The urgent diagnosis of gallstones in acute pancreatitis: a prospective study of three methods.

Ultrasonography (US), radionuclide biliary scanning (RBS), and biochemical tests were performed within 72 h of admission in 83 patients with acute pancreatitis in an attempt to define those with gallstones as an aetiological factor. US was 92 per cent accurate in the 80 per cent of patients in whom the gallbladder was demonstrated. There were no false positives. Sixty-seven per cent of patients with gallstones were diagnosed although this improved to 78 per cent when US was repeated following the patients' clinical improvement. The pattern of RBS was completely normal in 46.5 per cent of patients with biliary pancreatitis and 64 per cent of patients with non-biliary pancreatitis. Biochemical tests completely separated 47 per cent of patients with gallstones from those without. Used in combination with US these two methods accurately identified 81 per cent of patients in the biliary group. In conclusion US was found to be a rapid and accurate method of gallstone detection but used alone it has limited usefulness. RBS can be time consuming and was found to be of doubtful value. Biochemical tests were helpful in indicating a proportion of patients who had gallstones which were not detected by US, and therefore have a practical application. Current methods of gallstone detection in patients with acute pancreatitis are far from ideal and further studies are indicated.