“…However, both these criteria may be shared by other acute abdominal emergencies such as perforated duodenal ulcer and intestinal obstruction, while patients with biliary calculi and acute cholecystitis often have increased serum amylase levels, which may reflect the functional and developmental inter-relationships of the biliary and exocrine pancreatic systems rather than the presence of acute pancreatitis. To overcome these difficulties, and to make the diagnosis of acute pancreatitis as objective as possible, several authors have urged that the diagnosis should be accepted only if the serum amylase on admission exceeds 1000 Somogyi U/dl (Trapnell, 1966), or 1200 IU/l (Imrie and Whyte, 1975), or is three to five times higher than the upper limit of the normal range (Wyatt, 1974;Bourke, 1975). Patients with lower values of serum amylase are thus automatically excluded from therapeutic trials.…”