By six months post-discharge, 99% of children and young adults diagnosed with multisystem inflammatory syndrome in children had normalized left ventricular systolic function, and 92.3% had normalized coronary artery dimensions, according to a recent cohort study published.
The study, in JAMA Pediatrics, followed 1,204 participants under 21 years old who were hospitalized with multisystem inflammatory syndrome in children (MIS-C) between March 2020 and January 2022, across 32 North American pediatric hospitals. Among the 15 participants with coronary artery aneurysms (z score ≥2.5), 92.3% showed resolution by six months, while one participant retained a large/giant aneurysm.
Most participants demonstrated significant improvements in overall health. By six months, 95.1% reported being at least 90% back to their pre-MIS-C baseline across domains such as energy, sleep, appetite, cognition, and mood. Fatigue prevalence decreased from 15.9% at two weeks to 3.4% by six months. PROMIS Global Health T scores for fatigue, pain interference, and overall health improved significantly, reaching or exceeding pre-pandemic norms.
The cohort included a diverse population, with 27% identifying as non-Hispanic Black and 26.9% as Hispanic. Pre-existing conditions were reported in 32.5% of participants, with asthma being the most common (9%).
During hospitalization, 45.9% of participants required vasoactive support, and 1.4% needed extracorporeal membrane oxygenation. The mortality rate was low, at 0.3%, with three deaths reported.
Neurological symptoms, such as headaches impacting activities, were reported in 5.6% of participants at two weeks but decreased to 4.1% by six months.
“The longer-term health implications of MIS-C are unknown,” said Dongngan Truong, MD, lead author. “Continued surveillance of participants is ongoing to characterize their health status up to two years after illness onset.”
Despite its observational nature and limited echocardiographic review due to budget constraints, the study provides encouraging evidence of recovery among most children and adolescents with MIS-C.
Full disclosures can be found in the study.
