Early Recognition of Emphysematous Pyelonephritis on Plain Radiography in the Emergency Department: A Case Report

Abstract

Emphysematous pyelonephritis is a rare but life-threatening necrotising renal infection characterised by gas formation within the renal parenchyma and surrounding tissues. It most commonly affects patients with diabetes mellitus and is associated with significant mortality, particularly in those who present with septic shock. We report a 44-year-old woman with type 2 diabetes mellitus and chronic paraplegia secondary to T10 spinal cord injury who presented to the emergency department with progressive constitutional symptoms and septic shock. Classical flank pain was initially absent. Laboratory investigations revealed marked leukocytosis and elevated lactate levels. Plain abdominal radiography demonstrated abnormal retroperitoneal gas densities over the left renal region that did not conform to normal bowel gas patterns, raising suspicion for emphysematous renal infection. Contrast-enhanced computed tomography subsequently confirmed extensive left emphysematous pyelonephritis with perinephric abscess formation. The patient was managed with aggressive resuscitation, broad-spectrum intravenous antimicrobial therapy and ultrasound-guided percutaneous drainage, resulting in clinical recovery. This case highlights the importance of maintaining a high index of suspicion in high-risk patients and recognising abnormal radiographic findings in the emergency department to facilitate early diagnosis and timely source control.