Pediatric focal xanthogranulomatous pyelonephritis: dynamic contrast-enhanced MRI findings.

Xanthogranulomatous pyelonephritis (XPN) is the result of chronic renal infection. It is very rare in childhood and the focal form, which is said to be more common in children, is often misdiagnosed as a renal tumor. We report a case of a focal XPN in a 14-year-old girl. The true preoperative diagnosis may be very hard in children especially in the focal form but it seems to be possible by the help of dynamic contrast-enhanced MRI.