Molecular detection ofChlamydia trachomatisand semen quality of sexual partners of infertile women

[Infections and male infertility]

BACKGROUND

The role of urogenital infections in male infertility has long been the subject of debate.

METHODS

A bibliographic search limited to English-language literature on human subjects published before 5/2023 resulted in the selection of 189 articles.

RESULTS

Male infertility is often of multifactorial aetiology, and to optimise the prognosis it is important to manage all the factors that can be corrected, including infectious causes, which represent one of the most frequent aetiologies. The infectious agents involved in urogenital infections are most often bacterial or viral, and more rarely parasitic. They can infect the seminal tract, male accessory glands and/or testicles, and usually result in inflammation and increased oxidative stress. These infections reduce male fertility, in particular by altering spermogram parameters and increasing sperm DNA fragmentation. For these reasons, the search for a urogenital infection should be systematic, involving a careful history and clinical examination, ultrasound and systematic bacteriological tests guided by clinical findings. Aetiological treatment may be proposed depending on the picture and the germ involved.

CONCLUSION

This review should help the urologist to establish an accurate diagnosis of the form and extent of the infection, and enable him to define an appropriate therapeutic strategy, tailored to the patient, in order to obtain the best chances of improving male fertility.

The microbiome and male infertility: looking into the past to move forward

The human body harbours trillions of microbes, and their influence on human health has been explored in many parts of the human body, including the male reproductive system. From routine culturing to polymerise chain reaction (PCR) and high throughput DNA sequencing, several studies have identified bacteria in the male reproductive system. In this review, we discuss the past and current literature surrounding the testicular and semen microbiome in correlation with male infertility. We further highlight the potential benefits of probiotics as an alternative therapeutic option for male infertility. Although not conclusive, emerging data are indicating potential implications of certain bacterial members on male fertility. There is a general agreement on the negative impact of some pathogenic bacterial species on semen parameters, including sperm counts, motility, morphology, and DNA integrity. On the other hand, Lactobacillus, known as a human-friendly bacteria, has shown protective effects on semen parameters, which makes it a potentially good probiotic. In order to confirm the findings of previous studies, more clinical studies with larger sample sizes and the right controls are needed.

Identification of Chlamydia trachomatis genotypes in Mexican men with infertile women as sexual partners

BACKGROUND

Chlamydia trachomatis is considered a public health problem due to the high prevalence in sexually active women and men. The distribution of genital Chlamydia genotypes among Mexican men is unknown.

OBJECTIVE

To assess the prevalence of Chlamydia genotypes in men with infertile women as sexual partners.

METHODS

A total of 659 urine samples were collected from men whose sexual partners were infertile women; the identifying Chlamydia infection was by means of a real-time nucleic acid amplification test (qPCR). OmpA gene PCR-RFLP and sequencing were used to confirm the genotypes of C. trachomatis. The association of genotypes with age, spermatic parameters and gynecological data of sexual partners was further analyzed.

RESULTS

Forty-nine urine samples were positive infection (7.4%). The Chlamydia infection was significantly associated with teratozoospermia, azoospermia, hypospermia, and oligozoospermia. Five genotypes (F 51%; 12.2% to D; 12.2% to E; 6.1% to L2 and 4.1% Ia) were correctly identified. None genotypes identified in this comparative study were positively associated with changes in some of the spermatic values because all of them typically produce some considerable damage to these cells.

CONCLUSIONS

The F genotype was the most frequent genotype identified in infertile men from Mexico City and all genotypes play an important role in the seminal alteration of Mexican men whose female partners are infertile.

The effects of Chlamydia trachomatis, Mycoplasma hominis, and Ureaplasma urealyticum loads on semen quality: Detection and quantitative analysis

BACKGROUND

The loads of Chlamydia trachomatis (CT), Mycoplasma hominis (MH), and Ureaplasma urealyticum (UU) may impact infertility, as well as cause risk of transmission. The quality and quantity of semen demonstrate male reproductive health. This study aimed to investigate the semen quality affected by CT, MH, and UU loads.

MATERIALS AND METHODS

130 semen samples, including infertile and fertile cases, were collected and analyzed. The whole genomic DNA was extracted, and the desired genes' plasmids were constructed. The CT, MH, and UU loads were quantified by real-time PCR. The data were analyzed using SPSS version 24.

