Evidence of a new antigen-antibody system (anti-Mic-1) in patients with systemic lupus erythematosus and hyperthyroidism
Salazar-Páramo, M.; García-de la Torre, I.; Hernández-Vazquez, L.; Ortíz-Cadena, A.
Journal of Rheumatology 16(2): 175-180
1989
ISSN/ISBN: 0315-162X PMID: 2746564 Document Number: 329063
Autoimmune thyroid diseases may occur in association with systemic rheumatic disorders, and usually they show a high prevalence of antithyroglobulin and antimicrosomal antibodies. We report 6 patients with the clinical association of systemic lupus erythematosus (SLE) and hyperthyroidism. Of interest, in 5 of the 6 patients (83%), we found an antibody directed against a microsomal extract of human thyroid gland which was different than previous microsomal antibodies in that it was a precipitating antibody; we have called it anti-Mic-1 antibody. We investigated the prevalence of this specific autoimmune reaction in 58 patients with idiopathic SLE, 30 with hyperthyroidism, 15 with Hashimoto's thyroiditis, 25 with insulin dependent diabetes mellitus, 45 with rheumatoid arthritis, and 25 healthy controls. No control had anti-Mic-1 antibody. In addition, this antibody was shown to be organ specific. We suggest that patients with the combined association of SLE and hyperthyroidism may represent a different subset in the spectrum of SLE. The high prevalence of this antigen-antibody reaction in these cases may serve as a serological marker of this association.