VASCULITIS SYNDROMES: Edited by Hasan Yazici and Yusuf YaziciA cursed goodbye kiss from severe acute respiratory syndrome-coronavirus-2 to its pediatric hosts: multisystem inflammatory syndrome in childrenHaslak, Fatih; Gunalp, Aybuke; Kasapcopur, Ozgur Author Information Department of Pediatric Rheumatology, Istanbul University-Cerrahpasa, Cerrahpasa Medical School, Istanbul, Turkey Correspondence to Ozgur Kasapcopur, Department of Pediatric Rheumatology, Istanbul University-Cerrahpasa, Cerrahpasa Medical School, Istanbul, Turkey. Tel: +90 5322129111; e-mail: [email protected]; [email protected] Current Opinion in Rheumatology 35(1):p 6-16, January 2023. | DOI: 10.1097/BOR.0000000000000910 Buy Metrics Abstract Purpose of review We aimed to summarize a novel disease called multisystem inflammatory syndrome in children (MIS-C), which develops several weeks after a severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) illness. Recent findings Given the rarity of the disease, the question of why a minority of children develop MIS-C is not known. Certain intrinsic susceptibility factors in the host have been described. In addition to hyperinflammation induced by the innate and acquired immune cells, evidence of molecular mimicry was presented for the disease pathogenesis. As there is an increasing number of infected individuals and mass vaccination schedules, concerns regarding the usefulness of the existing diagnostic criteria sets raised. Summary Although children are likely to have a milder COVID-19 course compared with adults, MIS-C as a postinfectious and life-threatening complication was reported in the pediatric age. After 2 years of the disease definition, optimal treatment regimes, effective preventive measures, and long-term outcomes are still debated. Copyright © 2022 Wolters Kluwer Health, Inc. All rights reserved.