Azathioprine is frequently used in the treatment of Crohn’s disease. A severe side effect is acute pancreatitis, which is specific for Crohn’s disease. Autoantibodies against exocrine pancreas occur in about 30% of Crohn’s disease cases but not in other inflammatory diseases. Pancreatic autoantibody positive Crohn’s disease patients might have a low grade inflammation of the pancreas which may be aggravated by the introduction of azathioprine, resulting in clinically overt acute pancreatitis. Rinse K Weersma et al. hypothesized that the presence of pancreatic autoantibodies in Crohn’s disease patients is associated with the development of azathioprine-induced pancreatitis.