Pattern of Sertoli cell degeneration in cryptorchid prepubertal tests

Abstract

Seventy‐three testicular biopsies from 54 children (aged 2 months‐14 years) with undescended testes were examined by light and electron microscopy. The biopsies included abdominal, inguinally fixed, inguinally moveable, and retractile testesl. Alterations in Sertoli cell morphology were found in all biopsies. The alterations included dilated elements of rough endoplasmic reticulum, vacuolization of the cytoplasm, mitochondria with poorly preserved cristae, increase in electron density of the matrix, elongation of the nuclei, and irregularities of the nuclear membrance. According to the numerical appearance of these cells and to the extent of lesions in single Sertoli cells, seven phases in the contionuous process of tubular alteration were distinguished. The most severe tubular damaged (phase VII> occurred when the seminiferous epithelium consisted exclusively of necrotic cells. All phases of tubular alterations were seen regularly in each of the biopsies investigated. Germ cells occurred only in phases I‐IV and were never observed in tubules in phases V‐VII. Significant differences became evident between inguinal and retractile tests by morphometric evaluation. It was demonstrated that the number of germcells per cross‐sectioned tubule (S/T value) correlated negatively with the percentage of tubules in phases V‐VII. In contrast to inguinal testes, a complete absence of Sertoli cells and an S/T value <0.1 were never found in retractile tests and the percentage of tubules in phases V‐VII was reduced signficantly compared with inguinal testes. Our findings indicate that (i) maldescended testis in patients between 1 and 15 years‐of‐age is associated with a special pattern of Sertoli cell degeneratlion; (ii) Sertoli cell degeneration is a continuous process, which can lead eventually to complete dissolution of the seminiferous epithelium; (ii) total degeneration is not related to age but is dependent on testicular pposition; (iv) a defined phase of degeneration excludes germ cell development, and therefore enhanced Sertoli cell degeneration in cryptorchid tests must also account for the reduction in germ cell number. Copyright © 1992, Wiley Blackwell. All rights reserved