A total of 478 patients, mean age 15.5 (3.6-25.3) years, suffering from Turner's syndrome, were studied in order to determine the frequency of autoimmune thyroiditis, which is defined as the presence of antithyroid antibodies (AT-Ab) and typical ultrasound findings. We found 106 (22.2%) patients positive for AT-Ab and of those 49 (10%) also had positive ultrasound findings, and were therefore considered to be affected by thyroiditis. This frequency is significantly higher (p < 0.001) than that seen in the normal population. Goitre was detected on clinical examination in only 16 (33%) and by ultrasound in 19 (39%) patients. Hormonal evaluation showed that 17 patients were euthyroid, 27 had compensated hypothyroidism, 2 were hypothyroid and 3 were in a hyperthyroid phase. Clinical signs or symptoms of hypothyroidism were absent in all hypothyroid patients. In patients with thyroiditis, neither a higher frequency of malformations and autoimmune diseases nor a correlation with karyotype, oestrogens or growth hormone therapy was found.Antithyroid antibodies, thyroiditis, thyroid hormones, thyroid ultrasound, Turner's syndrome

G Radetti, Department of Paediatrics, Regional Hospital of Bolzano, via L Boehler 5, 39100 Bolzano, Italy