Xanthogranulomatous pyelonephritis: a retrospective study of 10 cases and review of the literature.

We herewith report 10 patients with xanthogranulomatous pyelonephritis (XGP) who were treated in our department between the years 1988 and 2000. The patients' age ranged from 20 to 60 years (mean 45 years); there were seven males and three females giving a male-female ratio of 2.3:1. Sixty percent of the patients were over 50 years old. The lesion was unilateral in all cases and pyonephrosis was found in seven patients. Nine cases had associated renal stones (90%), which led to non-functioning kidney in all these cases. Two cases had associated fistulae (one uretero-colonic fistula and one reno-cutaneous fistula). One case of focal XGP was found to be associated with renal cell carcinoma while a second patient with diffuse obstructive type of XGP and renal stone had associated transitional cell carcinoma of the renal pelvis. In all patients, the urine culture was negative. Pus culture revealed Escherechia coli in four cases (40%), Salmonella Para B in one, and no organism could be grown in four other cases. One case did not have any pus. All patients were treated with nephrectomy.