Xanthogranulomatous pyelonephritis with multiple cutaneous fistulae.

Xanthogranulomatous pyelonephritis is characterized by a xanthogranulomatous inflammatory response by the kidney to bacterial infection. The actual histologic diagnosis of this condition is usually made by the pathologist following nephrectomy. Cutaneous fistulae and internal sinus formation, albeit rare, have been reported to occur. Herein we report a case of xanthogranulomatous pyelonephritis in which multiple internal and cutaneous sinuses first developed two months following nephrectomy.