Xanthogranulomatous pyelonephritis in childhood: case report and review of English and Japanese literature.

Xanthogranulomatous pyelonephritis is an uncommon disease that is usually seen in middle-aged women and is much rarer in children. We report a case of diffuse xanthogranulomatous pyelonephritis in a 3-year-old boy who had a nonfunctioning hydronephrotic right kidney on an excretory urogram. A review of the English and Japanese literature on xanthogranulomatous pyelonephritis in childhood revealed 2 remarkable differences regarding the incidence of sex and radiological findings. The majority of patients were girls in the English literature, whereas the opposite sex was seen in the majority of cases in Japan. The involved kidney was functioning on an excretory urogram in the majority of cases reported in the English literature, however, in all cases from Japan the involved kidney was non functioning. These findings further support the newer concept that xanthogranulomatous pyelonephritis in childhood exists in focal as well as diffuse forms.