The effect of seminal pathogens on standard semen parameters, sperm kinematics and seminal inflammatory markers

This study evaluated the effects of urogenital pathogens on standard semen parameters, sperm kinematics and host inflammatory response in a cohort of asymptomatic subfertile men. There were six groups based on the results of bacterial culture, including Ureaplasma urealyticum (U. Urealyticum) (n = 27), mixed comprising two or more pathogenic species (n = 28), Gardnerella Vaginalis (G. Vaginalis) (n = 15), gram-positive cocci and bacilli (g+cocci/bacilli) (n = 15), gram-negative bacilli (g-bacilli) (n = 10) and Chlamydia trachomatis (C. trachomatis) (n = 2). One control group (n = 20) and one leukocytospermic group (n = 10) were also included. Sperm quality parameters, seminal leukocytes and interleukin (IL)-6 of all groups, apart from C. trachomatis, were compared to the control group. Standard semen parameters were significantly worse in all groups except for that with g-bacilli. Progressive motility, total motility and normal sperm morphology demonstrated the most significant differences, when U. Urealyticum, leukocytospermia and mixed pathogens were detected in semen. Among sperm kinematics, the concentration of progressive motile sperm cells (CPMS), the percentage of progressive motile sperm cells (PPMS) and straightness (STR) were manifested significant declines in the presence of seminal pathogens. CPMS was affected in all groups except for G. vaginalis. Moreover, the presence of g+cocci/bacilli and g-bacilli were associated with increased seminal IL-6. Seminal leukocytes were elevated significantly only when g-bacilli were cultured in semen. We conclude that seminal pathogens can negatively affect sperm quality. The most negative effect is related to U. Urealyticum. Moreover, g+cocci/bacilli and g-bacilli can initiate an inflammatory response.