Diagnostic yield and reliability of endoscopic ultrasonography in patients with idiopathic acute pancreatitis

Abstract

Objectives. To evaluate the diagnostic yield of endoscopic ultrasonography (EUS) in patients with idiopathic acute pancreatitis (IAP), find factors predictive of a positive EUS finding in these patients and investigate whether these etiological findings are maintained during follow-up. Material and methods. We performed EUS in patients with IAP between July 2004 and August 2007. We recorded epidemiological data, the number and severity of previous bouts of pancreatitis and gallbladder status. Results. A total of 44 patients were included in the study. EUS was normal in seven patients (16%). In the remaining 37 patients (84%) we found cholelithiasis (n = 3), microlithiasis (n = 20), chronic pancreatitis (n = 14), pancreas divisum (n = 3), pancreatic mass (n = 1), apudoma (n = 1), cystic tumor of the pancreas (n = 2) and choledocholithiasis (n = 2). Positive EUS findings were not influenced by sex, severity of pancreatitis or recurrent disease. Patients aged < 65 years (age > or < 65 years: 73.9% versus 95.2%; P = 0.097) and patients with gallbladder in situ (cholecystectomy versus non-cholecystectomy: 63.6% versus 90.9%; P = 0.054) showed a tendency to have positive EUS findings. Mean follow-up was 28.95 ± 10.86 months (range 12–64 months; median 28 months). During follow-up the etiological diagnosis was changed in two patients, lowering the diagnostic yield to 79%. Conclusions. EUS identified the cause of IAP in 79% of patients. Patients with gallbladder in situ and patients aged < 65 years showed a tendency to have positive EUS findings. The majority of the diagnoses provided by EUS are maintained during follow-up and seem to be reliable.