. 2020 Sep 19;22(11):29. doi: 10.1007/s11908-020-00739-6

Table 2.

Diagnostic criteria for multisystem inflammatory syndrome in children

CDC case definition	WHO case definition
• Age < 21 year • Clinical presentation including all of the following: ○ Fever > 38.0 °C for ≥ 24 h, or report of subjective fever lasting ≥ 24 h. ○ Laboratory evidence of inflammation, including, but not limited to: an elevated C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), fibrinogen, procalcitonin, D-dimer, ferritin, lactic acid dehydrogenase (LDH), or interleukin 6 (IL-6), neutrophilia, lymphopenia, and hypoalbuminemia ○ Clinically severe illness requiring hospitalization ○ Multisystem (> 2) organ involvement (cardiac, renal, respiratory, hematologic, gastrointestinal, dermatologic, or neurological) • No alternative plausible diagnoses. • 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 Additional comments • 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	• Age < 19 years • Fever > 3 days • Two of the following: ○ Rash or bilateral non-purulent conjunctivitis or mucocutaneous inflammation signs (oral, hands, or feet) ○ Hypotension or shock ○ Features of myocardial dysfunction, pericarditis, valvulitis, or coronary abnormalities (including ECHO findings or elevated troponin/NT-proBNP) ○ Evidence of coagulopathy (by PT, PTT, elevated d-Dimers) ○ Acute gastrointestinal problems (diarrhea, vomiting, or abdominal pain) • Elevated markers of inflammation such as ESR, CRP, or procalcitonin • No other obvious microbial cause of inflammation, including bacterial sepsis, staphylococcal or streptococcal shock syndromes; AND • Evidence of COVID-19 (RT-PCR, antigen test or serology positive), or likely contact with patients with COVID-19

CDC case definition

WHO case definition

• Age < 21 year

• Clinical presentation including all of the following:

○ Fever > 38.0 °C for ≥ 24 h, or report of subjective fever lasting ≥ 24 h.

○ Laboratory evidence of inflammation, including, but not limited to: an elevated C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), fibrinogen, procalcitonin, D-dimer, ferritin, lactic acid dehydrogenase (LDH), or interleukin 6 (IL-6), neutrophilia, lymphopenia, and hypoalbuminemia

○ Clinically severe illness requiring hospitalization

○ Multisystem (> 2) organ involvement (cardiac, renal, respiratory, hematologic, gastrointestinal, dermatologic, or neurological)

• No alternative plausible diagnoses.

• 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

Additional comments

• 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

• Age < 19 years

• Fever > 3 days

• Two of the following:

○ Rash or bilateral non-purulent conjunctivitis or mucocutaneous inflammation signs (oral, hands, or feet)

○ Hypotension or shock

○ Features of myocardial dysfunction, pericarditis, valvulitis, or coronary abnormalities (including ECHO findings or elevated troponin/NT-proBNP)

○ Evidence of coagulopathy (by PT, PTT, elevated d-Dimers)

○ Acute gastrointestinal problems (diarrhea, vomiting, or abdominal pain)

• Elevated markers of inflammation such as ESR, CRP, or procalcitonin

• No other obvious microbial cause of inflammation, including bacterial sepsis, staphylococcal or streptococcal shock syndromes; AND

• Evidence of COVID-19 (RT-PCR, antigen test or serology positive), or likely contact with patients with COVID-19

CDC Centers for Disease Control and Prevention, WHO World Health Organization, RT-PCR reverse transcription–polymerase chain reaction