Xanthogranulomatous pyelonephritis. A report of 2 cases.

Xanthogranulomatous pyelonephritis (XGP) is a rare form of chronic pyelonephritis. The present author has found about 150 cases on going through the literature. The lipid filled "foam cell" is typical of the condition. The preoperative diagnosis is often renal carcinoma. The treatment is nephrectomy. It is important to make the diagnosis in order to avoid unnecessary radical surgery. A unilateral non-functioning kidney with urinary tract infection (with or without calculi) should lead to the condition being suspected. The prognosis is good. Two new cases that both illustrate the condition well are presented.