ABSTRACT
Background: A novel multisystem inflammatory syndrome in children (MIS-C) temporally associated with the coronavirus disease 2019 (COVID-19) infection has been reported, arising weeks after the peak incidence of COVID-19 infection in adults. Patients with MIS-C have been reported to have cardiac involvement and clinical features overlapping with other acute inflammatory syndromes such as Kawasaki disease, toxic shock syndrome, and macrophage activation syndrome. Multisystem inflammatory syndrome in children may follow COVID-19 infection, most of the time after its asymptomatic form, even though it can lead to serious and life-threatening illness. Case summary: In this case series, we discuss two cases of young adults with no former medical history who fit with the criteria defined in MIS-C. They both developed a refractory cardiogenic shock and required intensive care treatment including mechanical circulatory support, specifically the use of venous-arterial extracorporeal membrane oxygenation. They were both treated early with intravenous immune globulin and adjunctive high-dose steroids. They recovered ad integrum in less than 2 weeks. Discussion: Multisystem inflammatory syndrome in children occurs 2-4 weeks after infection with severe acute respiratory syndrome coronavirus 2. Patients with MIS-C should ideally be managed in an intensive care environment since rapid clinical deterioration may occur. It would be preferable to have a multidisciplinary care to improve outcomes. Patients should be monitored for shock. Elucidating the mechanism of this new entity may have importance for understanding COVID-19 far beyond the patients who have had MIS-C to date. The pathogenesis seems to involve post-infectious immune dysregulation so early administration intravenous immune globulin associated with corticosteroids appears appropriate. It implies early recognition of the syndrome even in young adults.