AUTOIMMUNE HYPOTHYROIDISM AND HYPERTHYROIDISM IN PATIENTS WITH TURNERS-SYNDROME

A high prevalence of autoimmune thyroid disease (AITD) has been descri bed in Turner's syndrome (TS) but the extent of this association is co ntroversial for the prevalence of thyroid autoantibody and the clinica l impact of thyroid dysfunction. In this study we searched for thyroid disease and thyroid autoantibodies in patients with TS. Seventy-five unselected TS patients (age range 3-30 years) were studied. Sera were tested for thyroid hormones, thyrotropin (TSH), thyroglobulin (TG-ab) and thyroperoxidase (TPO-ab) antibodies. The TSH-receptor antibodies w ith thyroid-stimulating (TS-ab) or TSH-blocking activity (TSHB-ab) wer e measured in the IgG fraction using a bioassay. Ten out of 75 (13.3%) TS patients had AITD: eight had autoimmune thyroiditis (AT) (six with subclinical and two with overt hypothyroidism and one with euthyroidi sm) and one had Graves' disease. The prevalence of AITD increased sign ificantly (p < 0.05) from the first (15%) to the third (30%) decade of life. The prevalence of TPO-ab and/or TG-ab (20%) was higher (p < 0.0 5) in TS than in age-matched female controls and increased From the fi rst (15%) to the third (30%) decade of life. Clinical AITD was diagnos ed in 46% of TS patients with TPO-ab and/or TG-ab. Thyroid-stimulating antibody was detected in the hyperthyroid patient, and TSHB-ab was fo und in one of eight patients with hypothyroid AT. It was concluded tha t: TS patients are at higher than average risk of developing AITD not only in adolescence and adult age but also in childhood; hypothyroidis m, mainly subclinical, is the most frequent thyroid dysfunction; eleva ted TPO-ab and/or TG-ab alone do not imply thyroid dysfunction; TS-ab or TSHB-ab are always associated with thyroid dysfunction although mos t cases of autoimmune hypothyroidism are not due to the latter antibod y.