[Value of the detection of antithyroid antibodies in thyroid pathology]

Antithyroid microsomal hemagglutination antibody (MCHA) and antithyroglobulin hemagglutination antibody (TGHA) were measured in 629 patients with thyroid disease and 100 controls. Thyroid antibodies were present in 4% of control patients, only in women and at low titer. Thyroid antibodies prevalence was 97% in autoimmune thyroiditis (MCHA: 93%; TGHA: 53%), was 55% in Graves disease before treatment (MCHA: 46%; TGHA: 33%) and 90% in the first year following 131I therapy. Antibodies prevalence was 57% in myxoedema (MCHA: 52%; TGHA: 25%). In patients with iodine overload, antibodies prevalence was 29% in euthyroid patients, 25% in iodine-induced hyperthyroidism and 55% in iodine-induced hypothyroidism. Thyroid antibodies detection should be systematically performed in the routine evaluation of any thyroid disorder. Because of discrepancies between TGHA and MCHA positivity, their simultaneous detection should be performed.