Prevalence and correlates of Mycoplasma genitalium infection among prostatitis patients in Shanghai, China

Background: Mycoplasma genitalium (M. genitalium) has been shown to be involved in chronic non-gonococcal urethritis (NGU). However, the prevalence and determinants of this emerging sexually transmissible infection among prostatitis patients remain obscure. Methods: Two hundred and thirty-five patients diagnosed with prostatitis and 152 health controls from sexually transmitted diseases (STD) clinics in Shanghai, China, were selected. M. genitalium was detected in the initial voided urine (VB1), midstream of urine (VB2), expressed prostatic secretion (EPS) and the opening urine after massage (VB3) by quantitative polymerase chain reaction (Q-PCR) targeting the Mycoplasma genitalium adhesion protein (MgPa). An infection of the prostate was considered positive if a uropathogen was found only in the EPS sample or VB3, or if it was at least four-fold greater in EPS or VB3 than in VB1 or VB2. The prostatitis patients with M. genitalium infection were treated with azithromycin. Results: The prevalence of M. genitalium infection was significantly higher among the prostatitis group than the control group (10 vs 3%, P≤0.005). Among the prostatitis group, M. genitalium infection was significantly associated with those patients who received treatment for genitourinary infection previously than those patients who did not (17 vs 6%; adjusted OR, 4.011; 95% CI, 1.562-10.300). The symptoms were totally or partially improved in 83% per cent (19/23) of prostatitis patients with M. genitalium, positive in EPS and M. genitalium turned negative after azithromycin treatment. Conclusions: M. genitalium was prevalent in the patients with prostatitis, particularly in those who received ineffective antibiotic treatment for the bacterium, and was identified as having a significant association of prostatitis.