Starting in late April, clinicians in several countries, including the eastern United States, have reported several dozen cases of children presenting with a severe inflammatory syndrome with a laboratory-confirmed case of COVID-19 or an epidemiological link to a COVID-19.
The inflammatory disease is called multisystem inflammatory syndrome in children (MIS-C) associated with coronavirus disease 2019 (COVID-19). It has some similarities to Kawasaki disease, an illness that is most common in young children, as well as some characteristics of toxic shock syndrome. Some of the presenting features include those of Kawasaki syndrome such as rash, conjunctival inflammation, prolonged fever, mucosal changes and extremity edema.
Case definition for multisystem inflammatory syndrome in children (MIS-C) from the CDC
- An individual aged <21 years presenting with feveri, laboratory evidence of inflammationii, and evidence of clinically severe illness requiring hospitalization, with multisystem (>2) organ involvement (cardiac, renal, respiratory, hematologic, gastrointestinal, dermatologic or neurological); AND
- No alternative plausible diagnoses; AND
- Positive for current or recent SARS-CoV-2 infection by RT-PCR, serology, or antigen test; or COVID-19 exposure within the 4 weeks prior to the onset of symptoms
iFever >38.0°C for ≥24 hours, or report of subjective fever lasting ≥24 hours iiIncluding, but not limited to, one or more of the following: an elevated C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), fibrinogen, procalcitonin, d-dimer, ferritin, lactic acid dehydrogenase (LDH), or interleukin 6 (IL-6), elevated neutrophils, reduced lymphocytes and low albumin
Additional comments from the CDC:
- Some individuals may fulfill full or partial criteria for Kawasaki disease but should be reported if they meet the case definition for MIS-C
- Consider MIS-C in any pediatric death with evidence of SARS-CoV-2 infection
The Children’s Hospital Colorado Scientific Advisory Council on COVID-19 is developing a clinical care guidance for MIS-C based on local and international expertise and the evolving evidence on this condition. For questions about potential patients with this condition, please call our Infectious Disease team via OneCall (720-777-3999 in Denver Metro or 719-305-3999 in Colorado Springs).
Download a PDF from the Royal College of Paediatrics and Child Health Guidance for more information on MIS-C.
Is MIS-C related to COVID-19?
We still don’t know if multisystem inflammatory syndrome in children is related to the coronavirus. There is a strong association between MIS-C and COVID-19 in terms of timing as well as geographical association. There is a suggestive relationship between the two; however, this a new and evolving situation that we continue to monitor and learn more about.
What separates MIS-C from COVID-19?
A child can just have COVID-19 but not MIS-C. Some of the children who have been reported to have MIS-C have tested positive for COVID-19, and others have not.
Many large children’s hospitals in the U.S. have not reported MIS-C because it is very rare – despite seeing high numbers of cases of COVID-19.
Listen to our Charting Pediatrics podcast where pediatric experts discuss MIS-C.