The purpose of this article is to investigate the growing link between COVID-19 and MIS-C, to explore its clinical manifestations and similarity with Kawasaki disease, and to look into prospective treatments. In the end, we provide gaps in literature where further research is required.
The Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection has spread rapidly throughout the world since its discovery in China in late 2019, with epicentres in Europe, India, and the United States. On March 11, 2020, the World Health Organization (WHO) designated COVID-19 as a pandemic disease.  Despite children being least affected initially during the peak of the coronavirus disease 2019 (COVID-19) pandemic, numerous instances of children with hyperinflammatory shock with symptoms similar to Kawasaki disease and toxic shock syndrome were reported in England in April, 2020.  The Centers for Disease Control and Prevention (CDC) issued an online Health Advisory on May 14, 2020, summarising the symptoms of reported multisystem inflammatory syndrome in children (MIS-C), defining a case definition, and urging clinicians to report suspected cases to local and state health departments in the United States. 
"MIS-C was shown to be more common in Hispanic or Latino persons and people of African ancestry"
MIS-C was shown to be more common in specific ethnic groups, such as Hispanic or Latino persons (40.5﹪) and people of African ancestry (33.1﹪), than in non-Hispanic White children in all observational studies conducted in nations like United Kingdom, Rome, Sweden and Russia.  This is in stark contrast to Kawasaki Disease, which is more frequent in East Asian people.  No other comorbidities seemed to implicate incidence, except obesity in children.  Gender seemed to play no role in the disease favouring one over the other five. Diagnostics and treatment options for MIS-C associated with post-COVID-19 infection are restricted due to a lack of evidence on epidemiology, clinical spectrum, and immunological profile.
“ Red flag signs like shortness of breath, which might indicate congestive heart failure or pulmonary embolism, toxic shock-like syndrome,or a cytokine storm were the most concerning.”
All of the children had serologic evidence of SARS-CoV-2 infection, and their signs and symptoms were related to COVID-19, despite the fact that they appeared 3-4 weeks after the viral infection. The initial symptoms consisted of fever, rash, conjunctivitis, peripheral edema, shock, and elevated inflammation.  Red flag signs like shortness of breath, which might indicate congestive heart failure or pulmonary embolism, toxic shock-like syndrome,or a cytokine storm were the most concerning.  Children also presented with abdominal discomfort, diarrhoea, nausea/vomiting, and other gastrointestinal symptoms (patients have presented with colitis, hepatitis, and probable appendicitis). Some cases of acute kidney injury were also seen,and thrombophilia was not uncommon. 
MISC AND KAWASAKI
Conjunctival injection, edema of the hands and feet and mucosal inflammation are typical clinical symptoms of both Kawasaki Disease and MIS-C.  Abdominal pain and cardiovascular malfunctions such as coronary artery dilation, ventricular dysfunction, valvular regurgitation, and hypotension are all symptoms unique to MIS-C.  MIS-C symptoms are more similar to Kawasaki disease shock syndrome (KDSS).  In comparison to children with KD, patients with KDSS have more band cells in peripheral smear and higher C-reactive protein levels, as well as decreased hemoglobin and platelet counts. Furthermore, KDSS and MIS-C patients have a greater rate of coronary artery dilatation and cardiac dysfunction which heightens the similarities between them. 
Regimens for adult patients have been developed by physicians at various centers based on particular symptoms, past therapy of comparable illnesses such as Kawasaki disease, or COVID-19 treatment recommendations. In MIS-C confirmed or suspected cases, a multidisciplinary team approach involving a pediatric infectious diseases unit, cardiology, immunology, rheumatology, and intensive care unit teams are involved. Antiviral therapy should be considered in serologically positive COVID-19 patients. It is critical to provide general supportive care, with specific focus on vital signs, hydration, electrolytes, and metabolic state.  Although few children show signs of respiratory impairment or hypoxia, they should be constantly observed for any signs of compromise.  The majority of the children who are afflicted with MIS-C also receive intravenous immune globulin (IVIG), with some receiving high-dose steroids as well. Few children require further treatments, such as Anakinra (recombinant IL-1 antagonist) or a second dose of IVIG, after responding positively to initial therapy. 
GAPS IN LITERATURE
" Further research, in terms of periodic studies, is needed to better understand who is susceptible to MIS-C and how to prevent MIS-C in people infected with COVID-19."
Several research studies have been conducted to describe the pathogenesis, diagnostic characteristics, and treatment of MIS-C. WHO, CDC, and AAP have all published protocols and guidelines based on substantial studies. [1,3,7] Diagnostic protocols and treatment options for MIS-C associated with COVID-19 infection are still being developed due to ever-evolving evidence on its epidemiology, clinical spectrum, and immunological profile. This comprehensive mini review highlights the clinical picture of MIS-C, current thoughts on clinical and immunological distinction from Kawasaki Disease, and possible treatment approaches. Further research, in terms of periodic studies, is needed to better understand who is susceptible to MIS-C and how to prevent MIS-C in people infected with COVID-19.
Author : Dr. Avanthika Chaithanya
Editor : Dr. Purva Shah