI, 1.2-12.6) were associated with awareness of the infection. Time since arrival in Australia of more than 10 years (AOR, 1.73; 95% CI, 1.09-2.75), more than 12 months (AOR, 1.91; 95% CI, 1.31-2.79), and recreational drug use (AOR, 1.95; 95% CI, 1.17-3.24) were associated with concern around having M. genitalium. Overall, 61.6% (458/744; 95% CI, 58.2-65.3) MSM reported that they would increase condom use (38.6% agreed and 23.1% strongly agreed) after reading about AMR. Among the remaining 38.4% (286/ 744), 28.4% indicated a neutral response to increasing their condom use. Relative to MSM born in Australia, Latin American (AOR, 7.3; 95% CI, 2.9-18.4) or Asian MSM (AOR, 2.3; 95% CI, 1.4-3.3), were significantly more likely to increase condom use after reading a statement on AMR.Conclusions: Knowledge of M. genitalium remains low among MSM.Targeted messages using AMR and treatment difficulties with M. genitalium is unlikely to change behavior for a large proportion of MSM.