Immune thrombocytopenic purpura increased risk of subsequent pancreatitis: A Nationwide population cohort study.

Immune thrombocytopenic purpura (ITP) is characterized by thrombocytopenia and bleeding diathesis. Pancreatitis is a very rare complication but may be fatal. We analyzed data of newly diagnosed ITP patients, excluding those with a history of splenectomy, unknown sex or date of birth, or preexisting pancreatitis at the time of ITP diagnosis, and compared these with selected age-, gender-, and index-year-matched controls, using the Taiwan National Health Insurance Research Database from 1996 to 2013. The study enrolled 100,177 ITP patients and 100,177 controls. We found that pancreatitis risk was higher in secondary ITP patients, regardless of age group, gender, baseline Charlson comorbidity index (CCI) score, history of biliary stone, hyperlipidemia, or alcoholism, than in the control population. Primary ITP patients with CCI score 1 and without biliary tract stone history also showed a higher pancreatitis risk than the controls. The incidence rate and cumulative incidence of pancreatitis were increased in primary, secondary, and unspecified ITP cases. These phenomena may be related to the presence of autoantibodies against glycoprotein IIb/IIIa, or to IgG4, microparticle obstruction, or sclerosis. We noted a direct association between ITP and the development of pancreatitis in Taiwan population.