Emphysematous pyelonephritis: diagnosis and treatment.

Emphysematous pyelonephritis is a rare life-threatening bacterial infection usually occurring in patients with diabetes mellitus and producing gas within the renal parenchyma and/or perirenal tissue. We add four cases to the 62 previously reported in the literature. The overall mortality is 38%, with only 29% survival for those treated medically compared to 71% for those given both medical and surgical treatment. Early diagnosis with the aid of renal ultrasonography and/or computerized axial tomography and aggressive early combined medical-surgical management are emphasized.