Incidence of thyroid hormone autoantibodies in patients with thyroid diseases with respect to diagnosis, other types of autoantibodies, duration of disease and treatment.

Thyroid hormone autoantibodies (THAA] were estimated in a total of 149 patients (139 women and 10 men) with various thyroid diseases. THAA were found in a total of 22 patients (all women), i.e. 14.7%. In 8 of them both T4Ab and T3Ab were found, while T4Ab only were found in 4 patients and T3Ab only in 10 patients. The highest incidence of THAA was found in patients with diffuse lymphocytic thyroiditis (i.e. 11 cases out of a total of 64 patients) and similarly high incidence was in patients with suspected autoimmune goiter but without thin needle biopsy (i.e. 5 cases out of a total of 21 patients). If only the patients with manifested or silent hypothyroidism were selected, T4Ab were found exclusively in this group, while the incidence of T3Ab was 3 times higher as that in patients without hypothyroidism. Though the incidence of T4Ab in patients with positive antithyroglobulin and antimicrosomal antibodies was 3 times higher than in negative ones, the difference was not significant. No correlation was found between the incidence of THAA on one hand and the duration of disease, the duration of treatment and the drug used for treatment on the other. However, a significant correlation was found between the incidence of THAA and the presence of goiter (P less than 0.05).