Diffuse xanthogranulomatous pyelonephritis and staghorn calculus: report of one case.

Xanthogranulomatous pyelonephritis and staghorn calculus are rare in children. In this report, we describe a Chinese boy without history of urinary tract infection who developed insidious onset of left flank pain. Urine culture showed Proteus mirabilis infection. Sonography and computed tomography of the abdomen showed typical picture of xanthogranulomatous pyelonephritis and staghorn calculus. Photomicrography showed characteristic lipid-laden macrophage aggregates. After nephrectomy, he was symptom-free. In conclusion, xanthogranulomatous pyelonephritis should be considered in afebrile children with flank pain and staghorn calculus.