A Case of Adult-Onset Kawasaki Disease in an Adolescent Occurring during the COVID-19 Pandemic

We report the occurrence of the adult-onset type of Kawasaki disease (KD) with classic mucocutaneous manifestations of KD, cholestatic liver disease, multiple splenic infarcts, and residual multiple coronary artery dilatations in a previously healthy 14-year-old male adolescent 16 days after having received one dose of the BNT162b2 coronavirus disease 2019 (COVID-19) mRNA vaccine. First, the report serves to highlight the diagnostic challenges of adult-onset KD often resulting in therapeutic delay and the frequently reported occurrence of persistent cardiovascular sequelae. Second, the report emphasizes that the temporal association of KD with the administration of a COVID-19 vaccine will likely be a frequent constellation in the near future, raising questions of a causative association. While there is currently no evidence of such an association in persons above 5 years of age, large-scale vaccination of children below 5 years of age will require close surveillance of vaccine-related adverse events.