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Infectious Burden and Semen Parameters
Elena Moretti1, Natale Figura2, Maria Stella Campagna2
1Department of Molecular and Developmental Medicine, University of Siena, Siena, Italy.
Insights
Chronic infections negatively impact male fertility. Increased pathogen burden, indicated by immunoglobulin G response, significantly reduces sperm concentration, motility, and quality, increasing sperm necrosis.
Area of Science:
- Reproductive Medicine
- Infectious Diseases
- Immunology
Background:
- Pathogen burden, the cumulative effect of chronic infections, is linked to adverse health outcomes.
- Previous research suggests Helicobacter pylori infection may impair semen quality.
- Understanding the impact of multiple chronic infections on male reproductive health is crucial.
Purpose of the Study:
- To investigate the association between chronic infections detected via serum markers and semen quality.
- To evaluate the relationship between pathogen burden and specific semen parameters.
Main Methods:
- Collected blood and semen samples from 73 men between January 2014 and January 2015.
- Assessed semen characteristics using light and transmission electron microscopy, quantifying parameters like fertility index (FI) and sperm apoptosis/necrosis.
- Detected immunoglobulin G (IgG) antibodies against common chronic infection agents (H. pylori, M. pneumoniae, C. pneumoniae, EBV, HSV-1, CMV) using ELISA.
Main Results:
- High prevalence of infections detected: EBV (95.9%), HSV-1 (74.0%), M. pneumoniae (72.6%), C. pneumoniae (46.6%), CMV (46.6%), H. pylori (43.8%).
- Increased number of pathogens with a significant IgG response correlated with reduced sperm concentration (P<.05), motility (P<.001), and fertility index (P<.001).
- A higher pathogen burden was significantly associated with an increased percentage of necrotic sperm (P<.01).
Conclusions:
- A higher number of pathogens eliciting a systemic IgG response is associated with diminished semen quality.
- Pathogen burden represents a significant factor impacting male fertility.
Objective:
To investigate the relationship between chronic infections detected in serum and semen quality. The pathogen burden is a concept consisting in the observation that, in patients with heart disease, damaging effects of the coronary arteries increase concomitantly with the number of agents responsible for chronic infections to which patients mounted a serological response. Previous observations that Helicobacter pylori infection may reduce the semen quality prompted us to perform the present study.
Methods:
Blood and semen samples were collected from 73 selected men, enrolled from January 2014 to January 2015. Semen characteristics were evaluated by light and transmission electron microscopy. Transmission electron microscopy data were quantified with a mathematical formula providing numerical scores, such as fertility index (FI, number of sperm free from ultrastructural defects) and the percentages of sperm apoptosis, immaturity, and necrosis. Serum samples were examined by enzyme-linked immunosorbent assay for the presence of immunoglobulin G to the most common agents of chronic infections such as H. pylori (HP), Mycoplasma pneumoniae (MP), Chlamydophila pneumoniae (CP), Epstein-Barr virus (EBV), herpes simplex virus 1 (HSV-1), and cytomegalovirus (CMV).
Results:
The prevalence of infections was as follows: HP 43.8%, CP 46.6%, MP 72.6%, EBV 95.9%, HSV-1 74.0%, and CMV 46.6%. Concomitantly with the increased number of pathogens against which the patients mounted a significant antibody response, sperm concentration (P <.05), sperm motility (P <.001), and fertility index (P <.001) were significantly reduced and the percentage of necrotic sperm was increased (P <.01).
Conclusion:
The higher the number of pathogens stimulating an immunoglobulin G systemic response, the lower was the semen quality.
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