Diagnosis delay is associated with heart failure severity in multisystem inflammatory syndrome in children

Abstract

Diagnosis delay leads to an increased risk of coronary artery aneurysms in Kawasaki disease. In multisystem inflammatory syndrome in children (MIS-C), diagnosis delay could worsen heart failure. This study aims to test the hypothesis that a long time to diagnosis is associated with heart failure severity in MIS-C. A retrospective single-center observational study was conducted between May 2020 and April 2022. Children with a MIS-C diagnosis meeting WHO criteria were included. A long time to diagnosis was defined as 6 days or more. Outcomes were assessed on severity of heart failure, including peak NT-proBNP, minimal left ventricular ejection fraction (LVEF) and need for inotropes (dobutamine, milrinone, adrenaline). Thirty-two children were included in the study. One child was excluded due to previous vaccination against COVID-19. The median age [1st–3rd interquartile range] was 8 [5–10] years old. The median time to diagnosis was 5.3 [4.0–6.3] days. Children with a long time to diagnosis ( n = 13), compared with those with a short time to diagnosis ( n = 18), had a higher peak NT-proBNP (22304 [13859–47889] ng/L versus 5555 [2384–10227] ng/L, respectively, P < 0.001), lower LVEF (40 [30–50] % versus 45 [45-55,5] %, respectively, P = 0.02), and were more often treated with inotropes (8 children (57%) versus 0 child (0%) respectively, P < 0.001). Diagnosis delay is associated with heart failure severity in MIS-C. Early diagnosis and treatment are crucial to avoid the use of inotropes and limit morbidity.