Characteristics and Outcomes of US Children and Adolescents With Multisystem Inflammatory Syndrome in Children (MIS-C) Compared With Severe Acute COVID-19

Abstract

IMPORTANCE Refinement of criteria for multisystem inflammatory syndrome in children (MIS-C) may inform efforts to improve health outcomes. OBJECTIVE To compare clinical characteristics and outcomes of children and adolescents with MIS-C vs those with severe coronavirus disease 2019 (COVID-19). SETTING, DESIGN, AND PARTICIPANTS Case series of 1116 patients aged younger than 21 years hospitalized between March 15 and October 31, 2020, at 66 US hospitals in 31 states. Final date of follow-up was January 5, 2021. Patients with MIS-C had fever, inflammation, multisystem involvement, and positive severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) reverse transcriptase-polymerase chain reaction (RT-PCR) or antibody test results or recent exposure with no alternate diagnosis. Patients with COVID-19 had positive RT-PCR test results and severe organ system involvement. EXPOSURE SARS-CoV-2. MAIN OUTCOMES AND MEASURES Presenting symptoms, organ system complications, laboratory biomarkers, interventions, and clinical outcomes. Multivariable regression was used to compute adjusted risk ratios (aRRs) of factors associated with MIS-C vs COVID-19. RESULTS Of 1116 patients (median age, 9.7 years; 45% female), 539 (48%) were diagnosed with MIS-C and 577 (52%) with COVID-19. Compared with patients with COVID-19, patients with MIS-C were more likely to be 6 to 12 years old (40.8% vs 19.4%; absolute risk difference [RD], 21.4% [95% CI, 16.1%-26.7%]; aRR, 1.51 [95% CI, 1.33-1.72] vs 0-5 years) and non-Hispanic Black (32.3% vs 21.5%; RD, 10.8% [95% CI, 5.6%-16.0%]; aRR, 1.43 [95% CI, 1.17-1.76] vs White). Compared with patients with COVID-19, patients with MIS-C were more likely to have cardiorespiratory involvement (56.0% vs 8.8%; RD, 47.2% [95% CI, 42.4%-52.0%]; aRR, 2.99 [95% CI,] vs respiratory involvement), cardiovascular without respiratory involvement (10.6% vs 2.9%; RD, 7.7% [95% CI, 4.7%-10.6%]; aRR, 2.49 [95% CI, 2.05-3.02] vs respiratory involvement), and mucocutaneous without cardiorespiratory involvement (7.1% vs 2.3%; RD, 4.8% [95% CI, 2.3%-7.3%]; aRR, 2.29 [95% CI, 1.84-2.85] vs respiratory involvement). Patients with MIS-C had higher neutrophil to lymphocyte ratio (median, 6.4 vs 2.7, P < .001), higher C-reactive protein level (median, 152 mg/L vs 33 mg/L; P < .001), and lower platelet count (<150 ×10 3 cells/μL [212/523 {41%} vs 84/486 {17%}, P < .001]). A total of 398 patients (73.8%) with MIS-C and 253 (43.8%) with COVID-19 were admitted to the intensive care unit, and 10 (1.9%) with MIS-C and 8 (1.4%) with COVID-19 died during hospitalization. Among patients with MIS-C with reduced left ventricular systolic function (172/503, 34.2%) and coronary artery aneurysm (57/424, 13.4%), an estimated 91.0% (95% CI, 86.0%-94.7%) and 79.1% (95% CI, 67.1%-89.1%), respectively, normalized within 30 days.CONCLUSIONS AND RELEVANCE This case series of patients with MIS-C and with COVID-19 identified patterns of clinical presentation and organ system involvement. These patterns may help differentiate between MIS-C and COVID-...

Mental health of Adolescents in the Pandemic: Long-COVID19 or Long-Pandemic Syndrome?

“…While multiple studies and registers have provided reliable data on epidemiology, clinical presentation, disease course and treatment options on PIMS [7][8][9] to date no comparable data exists for Long-COVID19 in children and adolescents. A cross-sectional study from Italy 10 in 123 children diagnosed with a SARS-CoV-2 infection found that more than 50% of participants had at least one persisting symptom 120 days after their infection, with Insomnia, pain, fatigue, and concentration difficulties being the most commonly reported ones.…”

Clinical and laboratory findings of multisystem inflammatory syndrome in children (MIS-C) below age 1

“…All cases mentioned in the article are above the age of 1. There are a limited number of publications regarding the clinical course and laboratory findings of MIS-C in cases below age 1 [2]. While other age groups may exhibit typical symptoms such as fever, rash, respiratory distress, and gastrointestinal symptoms, cases below the age of 1 may present with more uncommon symptoms such as febrile convulsion, persistent pulmonary hypertension and coronary artery aneurysm.…”

What are the risk factors for admission to the pediatric intensive unit among pediatric patients with COVID-19?

“…Among these is heart involvement [16]. Several findings seem to indicate that, in the first phases of severe COVID-19, signs and symptoms of heart lesions can occur and be useful to select children at risk for complications [13,17,18]. A great number of previously healthy children with MIS-C present with cardiovascular alterations [19][20][21].…”

“…A great number of previously healthy children with MIS-C present with cardiovascular alterations [19][20][21]. Some of them already have signs and symptoms of heart dysfunction in the first phases of disease, and it has been reported that they increase the need for PICU admission, development of potential long-term problems, and risk of death [13,17,18]. Reduced left ventricular systolic function with an ejection fraction < 60%; diastolic dysfunction; and arrhythmias, including ST segment changes, QTc prolongation, and premature atrial or ventricular beat, were the earliest manifestations.…”

“…Reduced left ventricular systolic function with an ejection fraction < 60%; diastolic dysfunction; and arrhythmias, including ST segment changes, QTc prolongation, and premature atrial or ventricular beat, were the earliest manifestations. Moreover, increased troponin levels have been repeatedly reported in children with COVID-19 admitted to the PICU [13,18,19]. Inclusion of heart enzyme serum levels and evaluation of ventricular function among predictive markers could lead to a more effective evaluation of children at risk with proper selection of those to admit to the PICU and with more adequate treatment in case of more severe clinical manifestations.…”