Azathioprine-induced Acute Pancreatitis in Patients with Inflammatory Bowel Diseases--A Prospective Study on Incidence and Severity

J Crohns Colitis. 2016 Jan;10(1):61-8. doi: 10.1093/ecco-jcc/jjv188. Epub 2015 Oct 13.


Background and aims: Azathioprine [AZA] is recommended for maintenance of steroid-free remission in inflammatory bowel disease IBD. The aim of this study has been to establish the incidence and severity of AZA-induced pancreatitis, an idiosyncratic and major side effect, and to identify specific risk factors.

Methods: We studied 510 IBD patients [338 Crohn's disease, 157 ulcerative colitis, 15 indeterminate colitis] with initiation of AZA treatment in a prospective multicentre registry study. Acute pancreatitis was diagnosed in accordance with international guidelines.

Results: AZA was continued by 324 [63.5%] and stopped by 186 [36.5%] patients. The most common cause of discontinuation was nausea [12.2%]. AZA-induced pancreatitis occurred in 37 patients [7.3%]. Of these: 43% were hospitalised with a median inpatient time period of 5 days; 10% had peripancreatic fluid collections; 24% had vomiting; and 14% had fever. No patient had to undergo nonsurgical or surgical interventions. Smoking was the strongest risk factor for AZA-induced acute pancreatitis [p < 0.0002] in univariate and multivariate analyses.

Conclusions: AZA-induced acute pancreatitis is a common adverse event in IBD patients, but in this study had a mild course in all patients. Smoking is the most important risk factor.

Keywords: Azathioprine; Crohn’s disease; inflammatory bowel disease; lipase; pancreatitis; smoking; ulcerative colitis.

Publication types

  • Multicenter Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acute Disease
  • Adult
  • Age Distribution
  • Aged
  • Analysis of Variance
  • Azathioprine / administration & dosage
  • Azathioprine / adverse effects*
  • Colitis, Ulcerative / drug therapy*
  • Colitis, Ulcerative / pathology
  • Crohn Disease / drug therapy*
  • Crohn Disease / pathology
  • Female
  • Germany
  • Humans
  • Incidence
  • Inflammatory Bowel Diseases / drug therapy
  • Inflammatory Bowel Diseases / pathology
  • Logistic Models
  • Male
  • Middle Aged
  • Multivariate Analysis
  • Pancreatic Function Tests
  • Pancreatitis / chemically induced*
  • Pancreatitis / epidemiology*
  • Pancreatitis / physiopathology
  • Prognosis
  • Prospective Studies
  • Registries
  • Risk Assessment
  • Severity of Illness Index
  • Sex Distribution


  • Azathioprine