Long-term outcomes of MIS-C

A research letter offers some of the first data on the long-term outcomes of the first children diagnosed with multisystem inflammatory syndrome in children (MIS-C).

It’s been over a year since multisystem inflammatory syndrome in children was first identified and linked to COVID-19. The medium- to long-term outcomes of the condition are unknown. A research letter offers some of the first data on those outcomes among children in the United Kingdom.1

The investigators collected follow-up data for a previously published cohort that had been admitted to the hospital before May 2020. This data included critical care readmissions and outpatient follow-up clinics up to April 2021. Cardiological normal values were values were locally defined and the frequency of monitoring was left up to the discretion of individual units.

Of the 76 patients in the initial cohort, 68 had available data. No deaths occurred in the cohort and 2 needed critical care readmission. Neither admission was related to complications of multisystem inflammatory syndrome in children or immunomodulatory therapy. The median length of the hospital stay was 10 days and no one needed respiratory support following discharge. After more than 50 days postadmission, abnormal results occurred in only 2 of 65 test results for C-reactive protein, 2 of 59 test results for D-dimer, and 1 of 60 test results for troponin and all blood tests for levels of lymphocytes, neutrophils, platelets, creatinine, ferritin, and alanine transaminase were normal. Among the patients who presented with aneurysms, 14 of 19 had resolution and among those with subjectively “bright” coronary arteries, 9 of 10 had resolution and 1 progressed to unresolved coronary artery aneurysms. By day 74, all patients who presented with impaired function without aneurysm had recovered. There were 6 patients with ongoing echocardiographic abnormalities, with all receiving intravenous immunoglobulin; 5 of 6 receiving steroids; and 1 of 6 receiving a biologic agent.

The investigators concluded that some patients with multisystem inflammatory syndrome in children are at risk for significant long-term morbidity. However, for the majority of patients, outcomes are generally good, with little to no significant medium- or long-term sequelae.

Reference

1. Davies P, du Pré P, Lillie J, Kanthimathinathan H. One-year outcomes of critical care patients post–COVID-19 multisystem inflammatory syndrome in children. JAMA Pediatr. August 30, 2021. Epub ahead of print. doi:10.1001/jamapediatrics.2021.2993