Emphysematous pyelonephritis is a rare and life-endangering suppurative inf
ection characterized by the production of gas in the renal parenchyma and p
erirenal space. It affects mainly patients with diabetes mellitus. Authors
report three cases of emphysematous pyelonephritis and insist on the role o
f radiological investigations in diagnosis. Through an exceptional case of
emphysematous pyelonephritis revealed by hematemesis, they remind the progr
ession route of infection from retroperitoneal to mediastinal space. Progno
sis of emphysematous pyelonephritis depends on the patient's general health
status and rapidity of diagnosis and treatment. Percutaneous drainage is a
n alternative to major surgery and is particularly indicated in cases of si
ngle kidney or in an inoperable patient. (C) 2001 Editions scientifiques et
medicales Elsevier SAS.