Combined adrenorenal fusion and adrenohepatic adhesion: a case report with review of the literature and discussion of pathogenesis.

The second case of combined adrenorenal fusion and adrenohepatic adhesion on the right side is reported. It is hypothesized that the basic lesion underlying this innocuous anomaly rests in the periadrenal mesenchyme. In the case of fusion of adrenal with kidney or liver the mesenchymal defect causes 1) retardation of capsule formation with parenchymal mixing and 2) failure of local differentiation into fetal and later adult fat cells. In the case of adhesion of adrenal to kidney or liver there is no retardation of capsule formation with parenchymal mixing but only failure to differentiate locally into fat cells. Consequently, there is no physical separation of these organs by interposition of fat cells and there is variable party-wall sharing of the capsule.