Xanthogranulomatous pyelonephritis in an adolescent

: One case of xanthogranulomatous pyelonephritis diagnosed following nephrectomy is described, considering its outstanding characteristics such as male adolescent, right kidney, involvement with normal function and without pathological history for which there is no explanation to date. This disease usually occurs in women 60 years or older, suggesting a renal tumor. In 50% of the cases, urine cultures are positive for Escherichia coli or Proteus mirabilis; in accordance with different reports renal tissue cultures are positive in more than 90%. Malnutrition, calcification, urolithiasis and renal failure with hydronephrosis are common findings. The left kidney is more frequently involved. The etiology is unclear: many hypotheses are discussed, with malnutrition and peroxidase deficit as important causes.