Doctoral defence: Stanislav Tjagur "Mycoplasma genitalium and other sexually transmitted infections causing urethritis – their prevalence, impact on male fertility parameters and prostate health"

On 15 September at 12:00 Stanislav Tjagur will defend his doctoral thesis "Mycoplasma genitalium and other sexually transmitted infections causing urethritis – their prevalence, impact on male fertility parameters and prostate health" for obtaining the degree of Doctor of Philosophy (in Medicine).

Supervisors:
Professor Margus Punab, University of Tartu
Professor Reet Mändar, University of Tartu 

Opponent:
Professor Florian Wagenlehner, University Hospital Giessen (Germany)

Summary
Function of urethra is the transportation of seminal fluid and urine. At the same time, urethra can be an entrance point for urethritis-associated sexually transmitted pathogens. Urethritis can result in impairment of reproductive function but the evidence about this topic is uneven. Novel diagnostic technique of urethritis, flow-cytometric analysis, is not validated. Until now, there was no clear etiological picture of male urethritis in Estonia.  

Aim of the study was to reveal the prevalence of urethritis among different populations in Estonia, its impact on male urogenital system, association between different STI agents (Neisseria gonorrhoeae, Chlamydia trachomatis, Mycoplasma genitalium, Trichomonas vaginalis) and patients’ complaints, symptoms & inflammatory parameters, and the applicability of flow-cytometric analysis for urethritis patients. The study included 3571 male patients from Centre of Andrology, Tartu University Hospital.   

Chlamydia had the highest prevalence among Estonian men with high-risk sexual behaviour (14.8%) but M. genitalium held an important second place (4.2%). N. gonorrhoeae (2.5%), T. vaginalis (0.7%) and combined STIs (1.5%) were detected less frequently. Prevalence of STIs among male partners of pregnant women (C. trachomatis 1.6%) and male partners of infertile couples (C. trachomatis 1.2%, M. genitalium 1.1%) was low. Neither of the macroscopic signs of urethritis was pathognomonic for any particular disease or STI agent, therefore, patient’s sexual behaviour patterns should also be accounted for when making decision about STI testing. 

Flow cytometry of first-voided urine appeared to be a rapid and objective screening method in case of suspected male urethritis. N. gonorrhoeae did provoke the strongest inflammatory reaction in first-voided urine, M. genitalium and C. trachomatis did induce moderate inflammation, while in case of T. vaginalis the inflammatory reaction was weak. M. genitalium provoked inflammatory reaction in semen, too, but in most cases far below the WHOs proposed limit. This limit should be lowered in order to find out more patients who need treatment. 

M. genitalium and C. trachomatis possessed negative impact on semen parameters, including total count of spermatozoa and count of spermatozoa with progressive motility. Thus, the potential impact of these pathogens on male fertility requires further investigations.

Defence can be also followed in Teams.