IGHE and autoimmune disease: In recent years, more evidence shows that CSU can be an autoimmune disease as up to 40% of the patients have detectable histamine-releasing immunoglobulin G (IgG) autoantibodies directed against immunoglobulin E (IgE) or the high-affinity IgE receptor on mast cells and basophils or IgE autoantibodies to common structures (e.g., thyroid gland) [2].