In this post, I link to three recent articles on Multisystem Inflammatory Syndrome In Children (MIS-C) that I reviewed today.

  • Multisystem inflammatory syndrome in children (MIS-C): a mini-review [PubMed Abstract] [Full-Text HTML] [Full-Text PDF]. Int J Emerg Med. 2021 Sep 10;14(1):50.
    • "Abstract
      Multisystem inflammatory syndrome in children (MIS-C) is a novel, life-threatening hyperinflammatory condition that develops in children a few weeks after infection with severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). This disease has created a diagnostic challenge due to overlap with Kawasaki disease (KD) and KD shock syndrome. The majority of patients with MIS-C present with the involvement of at least four organ systems, and all have evidence of a marked inflammatory state. Most patients show an increase in the level of at least four inflammatory markers (C-reactive protein, neutrophil count, ferritin, procalcitonin, fibrinogen, interleukin-6, and triglycerides). Therapy is primarily with immunomodulators, suggesting that the disease is driven by post-infectious immune dysregulation. Most patients, even those with severe cardiovascular involvement, recover without sequelae. Since coronary aneurysms have been reported, echocardiographic follow-up is needed. Further study is needed to create uniform diagnostic criteria, therapy, and follow-up protocols."
  • Current Understanding of Multisystem Inflammatory Syndrome (MIS-C) Following COVID-19 and Its Distinction from Kawasaki Disease [PubMed Abstract] [Full-Text HTML] [Full-Text PDF]. Curr Rheumatol Rep. 2021; 23(8):  58.Published online 2021 Jul 3
    • "Abstract                                                                                                        Purpose of review: In this article, I have reviewed current reports that explore differences and similarities between multisystem inflammatory syndrome in children (MIS-C) and other known multisystem inflammatory diseases seen in children, particularly Kawasaki disease.Recent findings: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a human coronavirus causing the COVID-19 disease which emerged in China in December 2019 and spread rapidly to the entire country and quickly to other countries. Currently, there is a pandemic of SARS-CoV-2 infection that results in 20% of patients admitted to hospital with illness, with 3% developing intractable acute respiratory distress syndrome (ARDS) with high mortality. However, pediatric COVID-19 is still reported to be a mild disease, affecting only 8% of children. Pathogenesis in children is comparable to adults. There are suggested impaired activation of IFN-alpha and IFN regulator 3, decreased cell response causing impaired viral defense, yet the clinical course is mild, and almost all children recover from the infection without major complications. Interestingly, there is a subset of patients that develop a late but marked immunogenic response to COVID-19 and develop MIS-C. Clinical features of MIS-C resemble certain pediatric rheumatologic diseases, such as Kawasaki disease (mucocutaneous lymph node syndrome) which affects small-medium vessels. Other features of MIS-C resemble those of macrophage activation syndrome (MAS). However, recent research suggests distinct clinical and laboratory differences between MIS-C, Kawasaki disease, and MAS. Since the start of the SARS-CoV-2 pandemic, MIS-C has become the candidate for the most common cause of acquired heart disease in children.

      Keywords: COVID-19; Kawasaki; MIS-C; Macrophage activation syndrome (MAS); SARS-CoV2."