Multisystem Inflammatory Syndrome in Adults Associated With COVID-19: A Case Series on the Importance of Early Diagnosis and Corticosteroid Therapy in Prognosis

Multisystem inflammatory syndrome in adults (MIS-A) is a rare condition that can occur after an adult has been infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). It can occur anywhere between two and 12 weeks after the beginning of acute coronavirus disease 2019 (COVID-19) infection and is characterized by extrapulmonary multiorgan failure. It is primarily seen in young and previously healthy individuals. The exact prevalence of MIS-A is unclear. It is likely underdiagnosed due to overlapping symptoms with severe COVID-19 and difficulty in identifying the syndrome without a preceding COVID-19 infection. The pathogenesis of MIS-A is also largely unknown but is likely caused by an immune response that is dysregulated or antibody-mediated. Treatment primarily involves corticosteroids, but severe cases may require intravenous immune globulin (IVIG). The timing of starting corticosteroid therapy is crucial, as delays can result in increased complications and a longer hospital stay.