Severe emphysematous pyelonephritis with extensive extra-renal gas dissemination: A radiological emergency

Emphysematous pyelonephritis (EPN) is a rare, life-threatening, necrotizing renal infection marked by gas forming within renal and peri-renal tissues. We report the case of a 36-year-old woman with no prior medical history, who presented acute severe flank pain and systemic sepsis. Laboratory workup revealed marked hyperglycemia and acute kidney injury, with glycated hemoglobin indicating previously undiagnosed diabetes mellitus. Imaging confirmed Class 3B EPN with extensive retroperitoneal gas. Percutaneous drainage failed, necessitating nephrectomy. The patient recovered and was discharged on postoperative day 14. This case underscores the importance of early CT imaging in rapidly identifying severe EPN, facilitating surgical intervention, and improving survival outcomes.