Morphological changes in the testicle in "Sertoli cell only" syndrome in men with non-obstructive azoospermia

BACKGROUND: The relevance of morphological studying of testicular biopsies in infertile men is explained by the small amount of information and research in this area, which is associated with limited indications for obtaining a lifetime biopsy in this disease. AIM: To evaluate morphological changes in the testicle in Sertoli cell-only syndrome (SCOS). MATERIALS AND METHODS: Using staining of sections with hematoxylin and eosin, toluidine blue, a morphological assessment of convoluted seminal tubules with SCOS was performed using light microscopy in 9 men with non-obstructive azoospermia. RESULTS: Mature Sertoli cells were found in 48.2% of convoluted seminal tubules, Sertoli cells with signs of dystrophy were in 33.6% of seminal tubules, Sertoli cells with signs of apoptosis were found in 18.2% of seminal tubules. The average number of Sertoli cells in one convoluted seminal tubule was 15.4±6.1. The diameter of the convoluted seminal tubule was on average 33.8±9.6 microns. The thickness of the shell of the convoluted seminal tubule in SCOS was on average 0.63 ± 0.18 microns. The number of mast cells in the testicular interstitium was on average 8.5±0.3 per 1 mm2. The relationship between the thickness of the shell of the convoluted seminal tubule and the number of Sertoli cells was strong and inverse (r=-0.87). The relationship between the thickness of the membrane of the convoluted seminal tubule and the number of mast cells in the testicular interstitium was strong and direct (r=0.83). CONCLUSIONS: SCOS occurs in 47.3% of patients with non-obstructive azoospermia. An increase in the thickness of the shell of the convoluted seminal tubule contributes to a violation of the architectonics of the hematotesticular barrier. This study showed that mast cells have a direct effect on the wall thickness of the convoluted seminal tubule, which demonstrates the possible pathological effect of these cells on the permeability of the hematotesticular barrier and impaired spermatogenesis.