A Prospective Study of Role of Minimally Invasive Approaches for Renal Salvageability in Management of Emphysematous Pyelonephritis

Abstract

Introduction: Emphysematous pyelonephritis (EPN) is a severe, potentially life-threatening necrotizing renal infection characterized by gas formation within the renal parenchyma and surrounding tissues. Although nephrectomy was traditionally considered the definitive treatment, minimally invasive approaches have increasingly been used to achieve renal preservation.

Aim & Objective: This study evaluated renal salvageability with minimally invasive management and identified factors associated with treatment failure and the need for invasive intervention.

Material & Methods: The 40 patients with EPN were evaluated clinically, biochemically, microbiologically, and radiologically using CT-based Huang classification. Initial management included antibiotics, DJ stenting and/or percutaneous catheter drainage (PCD). Patients requiring open drainage or nephrectomy following failure of minimally invasive treatment were considered to have poor outcomes. Statistical analysis was performed using unpaired t-test and Fisher’s exact test, with p<0.05 considered significant.

Results: The mean age was 56.2±7.76 years, with females comprising 74% of patients. Diabetes was present in 87.5%. Minimally invasive management achieved renal salvage in 90% (36/40) of patients, while 10% required invasive intervention. Elevated serum creatinine (3.63 vs. 1.48 mg/dL, p=0.0019), blood urea (99.5 vs. 41.42 mg/dL, p=0.0004), thrombocytopenia (p=0.0001), leukocytosis (p=0.011), shock (p=0.0027), altered mental status (p=0.004), positive blood cultures (p=0.0001), urinary obstruction (p=0.017), and advanced CT severity (p=0.00001) were significantly associated with poor outcomes. E. coli was the predominant urinary pathogen (72.5%).

Conclusion: Minimally invasive treatment provides a high rate of renal salvage in EPN and should be considered as the initial management strategy. Early identification of renal dysfunction, thrombocytopenia, shock, altered sensorium, bacteremia, obstruction, and advanced CT disease can help predict treatment failure and guide timely escalation to invasive procedures.

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