TG and thyroiditis: For example, potential interactions with thyroid autoimmunity and the coagulation pathway may alter mast cell activation.17 There is a high prevalence of thyroid autoantibodies in patients with CAU.18 In our series, all patients had high titers of anti-microsomal antibodies, and one had positive anti-thyroglobulin antibody, a finding consistent with the high prevalence of these thyroid antibodies.