RESULTS

The average age of participants was 35.2 ± 6.8 years. CT, MH, and UU frequency were 9.2% vs. 3.1%, 15.4% vs. 3.1%, and 15.4 vs. 3.1% in infertile and fertile men, respectively. The mean loads of CT, MH, and UU in infertile men were 6.44 log₁₀ copies/ml (range 5.31-7), 4.24 log₁₀ copies/ml (range 3.37-4.7), and 6.94 log₁₀ copies/ml (range 5.08-8.69) respectively, which was significantly higher than fertile men. The findings revealed a significant correlation between CT and UU loads and semen parameters, whereas the load of MH displayed significant effects just on sperm motility, morphology, and the number of leukocytes.

CONCLUSION

The absence of clinical manifestations may not indicate the quality of semen. The pathogens' loads may significantly influence the quality and properties of male reproductive health.

Chlamydia trachomatis infection in the genital tract is associated with inflammation and hypospermia in the infertile male of China

Chlamydia trachomatis (CT) infection is the most prevalent sexually transmitted bacterial disease worldwide. However, unlike that in female infertility, the role of CT infection in male infertility remains controversial. The objective of this retrospective study was to explore the impacts of CT infection in the genital tract on sperm quality, sperm acrosin activity, antisperm antibody levels, and inflammation in a large cohort of infertile males in China. A total of 7154 semen samples were collected from infertile male subjects, 416 of whom were CT positive (CT+ group) and 6738 of whom were CT negative (CT− group), in our hospital between January 2016 and December 2018. Routine semen parameters (semen volume, pH, sperm concentration, viability, motility, morphology, etc.), granulocyte elastase levels, antisperm antibody levels, and sperm acrosin activity were compared between the CT+ and CT− groups. Our results showed that CT infection was significantly correlated with an abnormally low semen volume, as well as an increased white blood cell count and granulocyte elastase level (all P < 0.05) in the semen of infertile males; other routine semen parameters were not negatively impacted. The antisperm antibody level and sperm acrosin activity were not affected by CT infection. These findings suggested that CT infection might contribute to inflammation and hypospermia but does not impair sperm viability, motility morphology, and acrosin activity or generate antisperm antibodies in the infertile males of China.

Seminal pro-inflammatory cytokines and pH are affected by Chlamydia infection in asymptomatic patients with teratozoospermia

Introduction

Infection and inflammation of the reproductive tract by Chlamydia trachomatis (CT) are recognized as significant risk factors for male infertility. This study aimed to evaluate CT infection and its effects on seminal parameters and cytokines in asymptomatic patients with teratozoospermia.

Material and methods

Semen samples from one hundred four male patients were collected, and CT detection was performed by polymerase chain reaction (PCR). The quality (volume, sperm concentration, pH, motility, morphology, and leucocytes) of the semen was measured by standard procedures recommended by the World Health Organization (WHO). Pro-inflammatory cytokines [interleukin (IL)-1 β, IL-6, IL-8, tumor necrosis factor α (TNF-α), and interferon γ (IFN-γ)], as well as anti-inflammatory cytokines (IL-4, IL-10), were determined by using enzyme-linked immunosorbent assay (ELISA). The frequency of CT infection was expressed as a percentage. Descriptive statistics were used for comparison of cytokines from infertile men, and then the Mann-Whitney U test was applied for the contrast of seminal parameters and cytokines from CT-infected versus non-CT infected men.

Results

A ratio of 33/104 (31.7%) patients were positive for CT infection. The ejaculate of positive CT infection was found to have increased pH (pH = 7.65 in non-CT infected vs. 7.94 CT-infected men; p = 0.026). High levels of pro-inflammatory cytokines were found in the population studied; however, infected males were noted to have high levels of IL-1 β [184.66 (0-3985.33 pg/ml), p = 0.001] and IL-6 [87.8 (0-1042.8 pg/ml), p = 0.001].

Conclusions

CT infection increased seminal pH, as well as IL-1 β and IL-6 cytokines, suggesting a potential role of infection and inflammation in asymptomatic patients with teratozoospermia.

