Postnatal testicular maldevelopment in unilateral cryptorchidism

Area of Science:

• Reproductive Endocrinology
• Pediatric Urology
• Histopathology

Background:

• Cryptorchidism, or undescended testes, is a common congenital condition associated with male infertility.
• The contralateral descended testis in cases of unilateral cryptorchidism often exhibits subtle abnormalities.
• Understanding the testicular histology in cryptorchidism is crucial for elucidating the mechanisms of infertility.

Purpose of the Study:

• To perform a histomorphometric analysis of unilaterally cryptorchid testes and their descended partners.
• To investigate the developmental abnormalities of germ cells and Leydig cells in cryptorchidism.
• To explore the potential link between testicular histology and hypogonadotropic hypogonadism in cryptorchidism.

Main Methods:

• Histomorphometric analysis of semi-thin sections.
• Examination of testicular biopsies from 232 unilaterally cryptorchid testes.
• Comparison with 195 contralateral descended testes.

Main Results:

• A reduced number of germ cells was observed from the first year of life.
• Delayed or defective transformation of gonocytes to Ad spermatogonia and Ad spermatogonia to primary spermatocytes occurred.
• Decreased numbers of Leydig cells were noted in both cryptorchid and descended testes, with greater severity in the cryptorchid testes.

Conclusions:

• Testicular abnormalities, including germ cell and Leydig cell deficiencies, are present in both cryptorchid and contralateral testes.
• These abnormalities are more severe, earlier in onset, and more progressive in the cryptorchid testes.
• Findings support the hypothesis that hypogonadotropic hypogonadism contributes to the infertility associated with unilateral cryptorchidism.