ABSTRACT
Xanthogranulomatous pyelonephritis, an uncommon chronic inflammatory renal disorder of middle-aged women, is rarely seen in childhood. A 10 year-old boy with focal type of this disease in upper and lower pole was experienced. Patient had a intermittent fever and right flank pain without palpable mass. The blood analysis only revealed ESR increase but no anemia, no leukocytosis. There was no history or signs of urinary tract infection or calculi. The urine analysis and culture showed nothing abnormal. An intravenous pyelogram, ultrasonogram, abdominal CT and selective renal arteriography only demonstrated a non functioning upper pole of right kidney. During operation, a gross finding and frozen section strongly showed xanthogranulomatous pyelonephritis and diagnosis was made on histological examination, After nephrectomy, there had been no evidence of disease recurrence during 2 years follow-up period.