Kawasaki Disease

Kawasaki disease (KD) is an acute pediatric vasculitis mostly occurring in children under the age of five. Although its exact pathogenesis remains unknown, KD is hypothesized to be caused by infectious triggers, such as the novel SARS-CoV-2 virus, that elicit a hyperinflammatory response in genetically predisposed children. KD can lead to coronary artery aneurysms (CAA), making it the most common cause of acquired heart disease in children. Although treatment with intravenous immunoglobulin (IVIG) and aspirin has diminished the incidence of CAA from 20% to 25% to about half, IVIG resistance occurs in up to 20% to 40% of cases and is associated with increased risk of developing CAA. A great concern is treatment delay due to late diagnosis, especially in case of incomplete presentation at a young age, increasing the risk of developing CAA. A small proportion of children with KD present with Kawasaki disease shock syndrome (KDSS), which can present with complications including cardiac dysfunction, hypotension, and laboratory findings of severe inflammation, similar to the current postinfectious, coronavirus-induced Multi-Inflammatory Syndrome in Children (MIS-C). It is increasingly recognized that coronary artery function abnormalities persist even if CAA resolve. Therefore, adequate follow-up with echocardiography as well as additional angiography (i.e., cardiac magnetic resonance imaging [cMRI], coronary computed tomographic angiography [cCTA]), coronary angiography [CAG] should be considered when CAA are detected. Future studies are paramount in untangling the mechanisms behind KD to optimize patient-tailored treatment and monitoring of cardiac sequelae in KD.