Multisystem inflammatory syndrome in kids with COVID-19: Clinical profile and outcomes

Multisystem inflammatory syndrome (MIS) in critically ill children with the coronavirus disease 2019 (COVID-19) is more varied than previously thought, according to a new study. Despite this, complete recovery appears to be almost universal.

“The detailed clinical profile, therapies, interventions, and outcomes in children with MIS (MIS-C) from the United States are lacking,” researchers said. “We report a multicentre cohort of children with COVID-19-associated MIS-C from the epicenter of COVID-19 in New York City, describing the spectrum of clinical presentation, hospital course, therapies, and outcomes.”

Thirty-three MIS-C patients (median age, 10 years; 61 percent male) were included, although most (81 percent) tested positive for COVID-19 using only antibody tests. Nearly half of the patients had comorbid conditions and almost all presented with fever. [J Pediatr 2020;224:24-29]

In terms of laboratory parameters, participants showed elevated levels of inflammatory markers such as the C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), ferritin, and procalcitonin. Indicators of abnormal cardiac status—including B-type natriuretic peptide (BNP), N-terminal pro-BNP, and troponin—were likewise heightened.

Imaging and echocardiogram results demonstrated that MIS-C manifested heterogeneously. Ten patients (30 percent) had cardiomegaly, and 11 (33 percent) showed focal or bilateral pulmonary opacities.

Twenty-one patients (65.6 percent) had lowered left ventricle ejection fraction (LVEF), of whom four had a value <30 percent. Notably, upon a second echocardiogram, all but one of these patients showed recovery of ventricular function and normalization of EF.

Five patients (15 percent) ultimately needed to be put on invasive mechanical ventilation, and two (6 percent) required mechanical circulatory support by extracorporeal membrane oxygenation (ECMO) or by an intra-aortic balloon pump (IABP).

Both patients on circulatory support had severely impaired LV function. The patient on IABP was also treated with methylprednisolone and convalescent plasma and was discharged home by day 12. The patient on ECMO also had concomitant cardiogenic shock but eventually developed ischaemic brain infarction with subarachnoid haemorrhage. Life-sustaining medications were terminated after the determination of brain death.

All other patients survived to discharge, with a median stay of 4.7 days in intensive care and 7.8 days in the hospital.

“The clinical profile of COVID-19 MIS-C in our cohort of 33 children was heterogeneous in severity of illness, ranging from clinically stable patients with normal or mildly depressed myocardial function to decompensated circulatory shock requiring invasive mechanical ventilation and mechanical circulatory support,” the researchers said.

“Further larger multicentre studies are needed to further elucidate the spectrum of disease, risk factors for more severe illness, and response to supportive and medical therapies including [intravenous immunoglobulins], corticosteroids, biologic modifying agents, and anticoagulation strategies. Long-term follow-up will be required to determine any sequelae of MIS-C on myocardial function,” they added.