In AOSD, IL-18 is elevated in the serum, lymph node, skin eruptions, and synovial membranes (67, 69, 87, 88), and the level of IL-18 is correlated with serum ferritin values, hepatitis severity, disease severity, and disease activity (69, 70, 89, 90). This evidence concerns the gene IL18 and adult-onset Still disease.