Kawasaki Disease and Multisystem Inflammatory Syndrome in Children: Common Inflammatory Pathways of Two Distinct Diseases.

Multisystem inflammatory syndrome in children (MIS-C) is a delayed postinflammatory disorder associated with the previous infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Initially, MIS-C was described as highly similar to Kawasaki disease (KD), a pediatric febrile systemic vasculitis that can lead to the development of coronary artery aneurysms (CAAs). While KD and MIS-C are both inflammatory disorders, the 2 entities differ in their epidemiological, clinical, immunological, and pathological features. MIS-C clinical and laboratory characteristics are more closely related to toxic shock syndrome (TSS) than KD, which informs the understanding of pathogenesis and potential therapeutic approaches.