Splenogonadal Fusion : Pathogenesis

Pathogenesis of Splenogonadal Fusion: The pathogenesis is not clearly understood but thought to be a field defect resulting in abnormal migration of spleen cells between 5th and 8th week of embryonic development when the spleen and the gonads are close to each other. When the gonad descends in later stages, the attached splenic tissue follows with it. Rarely, spleen may be fused with kidney (splenorenal fusion) or liver (splenohepatic fusion).

This image of a cryptorchid testis from a case of splenogonadal fusion shows atrophic seminiferous tubules with thickened basement membranes and Sertoli cells. A few clusters of Leydig cells are also present.