DOI: https://doi.org/10.36347/sjmcr.2026.v14i06.015

Pages: 1388-1391

Xanthogranulomatous pyelonephritis (XGP) is a rare, chronic destructive granulomatous infection of the renal parenchyma, typically associated with long-term urinary tract obstruction. While local extra-renal extension is common, transdiaphragmatic spread leading to a nephro-pleural fistula is an extremely rare and life-threatening complication. We report the case of a 48-year-old male with a history of pulmonary tuberculosis who presented with acute respiratory distress and a 'white-out' of the left hemithorax. Contrast-enhanced CT revealed the pathognomonic 'bear paw sign' in the left kidney, a staghorn calculus, and a direct fistulous communication through the diaphragm into the pleural space. Management required a staged approach: urgent percutaneous drainage of the renal and pleural collections followed by a delayed total nephrectomy. This case underscores the role of the radiologist in identifying the subtle signs of fistulous tracking in the setting of chronic renal sepsis.