Figure 2. Cytokine profile of the different groups.

Levels of 34 circulating cytokines were evaluated in serum or plasma. (A) Principal component analysis: every data point represents one individual. (B) Total variance explained by principal component 1 (PC1) and PC2 and variables with higher scores. (C) Representation of canonical variants (Can1 and -2) of the linear discriminant analysis (LDA) built with the cytokines represented in B. (D) Representation of Can2 and Can3 of the LDA (HCs have been removed from the plot, not from the analysis). A “+” indicates subgroup of MIS-C patients differentiated from other MIS-C and KD patients (MIS-C^plus). Open symbols represent patients who previously received immunoglobulin treatment. (E) Heatmap representing the selected cytokines (represented in panel B). Every column represents a patient. An asterisk (*) identifies the cytokines with statically significant differences between KD+MIS-C and MIS-C^plus, and a “+” identifies cytokines with statically significant differences between MIS-C and MIS-C^plus and not with KD. Color gradient represents the z score. KD, pre–SARS-CoV-2 pandemic Kawasaki disease (n = 14); MIS-C, multisystem inflammatory syndrome in children (n = 13); COVID, pediatric patients with mild COVID-19 disease without MIS-C (n = 9); HC, healthy controls (n = 37 [53 samples]).