Serum levels of anti-thyroid autoantibodies in different thyroid function status

Background
Thyroid disorders are one of the most prevalent medical conditions, especially in women. Autoimmune thyroid diseases are the most common causes in which the patient's immune system attacks thyroid gland with generation of thyroid autoantibodies. However, antibody testing is not widely available for routine clinical practice.
Aim
This study was conducted to determine the level of autoantibodies against thyroid peroxidase (anti-TPO), thyroglobulin (anti-TG), and thyrotropin receptor (TRAB) in different status of thyroid function.
Patients and methods
Thyroid function tests included thyroid-stimulating hormone (TSH), Free T3 (FT3), and Free T4 (FT4) with anti-thyroid autoantibodies (anti-TG, anti-TPO, and TRAB).
Results
Anti-TG level was significantly increased in patients with hypothyroidism when compared with patients with normal thyroid function and control group. Anti-TPO level was significantly increased in patients with hypothyroidism when compared with those with normal thyroid function and control group, and it was significantly increased in patients with hyperthyroidism when compared with patients with normal thyroid function and control group. There was a nonstatistically significant increase in TRAB level in patients with hyperthyroidism when compared with patients with hypothyroidism, those with normal thyroid function, and control group. There was a significant moderate positive correlation between TRAB level and FT3 level and with FT4 level, and in the correlation study between thyroid autoantibodies with each other, there was a significant strong positive correlation between anti-TPO and anti-TG.
Conclusion
Anti-TPO and anti-TG have a role in the pathogenesis and diagnosis of autoimmune thyroid disorders, and their tests should be requested for patients with thyroid dysfunction.