Hyperamylasemia in inflammatory bowel disease.

We determined the prevalance and significance of hyperamylasemia in 180 patients with idiopathic inflammatory bowel disease (IBD) (83 with ulcerative colitis, and 97 with Crohn's disease). Serum total amylase and pancreatic and salivary isoamylase activity were measured in all patients. In all patients with hyperamylasemia, we measured isoamylase activity by cellulose acetate electrophoresis and lipase activity, assayed for the presence of macroamylase, and carried out pancreatic ultrasound examination and barium studies of the upper gastrointestinal tract. Eight of 97 patients with Crohn's disease (8%) had hyperamylasemia; 4 of them had an elevated pancreatic isoamylase and 2 a raised lipase activity. All patients with hyperamylasemia had normal ultrasonographic scans of the pancreas and no evidence of duodenal involvement on barium meal. None had macroamylasemia. We found no relationship of hyperamylasemia to disease site, activity, and duration or therapy and no patient developed clinical evidence of pancreatitis. We conclude that a small but important number of patients with Crohn's disease have hyperamylasemia not associated with overt pancreatitis. In the absence of appropriate indications, it requires no investigation.