Perinephric abscess associated with staghorn calculus on imaging

Perirenal suppration complicating a staghorn calculus. This severely infected kidney is not functional. Successful treatment consisted of en-bloc nephrectomy and excision of all perirenal infected fat. (A) Plain radiograph: A staghorn calculus is visualized in the pelvicaliceal system. (B) Computed tomography: The abscess (asterisk) progressed to the lumboabdominal wall with an inflammatory cutaneous reaction (arrowhead). The staghorn calculus is visible (arrow).