Autoimmune thyroid disease and chronic urticaria.

We report six cases of autoimmune thyroid disease associated with chronic urticaria and briefly review the literature, including the histopathological nature of such lesions, and their aetiology and pathogenesis. In view of the prevalence of thyroid disease in patients with chronic urticaria, screening measurements of thyrotropin and anti-thyroperoxidase antibodies are recommended, although negative antibodies do not exclude a relationship between urticaria and thyroid autoimmunity. After failure of conventional therapy for urticaria, patients who are apparently clinically euthyroid may be considered for a trial with levothyroxine. Improvement of urticaria was seen with levothyroxine treatment in three of four patients with only marginal abnormalities in thyroid function.