DOI: https://doi.org/10.36347/sjmcr.2026.v14i08.008

Pages: 1789-1795

Emphysematous pyelonephritis (EPN) is a rare, life-threatening necrotizing infection of the renal parenchyma characterized by gas formation within the kidney and surrounding tissues. Its occurrence in an ectopic pelvic kidney is exceptionally rare and poses unique diagnostic and therapeutic challenges. We report the case of a 61-year-old non-diabetic male with an incidentally discovered left ectopic pelvic kidney who presented with EPN complicated by a massive psoas abscess. Initial management with endoscopic drainage and targeted antibiotic therapy achieved complete resolution of the infectious process. However, follow-up imaging revealed total renal replacement lipomatosis of the non-functional ectopic kidney harboring a staghorn calculus. Preoperative CT angiography delineated a dual arterial supply from the left common iliac artery and the distal abdominal aorta. An open subcapsular nephrectomy was performed, with histopathology confirming extensive tubular atrophy, massive adipose involution, dense fibrosis with lymphoplasmacytic infiltrates, and epithelioid granulomas with suppurative necrosis. The postoperative course was uneventful, with preserved renal function at three-month follow-up. This case illustrates the convergence of three rare urological entities, ectopic pelvic kidney, EPN in a non-diabetic patient, and renal replacement lipomatosis, and highlights the importance of multidisciplinary management, meticulous vascular mapping, and the subcapsular nephrectomy technique in the setting of intense perinephritic fibrosis.