In early 2020, a new disease entity emerged in children as a result of infection with SARS-CoV-2. Multisystem inflammatory syndrome in children (MIS-C) was an acute inflammatory process that followed infection by 2 to 6 weeks and presented with fever and variously with rash, conjunctival injection, and red lips. Complaints of abdominal pain were common. Cardiac involvement with decreased myocardial contractility led to reduced ejection fraction and shock. Laboratory testing revealed markedly elevated inflammatory parameters. Initially the clinical presentation was confused with Kawasaki disease (KD), a coronary artery vasculitis of unknown etiology that shared several clinical features with MIS-C. It later became clear, however, that these were distinct diseases with different pathophysiology and different outcomes. The comparison of these 2 entities to understand the differences and similarities was the focus of this study.
