Imaging of acute pyelonephritis

: Despite the advances achieved in imaging methods, the diagnosis of acute pyelonephritis rests on clinical and bacteriological date. Yet imaging is of considerable value to exclude a possible obstacle in the excretory canals which might be responsible for acute pyelonephritis. Ultrasonography associated with plain abdominal radiography without preparation or with intravenous urography is the choice method. In case of atypical forms, patients at risks or resistance to medical treatment, computerized tomography provides an information that is invaluable for the diagnosis as well as for the prognosis.