In KD, coronary artery aneurysms or dilation and pericardial effusion are most common, whereas depressed ventricular function and highly elevated brain-natriuretic peptide (BNP) are more typical of MIS-C.29 Some patients with MIS-C have developed coronary artery dilation and aneurysms, although most of these patients have had complete resolution of the abnormalities at follow-up,30 as opposed to KD where a subset of patients have persistent coronary artery abnormalities. Here, NPPB is linked to aneurysm.