Significance of antithyroid antibodies and other auto-antibodies in Saudi patients with chronic urticaria. Possible parameters in predicting chronic over three years disease

Objective

To determine the frequency and significance of thyroid auto-antibodies and antinuclear antibody among Saudi patients with chronic urticaria and to identify markers of chronic urticaria disease.

Materials and methods

Non-interventional, prospective analytical study carried out among consecutive patients with chronic urticaria in the Department of Dermatology, College of Medicine, King Saud University, Riyadh, Saudi Arabia between January 2005 and December 2007. Patients were divided into two groups: Group 1 – with hypothyroidism, Group 2 – without hypothyroidism, both age-matched to normal healthy controls. All patients were investigated for the presence of antithyroglobulin (ATG), antimicrosomal (AMA), antinuclear antibodies (ANA) as well as rheumatoid factor (RF) and antibodies to hepatitis B and C.

Results

A total of 90 participants were included in the study. Significant elevation of anti thyroglobulin antibodies was found in patients with hypothyroidism than in those without hypothyroidism and in the control group (30.4% vs. 24.4% vs. nil, p = 0.022). Elevated titers of antimicrosomal antibodies were seen in chronic urticaria patients with or without hypothyroidism compared to control group. Positive antinuclear antibodies were detected in all groups. There were no significant differences in the severity of the disease in between study groups (p = 0.234). Chronic urticaria was statistically significantly associated with hypothyroidism (p = 0.0014) and with the presence of antithyroglobulin antibodies (p = 0.022). The duration of urticaria was significantly associated with positive antithyroid and anti-nuclear antibodies (p = 0.0315 and p = 0.0056, respectively). Disease severity was not significantly associated with elevations of ANA, TMA and TGA titers (p = 0.558, 0.827 and 0.324, respectively).

Conclusion

Chronic immunologic urticaria may be entertained in patients with long standing urticaria especially in the presence of hypothyroidism and elevated antithyroid antibodies. Assays for thyroid antibodies, TSH and ANA may be justified for early diagnosis of autoimmune urticaria to institute appropriate treatment modalities, hence improve the quality of life.