Urographic and angiographic changes in acute unilateral pyelonephritis.

The pyelographic and angiographic changes in acute unilateral bacterial pyelonephritis are illustrated in our series of 12 patients. The radiographic abnormalities were completely reversible within a few weeks after clinical recovery. Complications (abscess) occurred in only one patient. Unilateral renal enlargement, diffuse or focal, impaired or absent excretory function, and attenuated calyces were the predominant findings; non-obstructive pelvicalyceal and/or ureteral dilatation were infrequent. Angiographic studies (fivepatients), performed to rule out vascular occlusion, tumour or carbuncle, showed attenuated and somewhat stretched intrarenal vessels associated with the diffuse or focal cortical swelling. Occasionally, a characteristic striated nephrogram is seen.