Prevalence of <i>Mycoplasma genitalium</i> and other sexually transmitted infections causing urethritis among high-risk heterosexual male patients in Estonia

<b>Background:</b> We aimed to evaluate the prevalence of sexually transmitted infections (STI, including <i>Mycoplasma genitalium</i>, <i>Chlamydia trachomatis</i>, <i>Neisseria gonorrhoeae</i>, <i>Trichomonas vaginalis</i>) among high-risk heterosexual male patients and to clarify their potency to cause complaints and inflammation. <b>Methods:</b> The study group included 825 men (18.0–49.5 y) consulting andrologist at Tartu University Hospital (Estonia) due to subjectively perceived risk of STI. Patients completed STI risk behaviour questionnaire. First voided urine was analysed for white blood cells and STIs. <b>Results:</b> In total 193 (23.4%) patients were positive for one or multiple STI. The prevalence of <i>C. trachomatis</i>, <i>M. genitalium</i>, <i>N. gonorrhoeae</i>, <i>T. vaginalis</i> and combined STI was 14.3%, 4.4%, 2.7%, 0.7% and 1.3%, respectively. <i>N. gonorrhoeae</i> had the highest potency to generate inflammatory reaction in first voided urine (100%) followed by <i>C. trachomatis</i> (72.0%), <i>M. genitalium</i> (63.9%) and <i>T. vaginalis</i> (33.3%). <i>N. gonorrhoeae</i> and <i>T. vaginalis</i> caused the highest mean number of complaints while half of <i>T. vaginalis</i> cases and nearly fifth of <i>M. genitalium</i> and <i>C. trachomatis</i> cases were asymptomatic. <b>Conclusions:</b><i>C. trachomatis</i> has the highest prevalence among Estonian high-risk men but <i>M. genitalium</i> holds an important second place. Prevalence of combined STIs is low. <i>N. gonorrhoeae</i> has the highest potency to generate urethral inflammation followed by <i>C. trachomatis</i> and <i>M. genitalium</i>. The highest number of complaints is also associated with <i>N. gonorrhoeae</i> while half of <i>T. vaginalis</i> cases and nearly a fifth of <i>M. genitalium</i> and <i>C. trachomatis</i> cases are asymptomatic.