Table 1.

MIS-C Case Definitions

	Royal College of Paediatrics and Child Health11	Centers for Disease Control12	World Health Organization13
Fever	Persistent fever >38.5°C	Fever >38.0°C for ≥24 hours, or report of subjective fever lasting ≥24 hours	Fever > 3 days
Evidence of SARS-CoV2 Infection or Exposure	SARS-CoV-2 PCR testing may be positive or negative	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	Evidence of COVID-19 (RT-PCR, antigen test or serology positive), or likely contact with a person with COVID-19
Clinical Features	Inflammation (neutrophilia, elevated CRP and lymphopenia) AND evidence of single or multi-organ dysfunction (shock, cardiac, respiratory, renal, gastrointestinal, or neurological disorder) with additional features	Laboratory evidence of inflammation AND Multisystem (>2) organ involvement (cardiac, renal, respiratory, hematologic, gastrointestinal, dermatologic or neurological)	Elevated markers of inflammation AND Two of the following: Rash/ mucocutaneous signs; Hypotension or shock; Features of myocardial dysfunction, pericarditis, valvulitis, or coronary abnormalities; Coagulopathy; Acute gastrointestinal problems
Alternative Diagnoses	Exclusion of any other microbial cause	No alternative plausible diagnoses	No other obvious microbial cause of inflammation
Level of Care	Not specified	Hospitalization required	Not specified