What is the mechanism underlying Kawasaki syndrome in the context of COVID-19?
The mechanisms underlying Kawasaki disease -a generalized vasculitis, in young children, of unknown, potentially post-viral etiology- are poorly understood. The rare COVID-19-associated inflammatory syndrome also features vasculitic changes, affects older children too and is often only associated with positive SARS-CoV-2 serology, but not viral shedding. Its mechanisms need to be elucidated and may include post-infectious, antibody and immune-complex mediated pathology. In adults, there are occasional cases of COVID-19-associated cutaneous vasculitis, possibly a localized manifestation of the disease that leads to severe generalized vasculitis in some children.89-91 Interestingly Kawasaki-like disease was not reported in Chinese cases and the first months of European cases. The season of the disease and environmental factors should be considered. The Chinese epidemic was mainly from January to March whereas the USA epidemic started in mid-March and is still ongoing.