Study could guide future treatment of multisystem inflammatory syndrome in children Children and adolescents with multisystem inflammatory syndrome in children (MIS-C) who are treated initially with intravenous immune globulin (IVIG) and glucocorticoids have reduced risk for serious short-term outcomes, including cardiovascular dysfunction, than those who receive an initial treatment of IVIG alone, a new study finds. MIS-C is a rare but serious--and sometimes fatal--condition associated with COVID-19, in which different body organs or systems become inflamed, including the heart, lungs, kidneys, brain, skin, eyes, or gastrointestinal system. It can occur weeks after having COVID-19 and even if the child or caregivers did not know the child had been infected.