Co-existent massive renal replacement lipomatosis and xanthogranulomatous pyelonephritis--a case report.

Renal replacement lipomatosis is a benign condition that may assume major clinical significance by producing pyelocalyceal deformities that may be mistaken for true renal masses. While the number of reported cases of renal replacement lipomatosis has been relatively small, this entity's prevalence is probably underestimated. We report a case of co-existent massive renal replacement lipomatosis and xanthogranulomatous pyelonephritis.