RESUMO
BACKGROUND: Male infertility is caused by genetic anomalies in 15-30% of cases. This study aimed to determine stereological properties of seminiferous tubules in infertile men with genetic anomalies, including Klinefelter Syndrome (KS), Y chromosome microdeletions (MYC) and CFTR gene mutations (CFTR); and to compare them to seminiferous tubules of men with obstructive azoospermia of non-genetic origin (control group). METHODS: The study was conducted on 28 human testis biopsy specimens obtained from 14 patients with MYC, 18 samples from 9 patients with KS, and 6 samples from 3 patients with CFTR. Whenever possible, a bilateral biopsy was included in the study. The control group had 33 samples from 18 patients (3 of them with a solitary testis). Qualitative and quantitative (stereological) analysis of seminiferous tubules (including the status of spermatogenesis, volume, surface area, length and number of tubules) were performed in all groups. RESULTS: Qualitative histological analysis revealed significant impairment of spermatogenesis in KS and MYC, whereas testicular parenchyma was fully maintained in CFTR and control groups. Spermatogenesis was most seriously impaired in KS. All stereological parameters were significantly lower in KS and MYC, compared to the CFTR and control groups. The total volume, surface and length of seminiferous tubules were significantly lower in KS compared with MYC. CONCLUSIONS: Stereological analysis is valuable in evaluating male infertility, whereas qualitative histological analysis can be helpful in assessing sperm presence in testicular tissue of patients with KS or MYK undergoing TESE.