Identification of Chlamydia trachomatis genotypes in Mexican men with infertile women as sexual partners

BACKGROUND

Chlamydia trachomatis is considered a public health problem due to the high prevalence in sexually active women and men. The distribution of genital Chlamydia genotypes among Mexican men is unknown.

OBJECTIVE

To assess the prevalence of Chlamydia genotypes in men with infertile women as sexual partners.

METHODS

A total of 659 urine samples were collected from men whose sexual partners were infertile women; the identifying Chlamydia infection was by means of a real-time nucleic acid amplification test (qPCR). OmpA gene PCR-RFLP and sequencing were used to confirm the genotypes of C. trachomatis. The association of genotypes with age, spermatic parameters and gynecological data of sexual partners was further analyzed.

RESULTS

Forty-nine urine samples were positive infection (7.4%). The Chlamydia infection was significantly associated with teratozoospermia, azoospermia, hypospermia, and oligozoospermia. Five genotypes (F 51%; 12.2% to D; 12.2% to E; 6.1% to L2 and 4.1% Ia) were correctly identified. None genotypes identified in this comparative study were positively associated with changes in some of the spermatic values because all of them typically produce some considerable damage to these cells.

CONCLUSIONS

The F genotype was the most frequent genotype identified in infertile men from Mexico City and all genotypes play an important role in the seminal alteration of Mexican men whose female partners are infertile.

The semen microbiome and its impact on sperm function and male fertility: A systematic review and meta-analysis

BACKGROUND

Male factor is attributable in up to 50% of cases of infertility. In vitro studies demonstrate that bacteria can negatively impact sperm function. The use of next-generation sequencing techniques has provided a better understanding of the human microbiome, and dysbiosis has been reported to impact health. Evidence regarding the impact of the semen microbiome on sperm function and fertility remains conflicting.

MATERIALS AND METHODS

A systematic search was conducted in accordance with the Preferred Reporting Items for Reviews and Meta-analysis (PRISMA) statement. The databases MEDLINE, OVID and PubMed were searched to identify English language studies related to the identification of bacteria in the semen of infertile and fertile men, between 1992 and 2019. Fifty-five observational studies were included, with 51 299 subjects. We included studies identifying bacteria using next-generation sequencing, culture or polymerase chain reaction.

RESULTS

The semen microbiome was rich and diverse in both fertile and infertile men. Three NGS studies reported clustering of the seminal microbiome with a predominant species. Lactobacillus and Prevotella were dominant in respective clusters. Lactobacillus was associated with improvements in semen parameters. Prevotella appeared to exert a negative effect on sperm quality. Bacteriospermia negatively impacted sperm concentration and progressive motility, and DNA fragmentation index (DFI; MD: 3.518, 95% CI: 0.907 to 6.129, P = .008). There was an increased prevalence of ureaplasma urealyticum in infertile men (OR: 2.25, 95% CI: 1.47-3.46). Ureaplasma urealyticum negatively impacted concentration and morphology. There was no difference in the prevalence of chlamydia trachomatis between fertile and infertile men and no significant impact on semen parameters. Enterococcus faecalis negatively impacted total motility, and Mycoplasma hominis negatively impacted concentration, PM and morphology.

DISCUSSION AND CONCLUSIONS

Ureaplasma urealyticum, Enterococcus faecalis, Mycoplasma hominis and Prevotella negatively impact semen parameters, whereas Lactobacillus appears to protect sperm quality. These findings may facilitate the development of novel therapies (eg probiotics), although the evidence regarding the impact of the seminal microbiome on fertility is inconclusive and further studies are needed to investigate this association.

Prevalence, concordance and reproductive sequelae after Chlamydia trachomatis infection in Mexican infertile couples

There are few concordance studies on the Chlamydia trachomatis (infection among infertile couples. The objective of this research was to know the prevalence, concordance and reproductive sequelae that couples may develop when both partners show a C. trachomatis infection. A cross-sectional study among 688 infertile couples using the C. trachomatis detection by real-time PCR was performed. The infertility causes were obtained from their medical records. The prevalence of infection was 8.68%. The percentage of concordance was 22.4% (13 couples). A presence of tubal occlusion was only associated with infected-discordant women [RR = 3.46, 95% CI (1.54-7.74), p < .003]. Seminal values were not associated with discordant men. The concordant couples showed association with the infection and tubal occlusion [RR = 3.19, 95% CI (1.09-9.34), p < .05], and oligozoospermia [RR = 12.17, 95% CI (4.29-34.54), p < .001], hypospermia [RR = 14.13, 95% CI (4.78-41.84), p < .001]. An alteration in semen quality was shown particularly in men whose sexual partners show a tubal pathology. This could occur due to a C. trachomatis infection in the testis, which underlines the need to carry out effective and efficient strategies to identify and treat all sexual partners exposed to C. trachomatis.

