Abstract 11811: Cardiac Biomarkers Differentiate Kawasaki Disease From Multisystem Inflammatory Syndrome in Children Associated With Covid-19

Abstract

Introduction: Kawasaki disease (KD) and Multisystem Inflammatory Syndrome in Children (MIS-C) associated with COVID-19 show considerable clinical overlap making differentiation challenging. Hypothesis: Cardiac biomarkers can differentiate KD from MIS-C. Methods: The International KD Registry enrolled 2566 contemporaneous KD, MIS-C and acute COVID-19 pediatric patients from 39 sites in 8 countries from January 2020 through January 2022. The study population included MIS-C patients meeting CDC criteria with confirmed or probable COVID-19 infection, and KD patients meeting AHA guideline criteria without COVID-19 infection. Included patients had to have at least one measurement of NTproBNP or troponin I. KD and MIS-C patients were compared, to assess factors associated with cardiac biomarkers and cardiac outcomes. Receiver operating characteristic curves were used to determine cut points differentiating KD from MIS-C. Results: Of 779 patients with KD, 168 had NTproBNP (median 381 ng/L) and 173 had troponin I (median <10 ug/L) assessed at presentation, while of 1207 patients with MIS-C, 427 had NTproBNP (median 1850 ng/L; p<0.001 vs KD) and 522 had troponin I (median 12.7 ug/L; p<0.001) assessed. Baseline NTproBNP and troponin were correlated mildly (r=0.09; p=0.05) and were associated with older age and higher creatinine levels. Lower LV ejection fraction (LVEF) was associated with MIS-C (vs KD), but not with baseline or peak troponin levels after adjusting for age and creatinine levels. Lower LVEF was significantly associated with higher baseline and peak NTproBNP levels after adjusting for diagnosis and age. Higher peak coronary artery Z score was associated with KD vs MIS-C, but neither cardiac biomarker. Baseline troponin I >10 ug/L predicted MIS-C vs KD with a sensitivity of 57% and specificity of 74% (c-statistic 0.61), and baseline NTproBNP >1600 ng/L with a sensitivity of 54% and specificity of 75% (c-statistic 0.69). Conclusions: Higher baseline troponin I and NTproBNP levels are more predictive of MIS-C compared to KD. Lower LVEF, more common with MIS-C, was associated with higher NTproBNP but not troponin I levels, and coronary artery involvement, more common in KD, was not associated with either cardiac biomarker.