Detection of chlamydia infection within human testicular biopsies

Abstract

STUDY QUESTIONCan Chlamydia be found in the testes of infertile men?SUMMARY ANSWERChlamydia can be found in 16.7% of fresh testicular biopsies and 45.3% of fixed testicular biopsies taken from a selection of infertile men.WHAT IS KNOWN ALREADYMale chlamydial infection has been understudied despite male and female infections occurring at similar rates. This is particularly true of asymptomatic infections, which occur in 50% of cases. Chlamydial infection has also been associated with increased sperm DNA damage and reduced male fertility.STUDY DESIGN, SIZE, DURATIONWe collected diagnostic (fixed, n = 100) and therapeutic (fresh, n = 18) human testicular biopsies during sperm recovery procedures from moderately to severely infertile men in a cross-sectional approach to sampling.PARTICIPANTS/MATERIALS, SETTING, METHODSThe diagnostic and therapeutic biopsies were tested for Chlamydia-specific DNA and protein, using real-time PCR and immunohistochemical approaches, respectively. Serum samples matched to the fresh biopsies were also assayed for the presence of Chlamydia-specific antibodies using immunoblotting techniques.MAIN RESULTS AND THE ROLE OF CHANCEChlamydial major outer membrane protein was detected in fixed biopsies at a rate of 45.3%. This was confirmed by detection of chlamydial DNA and TC0500 protein (replication marker). C. trachomatis DNA was detected in fresh biopsies at a rate of 16.7%, and the sera from each of these three positive patients contained C. trachomatis-specific antibodies. Overall, C. trachomatis-specific antibodies were detected in 72.2% of the serum samples from the patients providing fresh biopsies, although none of the patients were symptomatic nor had they reported a previous sexually transmitted infection diagnosis including Chlamydia.LIMITATIONS, REASONS FOR CAUTIONNo reproductively healthy male testicular biopsies were tested for the presence of Chlamydia DNA or proteins or Chlamydia-specific antibodies due to the unavailability of these samples.WIDER IMPLICATIONS FOR THE FINDINGSApplication of Chlamydia-specific PCR and immunohistochemistry in this human male infertility context of testicular biopsies reveals evidence of a high prevalence of previously unrecognised infection, which may potentially have a pathogenic role in spermatogenic failure.STUDY FUNDING/COMPETING INTEREST(S)Funding for this project was provided by the Australian NHMRC under project grant number APP1062198. We also acknowledge assistance from the Monash IVF Group and Queensland Fertility Group in the collection of fresh biopsies, and the Monash Health and co-author McLachlan (declared equity interest) in retrieval and sectioning of fixed biopsies. E.M. declares an equity interest in the study due to financing of fixed biopsy sectioning. All other authors declare no conflicts of interest.TRIAL REGISTRATION NUMBERN/A

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

“…Although CT is responsible for 40%-60% of nongonococcal urethritis, 15%-56% of chronic prostatitis and 20%-50% of acute epididymitis (Cunningham & Beagley, 2008;López-Hurtado, Velazco, et al, 2018), their participation in male infertility remains controversial. This is due to the fact that the semen quality of those who are gen by experimental infection using CT (Bryan et al, 2019;Filardo et al, 2019).…”

“…In spite of the above, in this study, the concordant couples that showed tubal occlusion [3.19 (95% CI 1.09–9.34), p < .05] presented significant alterations in the number of spermatozoon and semen volume. Alterations in sperm count may be due to infection of the seminiferous tubules and Sertoli cells, as Bryan et al recently demonstrated the detection of CT in testicular biopsies among men with severe and moderate infertility or according to results of Filardo et al who demonstrated the susceptibility of human Sertoli cells to this pathogen by experimental infection using CT (Bryan et al., 2019; Filardo et al., 2019).…”

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“…In general, the genital tract is prone to the growth of pathogenic and non-pathogenic microorganisms. Numerous studies have shown that semen bacterial infections may adversely affect male reproductive health, which in turn leads to the reduction of male fertility (1,5).…”