Computerized tomography in xanthogranulomatous pyelonephritis.

Computerized tomography offers the means to recognize changes in the kidney associated with xanthogranulomatous pyelonephritis. The preoperative extent of the inflammatory process, reaction of adjacent parenchymal structures, and extension to the muscles and abdominal wall are identifiable on computerized tomography. The presence of obstructing renal stones, thickening of the perirenal fascia and inability of the kidney to handle intravenously injected contrast medium can be assessed with computerized tomography. Low density renal areas measured on computerized tomography may indicate lipid infiltration of the kidney or incorporation of the fat of the renal bed into the tumefactive mass.