Epidemiologic and clinical characteristics of multisystem inflammatory syndrome in adults: a rapid review

Abstract
Multisystem inflammatory disease in children (MIS-C) is one of the severe presentations of
the coronavirus disease 2019 (COVID-19) that has been described in the literature since the
beginning of the pandemic. Although MIS-C refers to children, cases with similar clinical
characteristics have been recently described in adults. A description of the epidemiologic and
clinical characteristics of multisystem inflammatory disease in adults (MIS-A) is a starting point
for better knowledge and understanding of this emerging disease.

We identified nine case reports of MIS-A in the literature, five from the United States, two from
France and two from the United Kingdom. The case descriptions revealed similarities in clinical
features, including occurrence during post-acute disease phase, fever, digestive symptoms,
cardiac involvement and elevated inflammatory markers. All the patients were hospitalized,
three required admission to the intensive care unit and one died. The most common treatments
were intravenous immunoglobulin, prednisolone and aspirin.
These findings suggest that MIS-A is a severe complication of COVID-19 disease that can lead
to death. Further studies to improve our understanding of the pathogenesis of MIS-A, which
will help improve treatment decisions and prevent sequelae or death.