Corticosteroids superior to intravenous IG in MIS-C myocardial damage due to COVID-19

Treatment with corticosteroids (CS) among children with multisystem inflammatory syndrome (MIS-C) cardiovascular involvement temporarily associated with COVID-19 leads to faster normalization of left ventricular ejection fraction (LVEF), fever, improved laboratory analysis, and shorter intensive care unit stay than treatment with intravenous immunoglobulin (IVIG), a study has shown.

“CS should also be used for refractory MIS-C because after CS was added, patients became afebrile, the C-reactive protein (CRP) value dropped, and the sodium and phosphate levels increased significantly,” the researchers said. “The short-term sequelae of MIS-C and CS side-effect were reversible in our study.”

This retrospective cohort study included 19 patients with acute LV systolic dysfunction associated with MIS-C, mean age of 13.2±3.8, and treated from April 2020 to April 2021. Participants were treated with IVIG or CS.

Eight patients had treatment failure: seven out of 10 in the IVIG group and one out of nine in the CS group. Additionally, IVIG treatment was independently associated with a higher risk of treatment failure (odds ratio, 18.6, 95 percent confidence interval, 1.6–222.93; p=0.02). [Pediatr Infect Dis J 2021;40:e390-e394]

For patients initially treated with CS, fever improved during in-hospital day 1 (1.5 days, interquartile range [IQR], 1–2), whereas those treated with IVIG became afebrile on day 4 (IQR, 2–4.25), after CS was added. CRP significantly decreased on day 2 among CS-treated patients (p=0.01) and on day 4 in the IVIG group (p=0.04). Sodium and albumin levels were higher on in-hospital day 3 in the CS group (p=0.015) than in the IVIG group (p=0.03).

Furthermore, patients in the CS group had significant improvement and normalization of EF during the first 3 days (p=0.005). ICU stays were also shorter in the CS group (4 days, IQR, 2–5.5) than in the IVIG group (7 days, IQR, 6–8.5; p=0.002).

“Some studies have shown that 51–80 percent of patients with MIS-C did not respond to IVIG treatment, while 70 percent of our patients with MIS-C appear to be unresponsive to IVIG,” the researchers said. “CS was added to this group’s therapy on day 3 on average.” [JAMA 2021;325:855-864; Lancet 2020;395:1771-1778]

Immediately after CS introduction to these patients on day 4 of in-hospital stay, serum levels of sodium and phosphate markedly increased, CRP substantially decreased, and patients became afebrile.

“Patients treated with CS had a faster normalization of body temperature, heart rate, and systolic pressure than patients treated with IVIG and a rapid decline in pro-inflammatory parameters in the blood,” the researchers said. “Compared with the IVIG group, CS-treated patients had a lower CRP on day 4, but higher sodium, albumin, and phosphate levels.

A previous study also showed that IVIG in combination with CS resulted in shorter cardiac function recovery time in patients with MIS-C. [Circulation 2020;142:2282-2284]

The current study was limited by its retrospective design, small sample size, and insufficient follow-up period to draw conclusions.