Background: Autoimmune disease has been implicated as a cause of chronic urticaria, and anti-thyroid antibodies have been found in patients with chronic urticaria. Because some patients with chronic urticaria and autoimmune hypothyroidism have had clinical resolution with thyroid hormone replacement, we investigated the effect of thyroid hormone in euthyroid patients with chronic urticaria and thyroid autoimmunity.
Methods: Ten euthyroid patients with refractory hives were treated with thyroxine. Seven patients had elevated anti-thyroid antibodies at baseline. Thyroid function and anti-microsomal and anti-thyroglobulin antibody levels were monitored during treatment. If a clinical response was achieved, thyroxine was discontinued and restarted if symptoms recurred.
Results: Seven patients with elevated anti-thyroid antibodies reported resolution of symptoms within 4 weeks. Three patients without elevated anti-thyroid antibodies did not respond. Five patients had a recurrence of symptoms after treatment was stopped, which resolved after treatment was restarted. Thyroid-stimulating hormone levels decreased in all patients with a clinical response. No correlation between clinical resolution and anti-thyroid antibody levels was seen.
Conclusion: Thyroid autoimmunity in euthyroid patients may be associated with chronic urticaria, and treatment with thyroid suppression can result in clinical remission.