Xanthogranulomatous pyelonephritis with pancreatic infiltration: A rare case report.

Xanthogranulomatous pyelonephritis (XGP) is a rare chronic infection of the kidney, occasionally extending to adjacent organs. We report a 45-year-old woman with recurrent renal colic and left flank pain. Imaging showed a "bear paw" kidney with staghorn calculi and infiltration of the pancreatic tail. After antibiotic therapy, en bloc nephrectomy with splenopancreatectomy was performed. Histology confirmed XGP extending into the pancreas. Recovery was uneventful. Pancreatic involvement in XGP is extremely rare and may mimic malignancy; recognizing characteristic imaging features is crucial for accurate diagnosis and surgical planning.