Usefulness of endoscopic ultrasonography in patients with "Idiopathic" acute pancreatitis

PURPOSE: No underlying cause is found in as many as 30% of patients with ac ute pancreatitis. The aim of this study was to evaluate the usefulness of e ndoscopic ultrasonography in the diagnosis of biliary tract pathology or ch ronic pancreatitis in these patients. SUBJECTS AND METHODS: We evaluated 168 patients who were referred with idio pathic pancreatitis. Diagnoses obtained by endoscopic ultrasonography were prospectively compared with those obtained at surgery in 101 patients, by e ndoscopic cholangiopancreatography in 49 patients, or by bile crystal analy sis and medical follow-up in 18 patients. RESULTS: Endoscopic ultrasonography was abnormal in 135 (80%) patients, 124 of whom had biliary tract disease. When the results of endoscopic ultrason ography were compared with those made after multidisciplinary investigation s, endoscopic ultrasonography correctly identified the cause-most commonly biliary tract disease-of the "idiopathic" pancreatitis in 155 (92%) of the 168 patients. CONCLUSIONS: Endoscopic ultrasonography is valuable in determining the caus e of acute pancreatitis in patients initially considered to have idiopathic pancreatitis. (C) 2000 by Excerpta Medica, Inc.