CD40LG and COVID-19: In our study, two patients with MIS-C had received vaccination against COVID-19, a 14-year-old male (vaccinated in November 2021, one dose) who developed disease five months later (he was IgG positive), and an 11-year-old male (vaccinated in February 2022) who developed the disease eight days later, but had positive IgG and IgM serology at diagnosis.