Multisystem inflammatory syndrome in children

Background

Also known as pediatric inflammatory multisystem syndrome temporally associated with SARS-CoV-2 (PIMS-TS or PIMS)
A syndrome caused by SARS-CoV-2 infection, primarily in children
Characterized by immune dysregulation with multiple systems involved, typically severe and requiring hospitalization

Median age is 7 to 10 years old, but with a range of 1 month to 20 years
Slightly more common in boys than girls
Most common comorbidities are asthma and obesity, though unclear that they are particularly strong risk factors

Children and adolescents aged 0 to 19 years with fever for more than 3 days
AND two of the following:
- Rash or bilateral non-purulent conjunctivitis or muco-cutaneous 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 (diarrhoea, vomiting, or abdominal pain)
AND elevated markers of inflammation such as erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), or procalcitonin
AND no other obvious microbial cause of inflammation, including bacterial sepsis, staphylococcal or streptococcal shock syndromes
AND evidence of the coronavirus disease 2019 (COVID-19) (reverse transcription polymerase chain reaction (RT-PCR), antigen test or serology positive), or likely contact with patients with COVID-19

An individual aged younger than 21 years presenting with fever (greater than 38.0°C for greater than or equal to 24 hours, or report of subjective fever lasting greater than or equal to 24 hours), laboratory evidence of inflammation, and evidence of clinically severe illness requiring hospitalization, with multisystem (more than two) 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 exposure to a suspected or confirmed COVID-19 case within the four weeks prior to the onset of symptoms

A child presenting with persistent fever, 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. This may include children fulfilling full or partial criteria for Kawasaki disease
AND exclusion of any other microbial cause, including bacterial sepsis, staphylococcal or streptococcal shock syndromes, infections associated with myocarditis such as Enterovirus (waiting for results of these investigations should not delay seeking expert advice)
AND SARS-CoV-2 PCR testing may be positive or negative

Persistent fever (higher than 38.0°C for three or more days) and elevated inflammatory markers (CRP, ESR, or ferritin)
AND one of both of the following:
- Features of Kawasaki disease (complete or incomplete)
- Toxic shock syndrome (typical or atypical)
AND no alternative etiology to explain the clinical presentation
AND patients need not have positive SARS-CoV-2 status for consideration