Plasma N-terminal pro-B-type natriuretic peptide (BNP) in mesalazine-induced myopericarditis.

Mesalazine (5-aminosalicylic acid)-based products are a widely used treatment for inflammatory bowel disease in children and adults. Associated myopericarditis is an uncommon but recorded phenomenon related to drug hypersensitivity. Unless recognised, this important complication may culminate in the development of dilated cardiomyopathy and severe heart failure. We report the case of a boy with Crohn's disease who developed myopericarditis 14 days after starting treatment with mesalazine. Discontinuation of the drug rapidly led to normalisation of left ventricular structure and function, and a parallel improvement in the levels of plasma N-terminal pro-B-type natriuretic peptide and other markers of myocardial damage. Clinicians should be aware of this potentially life-threatening adverse effect of mesalazine therapy, which is quickly and fully reversible on cessation of the agent. © BMJ Publishing Group Limited 2019. No commercial re-use. See rights and permissions. Published by BMJ.