Imaging Spectrum of Renal Replacement Lipomatosis: A Case Series

Abstract

Renal replacement lipomatosis is a rare benign entity, characterized by diffuse replacement of renal parenchyma, sinus and hilum with adipose tissue resulting in renal parenchymal atrophy. Etiology may be secondary to obesity, cushing's syndrome, corticosteroid excess or idiopathic. Renal replacement lipomatosis is usually secondary to renal calculus and renal tuberculosis, occasionally occurs after renal infarction and is frequently associated with xanthogranulomatous pyelonephritis. CT provides a definitive diagnosis of renal replacement lipomatosis and is considered superior to ultrasonography, which is not very sensitive for detecting fatty proliferation. CT is considered to be best to differentiate renal replacement lipomatosis from other fat rich lesions, such as renal angiomyolipoma, retroperitoneal lipoma and liposarcoma.