Cryptorchid testis histopathology in myelomeningocele patients

Cryptorchidism occurs in 25% of boys with myelomeningocele (MMC) compared to 3% of the general population. Testicular biopsy histopathology correlates with future sperm counts. We studied testicular histology in boys with cryptorchidism and MMC to investigate if the MMC influences histological findings.

The study group consisted of six patients with MMC and undescended testis (UDT) who underwent orchiopexy and bilateral testis biopsy. Twelve testicular biopsies from six patients were compared to 40 biopsies from 20 UDT-only controls. Total germ cell count per tubule (TGC/T) and the percentage of adult dark spermatogonia (%Ad) in undescended and contralateral descended testes from the patients were compared with controls.

In the study group, two had total absence of germ cells (TGC/T=0) and three had severely reduced germ cells (TGC/T<0.2). Four had total absence of Ad spermatogonia and the remaining two had severely reduced Ad spermatogonia (%Ad=5). The mean TGC/T and %Ad in patients with UDT and MMC were conspicuously lower than controls. The differences did not reach statistical significance (P=0.09-0.29).

These results suggest that patients with both MMC and UDT have a more severe reduction in total number and more severely delayed maturation of germ cells than do patients with UDT alone. With only six patients in this study, there was not the power to detect statistical significance. In addition to the reproductive problems due to erection and ejaculatory dysfunction in patients with MMC, this severe testicular histopathology may increase the risk of subfertility.