Emergency department levels of NT-proBNP and inotropic/vasoactive support in multi-inflammatory syndrome in children (MIS-C)

Background: Multisystem inflammatory syndrome in children (MIS-C) is an uncommon COVID-19 related severe hyperinflammatory condition. Some of these patients develop cardiac dysfunction that may require vasopressor/inotropic support. Increased levels of cardiac N-terminal pro-brain natriuretic peptide (NT-proBNP) have been shown to be associated with cardiac dysfunction. Levels of NT-proBNP drawn at the time of ED presentation of MIS-C patients have not yet been described.

Methods: We retrospectively reviewed all cases of MIS-C admitted to the pediatric ED of a tertiary medical center between 01/03/2020 and 31/05/2021.

Results: Fourteen patients were diagnosed with MIS-C during the study period, 8 required inotropic/vasoactive support. Four patients were treated with an inotropic medication only; these patients had NT-proBNP levels of 7,309 pg/ml or lower, normal cardiac function or mild cardiac dysfunction on echocardiography, and ICU length of stay of 3-6 days. Four patients were treated with inotropic and vasoactive medications; these patients had NT-proBNP levels of 15,901pg/ml or higher, mild or moderate cardiac dysfunction on echocardiography, and ICU length of stay of 7-10 days. No patient required ECMO support. Pre-discharge echocardiography revealed normal cardiac function for all patients.

Discussion: Study results suggest that ED levels of NT-proBNP can serve as early warning indicators for the requirement of inotropic support in MIS-C. The findings raise the possibility that, if a high NT-proBNP level is detected, a more severe disease course is expected and early administration of inotropic medications may be required.