Thyroid Autoimmunity in Patients with Chronic Urticaria

INTRODUCTION chronic urticaria (CU) is a skin disorder characterized by transient, pruritic wheals persisting for longer than 6 weeks. The etiopathogenesis of the disease is still unclear, but there is evidence that autoimmunity and endocrine dysfunction may be involved. AIM the aim of this study was to determine whether chronic urticaria is statistically associated with thyroid autoimmunity. PATIENTS AND METHODS in a prospective case-control study, we compared the frequency of thyroid auto-antibodies (thyroglobulin antibody, anti-Tg and thyroid peroxidase antibody, anti-TPO) in 70 patients with chronic urticaria and in 70 healthy volunteers. Thyroid auto-antibodies and thyroid hormones (thyroxine (T4), triiodthyronine (T3) and thyroid stimulating hormone (TSH) were measured in all subjects. RESULTS thyroid functional abnormalities were found in 8 (11.43%) patients. Anti-Tg and anti-TPO were positive in 16 (23%) and 21 (30%) patients, respectively. In control group, only one subject (1.42%) had abnormalities in thyroid hormonal status, and two subjects (2.86%) had positive thyroid auto-antibodies. Compared with the control group, the frequency of both anti-Tg and anti-TPO was significantly higher in those with chronic urticaria (P < 0.05). CONCLUSION this study shows a significant association between chronic urticaria and thyroid autoimmunity, and that tests to detect thyroid auto-antibodies are relevant in patients with chronic urticaria.