TNF and rheumatoid arthritis: The authors concluded that TNF inhibitors could improve thyroid function in hypothyroid patients with RA (especially in patients who were L-thyroxine-naive and TPOAb+).[30] Furthermore, TNF inhibitors may regulate expression of proinflammatory cytokines and apoptosis in thyroids, leading to reduce level of inflammation, earlier resolution, and decreased fibrosis.[31] Further investigations are still needed to enlighten the effect of TNF inhibitors on thyroid autoimmunity.