Concretions in the human testis are derived from the basal lamina of seminiferous cords

Area of Science:

• Reproductive Biology
• Histopathology
• Cell Biology

Background:

• Testicular concretions are observed in association with seminiferous cords.
• Seminiferous cords in affected testes exhibit hypoplastic zones with immature Sertoli cells, thick basal laminae, and myofibroblasts.
• These cords form coiled, ring-like structures.

Purpose of the Study:

• To investigate the origin and composition of testicular concretions.
• To elucidate the relationship between testicular concretions and seminiferous cord structure.
• To determine the potential diagnostic significance of testicular concretions.

Main Methods:

• Light and electron microscopy of testicular tissue from 6 patients.
• Computer-assisted 3-D reconstructions of seminiferous cords using serial semithin sections.

Main Results:

• Testicular concretions are accumulations of basal lamina material, sometimes containing degenerated myofibroblast remnants.
• Concretions form outside the seminiferous cords, within the connective tissue compartment.
• They communicate with interstitial tissue via openings and are enveloped by Sertoli cells or myofibroblasts.

Conclusions:

• Testicular concretion formation is linked to a disturbance in the interaction between Sertoli cells and myofibroblasts.
• The presence of testicular concretions may indicate a developmental disorder and defective seminiferous cords.
• Concretions are proposed to be pathognomonic for defective seminiferous cords.