SARS-CoV-2-related MIS-C: A key to the viral and genetic causes of Kawasaki disease?
Multisystem inflammatory syndrome in children (MIS-C) emerged in April 2020 in communities with high COVID-19 rates. This new condition is heterogenous but resembles Kawasaki disease (KD), a well-known but poorly understood and clinically heterogenous pediatric inflammatory condition for which weak associations have been found with a myriad of viral illnesses. Epidemiological data clearly indicate that SARS-CoV-2 is the trigger for MIS-C, which typically occurs about 1 mo after infection. These findings support the hypothesis of viral triggers for the various forms of classic KD. We further suggest that rare inborn errors of immunity (IEIs) altering the immune response to SARS-CoV-2 may underlie the pathogenesis of MIS-C in some children. The discovery of monogenic IEIs underlying MIS-C would shed light on its pathogenesis, paving the way for a new genetic approach to classic KD, revisited as a heterogeneous collection of IEIs to viruses. © 2021 Sancho-Shimizu et al. ; CGIEU0000219140; ANR-10-LABX-62-IBEID, ANR-20-CO11-0001; 70931; UL1 TR001866; MR/ S032304/1; National Institutes of Health: K08AI135091, R01AI088364, R01AI148963, R01AI150300, R01AI151029, R21AI144315-02S1; Howard Hughes Medical Institute; National Human Genome Research Institute: U24HG008956, UM1HG006504; National Institute of Allergy and Infectious Diseases; Burroughs Wellcome Fund; Glenn Foundation for Medical Research: EQU201903007798; St. Giles Foundation; American Academy of Allergy Asthma and Immunology; National Center for Advancing Translational Sciences; Rockefeller University; Fondation du Souffle; Michael Smith Foundation for Health Research; National Health and Medical Research Council; Agence Nationale de la Recherche: ANR-10-IAHU-01; University of New South Wales; Fonds Wetenschappelijk Onderzoek; Instituto de Salud Carlos III: COV20_01333, COV20_01334; Ministerio de Ciencia e Innovación: RTC-2017-6471-1; Horizon 2020: 824110 ; Our studes are also funded by Instituto de Salud Carlos III (COV20_01333 and COV20_01334), the Spanish Ministry of Science and Innovation (RTC-2017-6471-1; AEI/FEDER, UE), and Cabildo Insular de Tenerife (CGIEU0000219140 and ?Apuestas cient?ficas del ITER para colaborar en la lucha contra la COVID-19?). Work at the Neurometabolic Diseases laboratory is supported by the European Union's Horizon 2020 research and innovation programme under grant agreement No 824110. H. C. Su and L. D. Notarangelo as part of COVID-HGE are supported by the Intramural Research Program of the NIAID, National Institutes of Health. IM is a senior clinical researcher at the FWO Vlaanderen, SD is a FWO predoctoral mandate recipient. ; Our studies are funded by the Howard Hughes Medical Institute, the Rockefeller University, the St. Giles Foundation, the National Institutes of Health (R01AI088364 to J.-L. Casanova and S.-Y. Zhang; R01AI148963, R01AI151029, and R01AI150300 to D. Bogunovic; K08AI135091 to S.E. Henrickson; R21AI144315-02S1 to C.L. Lucas), the National Center for Advancing Translational Sciences, National Institutes of Health Clinical and Translational Science Award program (UL1 TR001866), the Yale Center for Mendelian Genomics and the GSP Coordinating Center funded by the National Human Genome Research Institute (UM1HG006504 and U24HG008956), Institut National de la Santé et de la Recherche Médicale and Université de Paris, the French National Research Agency (ANR) Résilience-Covid-19 grant GenMIS-C, the ANR "Investments for the Future" program (ANR-10-IAHU-01), the Integrative Biology of Emerging Infectious Diseases Laboratory of Excellence (ANR-10-LABX-62-IBEID), the ANR project AABIFNCOV (ANR-20-CO11-0001), the French Foundation for Medical Research (EQU201903007798), the French Foundation for Medical Research and ANR GENCO-VID project, the ANRSCOV05 project, the Square Foundation, Grandir - Fonds de solidarité pour l'enfance, the Fondation du Souffle, the SCOR Corporate Foundation for Science, UK Research and Innovation Future Leader's Fellowship (MR/ S032304/1), the NIHR Imperial Biomedical Research Centre at Imperial College Healthcare NHS Trust (70931), the Burroughs Wellcome Fund Career Awards for Medical Scientists, the Clinical Immunology Society, the American Academy of Allergy Asthma and Immunology, the Michael Smith Foundation for Health Research, the National Health and Medical Research Council of Australia, and the University of New South Wales Sydney COVID Rapid Response Initiative (to S.G. Tangye).