[Prognostic factors in emphysematous pyelonephritis]

The purpose of this study is to analyze our experience with 18 cases of Emphysematous pyelonephritis (EPN) in a tertiary care center and describe our treatment strategy.

Of 262 patients admitted with acute pyelonephritis, 18 had CT findings of EPN. The Wan and Huang classifications were used. We assessed the clinical, radiological, and therapeutic characteristics of these patients and investigated potential prognostic factors of mortality.

Between 2005 and 2010, 17 women and 1 man with EPN were treated. Mean age was 52.4 years. Diabetes was found in 66% and hypertension in 72%. The most common clinical findings were tachycardia (11), fever (11) and flank pain (9); 66% (12) presented with severe sepsis and 2 had septic shock. Acute renal injury developed in 61%. Nine patients were treated exclusively with conservative management; 5 had double J stenting, 3 had CT-guided PCD and 1 required nephrectomy after unsuccessful medical management. Mortality was 11%. Altered consciousness (P=.0001), multiple organ failure (P=.0004), hyperglycemia (P=.003) and elevated leukocyte count (> 20000 K) (P=.01) were more frequent among patients dying from EPN. No difference in mortality was found between patients managed conservatively and those undergoing invasive therapy.

Although rare, EPN should be suspected in patients with multiple comorbidities presenting with severe sepsis. Altered consciousness, multiple organ failure, hyperglycemia and elevated leukocyte count are poor prognosis indicators. Invasive management should be used judiciously and medical treatment can be a safe strategy in selected cases.