During hospitalization (days after admission), patients with MIS-C had significantly higher peak levels of D-dimer, C-reactive protein (CRP), troponin I (TnI), and pro–B-type natriuretic peptide (proBNP), as well as lower nadirs of lymphocytes and platelets, compared with patients with pCOVID-19 (P < 0.05 for all). The gene discussed is CRP; the disease is COVID-19–associated multisystem inflammatory syndrome in children.