[Thyroid autoantibodies in diabetes mellitus and rheumatoid arthritis]

In 58 patients with rheumatoid arthritis and 101 patients with diabetes mellitus (type I) microsomal antibodies of the thyroid gland as well as antinuclear factors were determined and their frequency was compared with the frequency in test persons with hyperthyroidism, bland struma and a control group. Only in diabetes mellitus with 13% an increased presence of humoral sensitization of the thyroid gland was found, whereas relevant to this no considerable differences were present between rheumatoid arthritis (5%), bland struma (5%) and controls (4%). As we expected the frequency of antibodies was high with 74% in the diffuse hyperthyroidism. In patients with rheumatism antinuclear factors were increasedly found only in higher degrees of titres. Though the determination of microsomal autoantibodies is only one parameter in the immunological diagnosis of the thyroid gland, it seems that according to our investigations a Hashimoto-thyroidism in rheumatoid arthritis does not increasedly occur. Overlapping immune reactions were found only among presumable autoimmunoendocrinopathies. The thesis of the preferred combination of autoimmune sensitization among the groups with organ-specific or organ-unspecific antigens is supported according to the present findings. The insignificant appearance of thyroid autoantibodies in the bland struma refers to the fact that in the endemic area immunomechanisms play an inferior role for the development of struma.