Replacement kidney lipomatosis after renal transplantation.

Renal sinus lipomatosis consists of abnormal fatty proliferation of the renal sinus, hilus, and perirenal spaces. Its pathogenesis is unknown, although it is generally associated with aging, renal atrophy, and long-standing chronic inflammation or urinary tract infection. Although this condition is rare, it may be important to recognize it in renal transplant recipients. We describe three cases of replacement kidney lipomatosis that occurred after cadaveric renal transplantation and discuss the possible differential diagnosis of this condition.