Mesalazine-Induced Myocarditis in a 17-Year-Old: A Case Report

Myocarditis is defined as inflammation of the myocardial tissue and is most frequently associated with infectious aetiologies, autoimmune or inflammatory disorders, ischaemic injury, and exposure to cardiotoxic agents. There is a higher incidence among younger males. The clinical spectrum is broad, ranging from non-specific manifestations such as fatigue and chest discomfort to fulminant presentations involving acute heart failure and cardiogenic shock. Mesalazine (also known as 5-aminosalicylic acid (5-ASA)) is an anti-inflammatory drug used in the treatment of inflammatory bowel diseases (IBD), specifically for mild to moderate ulcerative colitis as well as Crohn's disease. This report describes the case of a 17-year-old male patient with Crohn's disease who presented to the Accident & Emergency department with palpitations and chest pain two weeks following the initiation of mesalazine. Clinical examination, biochemical cardiac markers, such as troponin and N-terminal pro-B-type natriuretic peptide (NT-pro BNP), as well as cardiac imaging, all confirmed myocarditis with high suspicion that it was precipitated by the induction of mesalazine. This case report demonstrates a rare complication of mesalazine. Early recognition and prompt removal of triggers in this case was necessary in mitigating the risk of a possible adverse event related to untreated myocarditis, thus emphasising the critical role of timely diagnosis and intervention.