Asymptomatic bacteriospermia and infertility—what is the connection?

Abstract

Objective To determine the impact of asymptomatic bacteriospermia on semen quality in subfertile men. Methods We conducted a retrospective, single-centre cohort study in 1300 subfertile men. In those diagnosed with asymptomatic bacteriospermia we performed univariate and multivariate logistic regression models to evaluate the strain-specific association with semen parameters. Results Asymptomatic bacteriospermia was diagnosed in 3.2% of patients. The microbiological semen analysis revealed a poly-microbial result in 60%. The most common bacterial species were coagulase-negative Staphylococci species (71.4%), Streptococcus viridans (50.0%) and Enterococcus faecalis (26.2%). Sexually transmitted pathogens were identified in 11.9% of semen samples. The detection of Streptococcus viridians or Haemophilus parainfluenzae correlated with impaired sperm morphology (p < 0.05). The presence of coagulase-negative Staphylococci species or Enterococcus faecalis was associated with pathological low counts of live spermatozoa (p < 0.05). In multivariate analysis only Enterococcus faecalis showed a significant impact on sperm concentration (OR 4.48; 95% CI 1.06–22.10; p = 0.041). Conclusions Asymptomatic bacteriospermia has always been a subject of great controversy. There is still an ongoing debate whether to treat or not to treat. Here, we demonstrate that asymptomatic bacteriospermia is clearly associated with impaired semen quality. Our findings speak in favour of strain-specific interactions with semen parameters. Especially Enterococcus faecalis seriously affects sperm concentration.

Possible Implications of Bacteriospermia on the Sperm Quality, Oxidative Characteristics, and Seminal Cytokine Network in Normozoospermic Men

“…As postulated by Fraczek and Kurpisz [ 3 ], leukocytes are paramount in the surveillance and phagocytosis of abnormal and/or dead spermatozoa; nevertheless, their inappropriate activation ignited by a tight adherence to male gametes leads to phagocytosis, even of viable and morphologically normal spermatozoa [ 1 , 3 , 46 , 47 ]. While the negative impact of leukocytospermia on conventional sperm parameters has been previously established in patients suffering from urogenital infections [ 2 , 48 , 49 , 50 ], our results emphasize on the fact that the presence of particularly coliform bacteria in semen may be accompanied by a rise of leukocyte levels with a subsequent damage particularly to the sperm membranous structures, even in normozoospermic men. This is in agreement with Fraczek et al [ 7 ], according to who bacteria alongside with leukocytes compromised the lipid symmetry of the sperm membranes in healthy young males, leading to a distortion in the plasma membrane integrity.…”

Indokolt-e a spermaminták bakteriológiai szűrése in vitro fertilizáció előtt?

“…Ehhez hasonlóan számos más kutatócsoport sem talált eltérést bacteriospermia esetén a sperma minőségi paramétereiben [31,32]. Ellentétes eredményre jutott egy 2022. évi vizsgálat, mely bacteriospermia jelenlétében sziginifikánsan csökkent spermiummotilitást talált normálmorfológia mellett [33]. De Francesco és mtsai bacteriospermia esetében szignifikánsan alacsonyabb spermiumkoncentrációt és -mozgékonyságot mértek, bár a paraméterek a WHO kritériumai szerint még így is a normáltartományba estek.…”

Impact of Microbial Infection on Sperm Parameters of Seminal Bacteria in Asymptomatic Subfertile Males

“…This sperm-bacterial agglutination causes the production of a biofilm that can accommodate more vulnerable surroundings for further bacterial colonization [9]. The impact of seminal bacteria on semen quality has not been fully exposed, and it is unclear if seminal bacterial infection in asymptomatic males is associated with male subfertility [10]. Moreover, the bacterial species-specific impacts on sperm parameters and related antibiotic treatment needs in asymptomatic males are controversial [11].…”