[Sexually transmitted infections and male fertility]

BACKGROUND

Sexually transmitted infections (STI) are common worldwide and can cause impairment of fertility. In women pelvic inflammatory disease with subsequent tubal sterility is well-documented but the influence of STI on male fertility is still controversely discussed OBJECTIVE: The effects of various bacterial and viral STI on male fertility are discussed.

MATERIAL AND METHODS

An evaluation of the international literature up to 30 April 2018 was carried out including studies on larger collectives from the Asiatic region.

RESULTS

There is still an inconsistent picture of the influence of various bacterial and viral STI on male fertility. Direct or indirect evidence of the impact of a pathogen alone on the quality of ejaculates could not be clearly demonstrated; however, there are indications of a negative effect by Mycoplasma and Ureaplasma species in large Asiatic collectives. The transmission of viral pathogens, such as human papillomavirus (HPV), herpes simplex virus (HSV) and hepatitis B virus (HBV) possible impairs the success of assisted reproductive techniques. In contrast, manifest inflammatory processes of the male genital tract caused by STI (in particular Chlamydia and gonococci) or human immunodeficiency virus (HIV) infections often result in impairment of sperm qualtity.

CONCLUSION

In cases of male fertility disorders a microbiological clarification is recommended. Further studies on the effect of STI on male fertility in larger collectives are necessary, particularly for Caucasian populations. The utilization of existing preventive measures, such as screening for Chlamydia in young women and HPV vaccination also for young males, should be intensively promoted.

Chlamydiaceae: Diseases in Primary Hosts and Zoonosis

Bacteria of the Chlamydiaceae family are a type of Gram-negative microorganism typified by their obligate intracellular lifestyle. The majority of the members in the Chlamydiaceae family are known pathogenic organisms that primarily infect the host mucosal surfaces in both humans and animals. For instance, Chlamydia trachomatis is a well-known etiological agent for ocular and genital sexually transmitted diseases, while C. pneumoniae has been implicated in community-acquired pneumonia in humans. Other chlamydial species such as C. abortus, C. caviae, C. felis, C. muridarum, C. pecorum, and C. psittaci are important pathogens that are associated with high morbidities in animals. Importantly, some of these animal pathogens have been recognized as zoonotic agents that pose a significant infectious threat to human health through cross-over transmission. The current review provides a succinct recapitulation of the characteristics as well as transmission for the previously established members of the Chlamydiaceae family and a number of other recently described chlamydial organisms.

Immunological Tolerance, Pregnancy, and Preeclampsia: The Roles of Semen Microbes and the Father

Although it is widely considered, in many cases, to involve two separable stages (poor placentation followed by oxidative stress/inflammation), the precise originating causes of preeclampsia (PE) remain elusive. We have previously brought together some of the considerable evidence that a (dormant) microbial component is commonly a significant part of its etiology. However, apart from recognizing, consistent with this view, that the many inflammatory markers of PE are also increased in infection, we had little to say about immunity, whether innate or adaptive. In addition, we focused on the gut, oral and female urinary tract microbiomes as the main sources of the infection. We here marshall further evidence for an infectious component in PE, focusing on the immunological tolerance characteristic of pregnancy, and the well-established fact that increased exposure to the father's semen assists this immunological tolerance. As well as these benefits, however, semen is not sterile, microbial tolerance mechanisms may exist, and we also review the evidence that semen may be responsible for inoculating the developing conceptus (and maybe the placenta) with microbes, not all of which are benign. It is suggested that when they are not, this may be a significant cause of PE. A variety of epidemiological and other evidence is entirely consistent with this, not least correlations between semen infection, infertility and PE. Our view also leads to a series of other, testable predictions. Overall, we argue for a significant paternal role in the development of PE through microbial infection of the mother via insemination.