Predictors of poor kidney function in patients with emphysematous pyelonephritis: a retrospective observational study

Background: Emphysematous pyelonephritis (EPN) is a well-known clinical condition characterized by an aggressive, gas-forming infection of the kidney caused by uropathogenic bacteria. There is growing interest in identifying the effects of EPN on long-term renal function and the factors that can help predict its impact. Objectives: This study evaluated risk factors for the development of poorly functioning kidneys (PFK) in patients diagnosed with EPN. Design: A retrospective study was conducted at a university teaching hospital on patients with EPN from January 2019 to December 2024. Methods: -value 50% parenchymal involvement on initial imaging was an independent and significant predictor of PFK. Conclusion: EPN is a fulminant renal infection with a high risk of renal functional deterioration. Renal parenchymal involvement of >50% on initial imaging emerged as the most significant and independent predictor of poor renal function. Additional contributory factors included RBS >200 mg/dL, Huang-Tseng Class 3b, and persistence of gas in the renal parenchyma on follow-up. Recognizing these clinical and radiological predictors can support early risk stratification, guide patient counseling, and inform individualized management strategies aimed at preserving renal function.