[Localized form of xanthogranulomatous pyelonephritis in a child. Case report].

The authors report the case of a 4 1/2-year-old boy with a localized xanthogranulomatous pyelonephritis. Review of the literature shows that this rare condition is often misdiagnosed before surgery, a preoperative diagnosis of Wilms' tumor being proposed instead of the exact one which is of benign prognosis. The pathogenesis is unknown.