In total, we identified eight upregulated hub genes in patients with active SJIA: HP, MPO, MMP8, MMP9, ARG1, OLFM4, DEFA4, and PGLYRP1. We postulate these genes to be significantly involved in the inflammatory environment and subsequent disease progression in patients with active SJIA. This evidence concerns the gene MPO and systemic-onset juvenile idiopathic arthritis.