Outcome of nephrectomy and kidney-preserving procedures for the treatment of emphysematous pyelonephritis

Objective. Emphysematous pyelonephritis (EPN) is an acute necrotizing infection of the kidney characterized by gas formation. In order to compare the outcome of nephrectomy and kidney-preserving procedures for the treatment of EPN we reviewed our experiences of EPN over the past 18 years. Material and methods. The medical records of 17 patients with EPN treated between October 1986 and September 2004 were retrospectively reviewed. Abdominal X-ray and/or CT were used as diagnostic methods. Results. Women outnumbered men (12 vs five), and all patients had diabetes. Obstruction of the corresponding reno-ureteral unit was found in one patient. Thirteen of the 17 patients (76%) had poorly controlled diabetes (hemoglobin A1c > 7%). The diagnosis of EPN was confirmed by gas in the parenchymal or perinephric space as detected by abdominal X-ray or CT. Escherichia coli was the commonest organism present in urine cultures (52%), followed by Klebsiella pneumoniae (24%). Prompt efforts were made to control diabetes, and i.v. antibiotics were given. Nephrectomy was performed in 10 patients and nine patients survived (90% success rate). The success rate among those who received medical therapy only was 50% (2/4 patients). Percutaneous drainage was performed in three patients, two of whom survived (67% success rate). The overall mortality rate was 17.6% (3/17 patients). Conclusions. Immediate nephrectomy with glycemic control measures and antibiotic administration is crucial for the successful treatment of EPN. However, in inoperable cases, percutaneous drainage can be an effective treatment option.