Thyroid autoantibodies in patients with systemic lupus erythematosus

Autoimmune thyroid disease has been described in patients with systemic lupus erythematosus (SLE). Presence of autoantibodies specific to thyroid antigens are indicative of autoimmune thyroid disease. The aim of this study was to determine whether anti-thyroid peroxidase (anti-TPO Abs) and anti-thyroglobulin antibodies (anti-Tg Abs) were present in SLE patients compared to healthy blood donors, as well as to examine the thyroid function in the same subjects. We discovered that 12 patients had anti-TPO Abs, 6 had anti-Tg Abs while five had both. In control group we detected two subjects with anti-TPO Abs and one with anti-Tg Abs. From 12 patients with anti-TPO Abs, 6 were hypothyroid, two hyperthyroid and four were euthyroid. From 6 patients with anti-Tg Abs, four were hypothyroid, one was hyperthyroid and one was euthyroid. All patients with both types of autoantibodies had abnormal thyroid function, four were hypothyroid and one was hyperthyroid. Statistically significant difference was found in the frequency of anti-thyroid autoantibody present in SLE patients compared to control group. Some of those patients had subclinical or clinical thyroid dysfunction. In the patients prevalence of hypothyroidism was greater than hyperthyroidism.