IL-31 significantly correlates with disease activity and Th2 cytokine levels in children with atopic dermatitis.

Recently, we could show that IL-31 serum levels are significantly increased in adult patients with atopic dermatitis compared with skin healthy controls. However, the regulation of IL-31 in children with atopic dermatitis so far is not clear. Thus, we analyzed IL-31 serum levels together with IL-4, IL-13, ECP, and total IgE levels in 60 children with extrinsic, in five children with intrinsic atopic dermatitis, and 20 non-atopic healthy children. Further, we determined the SCORAD score, sleeplessness, and pruritus severity in all children with atopic dermatitis. IL-31 was significantly increased in children with the intrinsic and extrinsic type of atopic dermatitis compared with non-atopic healthy children (p < 0.05-0.001). Further, IL-31 serum levels significantly correlated with SCORAD score (p < 0.01), sleeplessness (p < 0.05), IL-4, and IL-13 levels (p < 0.01) in children with extrinsic atopic dermatitis. There was no correlation of IL-31 with pruritus, total IgE Ab, and ECP levels, whereas ECP levels significantly correlated with the SCORAD score in children with extrinsic atopic dermatitis. Together, IL-31 represents an interesting cytokine especially with regard to the severity of the inflammatory process indicated by the correlation of IL-31 with SCORAD score and Th2 cytokines including IL-4 and IL-13 in children with extrinsic atopic dermatitis.