Characterising inflammatory markers in two childhood autoimmune diseases (JIA and JDM) pre and post methotrexate

Background Methotrexate (MTX) is the first line of therapy for patients with juvenile idiopathic arthritis (JIA) and juvenile dermatomyositis (JDM). The mechanisms of action of MTX in childhood autoimmunity are not fully elucidated. The primary target sites of inflammation of JIA and JDM i.e. joint and muscle, respectively do not represent sites from which samples can be easily obtained to monitor inflammatory markers. In contrast peripheral blood is accessible and can be obtained at time of routine clinical screen. We hypothesized that changes in peripheral blood of patients would be informative in monitoring disease and understanding inflammatory pathways that are modulated by MTX.