Xanthogranulomatous pyelonephritis

Case contributed by Richard Dittrich
Diagnosis probable


Patient presented with symptoms of colitis and a history of recurrent urinary tract infections cultured as Escherichia coli (then later as Pseudomonas aeruginosa)

Patient Data

Age: 50 years
Gender: Female

There is a staghorn calculus of the left renal pelvis and further extensive calculi within the dilated calyces, with thinning of the renal parenchyma in keeping with xanthogranulomatous pyelonephritis. Left perinephric and para-aortic lymphadenopathy. There is thickening of the proximal left ureter with periureteric fat stranding, likely to represent pyelitis/urethritis. The right kidney is within normal limits with a simple cortical cyst.

Sigmoid colitis/proctitis.

Bilateral pleural effusions and bibasal collapse/consolidation.

Abdominal X-ray


Renal calculi and also ulcerative colitis flare.

Case Discussion

Xanthogranulomatous pyelonephritis is a form of pyelonephritis and is a chronic inflammatory condition that is caused by infection of the kidney, usually as a secondary complication to staghorn calculi.  The differential must include renal carcinomas, malakoplakia, megalocytic interstitial nephritis and perhaps leiomyosarcoma.

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