Study population and setting
This report included patients meeting criteria for multisystem inflammatory syndrome in children (MIS-C) associated with SARS-CoV-2 infection from 106 hospitals providing pediatric care in New York State that were required to report such cases to the New York State Department of Health (NYSDOH). Confirmed cases were those who met both clinical and laboratory criteria; laboratory evidence required: 1) at least two elevated inflammatory biomarkers, and 2) either virologic or serologic evidence for current or prior SARS-CoV-2 infection within 10 days of admission. Suspected cases were those lacking laboratory evidence of infection but with exposure to a known case of COVID-19 within 6 weeks of admission. Between March 1 and May 10, 2020, 191 possible cases younger than 21 years of age were reported to NYSDOH; 95 patients met the case definition for confirmed MIS-C and 4 patients were categorized as suspected MIS-C.
Summary of Main Findings
Of the 95 patients meeting the confirmed case definition for MIS-C, 76/77 (99%) tested for SARS-CoV-2 IgG antibodies were positive and 50/94 (53%) tested with RT-PCR assay were positive. Suspected MIS-C cases had negative molecular testing, and did not undergo serologic testing. 31% of patients were 0-5 years of age, 42% were 6-12 years of age, and 26% were 13-20 years of age. 36% of patients had a pre-existing comorbidity, 29% with obesity. All patients presented with fever and chills; other presenting symptoms included gastrointestinal (80%), dermatologic (62%), mucocutaneous (61%), and respiratory (40%). At admission, 97% of patients had tachycardia, 78% had tachypnea, and 32% had hypotension. Nearly half of patients 12 and younger presented with symptoms of Kawasaki disease, but only 12% of those 13 and older did so. 24% of patients had previously experienced illness consistent with COVID-19, at a median of 21 days before admission. Only two patients had laboratory evidence of other respiratory viral infection, both of whom also tested positive for SARS-CoV-2. 80% of patients were admitted to the ICU, and 10% required mechanical ventilation. Common treatments included intravenous immune globulin (70%), glucocorticoids (64%), and vasopressor support (62%). 51 of 93 (55)% patients with echocardiograms had ventricular dysfunction, 32% had pericardial effusion, and 9% had a coronary artery aneurysm. 59 of 60 (98%) patients with available data had cardiac abnormalities, and 34 of 44 (77%) patients with abdominal CT scans had abnormal results. By the end of follow-up on May 15, 76 patients had been discharged alive, 21 patients were still hospitalized, and 2 patients had died. The median length of hospitalization was 6 days for those discharged alive and 7 days for those who died.
This study benefited from mandatory reporting of cases by hospitals in New York State, a consistent case definition, and detailed characterization of patients.
Case definitions may have resulted in under-ascertainment: laboratory evidence of SARS-CoV-2 infection may be limited by false negative results or lack of test availability; similarly, inflammatory biomarker assays may not have been available for other possible cases. The lack of a comparison group precludes inference about risk factors. Follow-up was incomplete for the 21% of patients still hospitalized.
This study adds to the evidence supporting a distinct hyperinflammatory syndrome in children that follows SARS-CoV-2 infection, and helps to make the case for MIS-C surveillance in regions with high incidence of COVID-19.
This review was posted on: 10 July 2020