Objectives: To identify the prognostic factors, assess the outcome of conservative management, and modify the existing radiologic classification of emphysematous pyelonephritis.
Methods: Forty-one consecutive patients diagnosed with emphysematous pyelonephritis between January 2001 and February 2007 were studied retrospectively. On the basis of computerized tomographic scan they were grouped into four classes (1 to 4). The management was conservative with antibiotics alone or with a combination of percutaneous drainage and antibiotics.
Results: Thirty-eight (93%) of a total of 41 patients were diabetic. Escherichia coli (in 97%) was the predominant pathogen identified in pus culture. With antibiotics alone treatment was successful in 40%, and with a combination of percutaneous drainage and antibiotics the success rate was 80%. None underwent nephrectomy as a primary procedure. The risk factors for mortality were thrombocytopenia, shock, altered sensorium, and hemodialysis. In the absence of risk factors the success rate with conservative management was 100%. The mortality rate was 27%, 75%, and 100% in the presence of one, two, and three risk factors, respectively. The mortality rate in class 1, 2, 3, and 4 was 9%, 13%, 50%, and 33% respectively. The overall success rate was 78%.
Conclusions: A combination of percutaneous drainage with antibiotics offers an effective therapy for emphysematous pyelonephritis.