Xanthogranulomatous pyelonephritis with psoas abscess and renocolic fistula.

Xanthogranulomatous pyelonephritis (XGP) is an uncommon inflammatory disease of the kidney 1. Diffuse XGP is a rare condition which may spread into the pelvic cavity leading to fatal complications from a psoas muscle abscess and/or renocolic fistula 2. In diffuse type, nephrectomy and excision of the fistula is the recommended treatment.