Absence of correlation between sC5b9 elevatons and antibodies against SARS-CoV-2. Correlation between sC5b9 vs the logarithmically transformed value of IgG (A), IgM (B), and IgA (C) against the SARS-CoV-2 RBD protein for a subset of included patients with MIS-C (n = 10), severe disease (n = 11), and minimal disease (n = 12).