The prevalence of urethral and rectal Mycoplasma genitalium and its associations in men who have sex with men attending a genitourinary medicine clinic

Objectives To determine the prevalence of rectal and urethral Mycoplasma genitalium (MG) in men who have sex with men (MSM) attending a genitourinary medicine clinic and to measure its associations with symptoms, clinical signs, sexual behaviour and concomitant sexually transmitted infections (STI). Methods MSM attending for STI screening were tested for MG using a real-time PCR assay that targets the MgPa gene. Data were collected on demographics, sexual behaviour, past STI history and clinical symptoms and signs. Results 849 first-void urine and rectal specimens were collected from 438 MSM. The overall prevalence of MG in MSM was 6.6% with first-void urine positivity of 2.7% and rectal positivity of 4.4%. MG was significantly associated with HIV positivity (OR 7.6, 95% CI 3.2 to 18.7, p < 0.001) in contrast to Chlamydia trachomatis (OR 1.5, 95% CI 0.5 to 4.1, p=0.4) and Neisseria gonorrhoeae (OR 1.7, 95% CI 0.7 to 3.8, p=0.194). MG was more prevalent than C trachomatis (p=0.15) and N gonorrhoeae (p=0.02) in this subgroup of HIV-positive MSM. Urethral infection was associated with dysuria (p < 0.001) but there was no association between rectal infection and anorectal symptoms or signs. Conclusion Rates of MG are much higher in HIV-positive MSM than HIV-negative MSM at both urethral and rectal sites, and MG is more prevalent in HIV-positive MSM than other bacterial STI. Although the subclinical nature of MG in the rectum questions its significance, the high prevalence seen at this site could be a potential source of onward urethral transmission. Future work should assess the need for appropriate screening and treatment of MG infection in MSM, particularly those with HIV infection and high-risk sexual behaviour.