COVID-19, Autoantibodies, and Multisystem Inflammatory Syndrome in Children

February 23, 2021

Throughout the pandemic, cases have been reported of children experiencing a hyper-inflammatory response after a COVID-19 infection (1, 2). What was first described as a cluster of intense symptoms, has since come to be known as Multisystem Inflammatory Syndrome in Children (MIS-C). 

The pool of data around SARS-CoV-2 infection and MIS-C is still small, and a lack of consistency in clinical presentations of MIS-C makes it easy for clinicians to misdiagnose symptoms for other conditions where hyper inflammation is prevalent, like Kawasaki disease, toxic shock syndrome, and macrophage-activation syndrome (MAS). Due to the general ambiguity around MIS-C’s cause and development, as well as its mechanisms for tissue damage, the CDC and WHO have constructed different clinical criteria for the diagnosis of MIS-C (3).

The American Academy of Pediatrics (AAP) recently published the results of an international survey detailing MIS-C cases from April-June 2020. Data was provided from 33 hospitals and included 183 pediatric patients ages 1.2 months to 18 years. In the clinical presentations of MIS-C, all patients presented with a fever (>100.4 F), and over 60% had gastrointestinal symptoms. The second most common symptom was cardiovascular. These findings coincide with previously published reports and classification criteria for MIS-C; other common clinical manifestations include dermatologic/ mucocutaneous symptoms, cardiovascular symptoms, respiratory symptoms, and neurologic symptoms (4). Examples can include rash, swelling of hands and/or feet, change to the oral mucosa, pink eye, and swollen lymph nodes. It is unknown why a hyperimmune response occurs, and why autoantibodies against endothelial, gastrointestinal, and immune cells are produced. One study conducted by the Icahn School of Medicine found that MIS-C may share some pathophysiology with autoimmune disease. 
114 of the 183 patients included in the AAP survey tested positive for current or recent SARS-CoV-2 infection (3). Patients who did not test positive for COVID but presented symptoms concurrent to MIS-C may have experienced a COVID-19 exposure 2-6 weeks prior to the onset of symptoms (4). 

Continued research studying this occurrence will help to shed light on the long-standing damage this hyperimmune response may have on the body. Additionally, as criteria for clinical diagnosis is standardized, children experiencing MIS-C can have more immediate access to tailored therapies and treatment, to mitigate the often severe symptoms that accompany MIS-C. 





Join Our Community!Stay Informed. Stay Hopeful.

Sign up for periodic emails with resources, insights, and updates on autoimmune disease and living with chronic illness.

By adding your phone number, you agree to receive text message updates. Msg & data rates may apply.