ACTA ENDOCRINOLOGICA (BUC)

The aim of this review is to indicate the current position on the role of thyroxine (T4) and fetal brain development with particular relevance to the human situation. Adequate maternal iodine nutrition and maternal circulating thyroxine (T4) concentrations are essential to ensure optimum T4 placental passage which in turn will ensure transport of T4 into fetal brain cells. These processes are discussed and the role of thyroid hormone transporters is considered. The emphasis on isolated maternal hypothyroxinaemia (IH) as an important factor affecting brain development is discussed from the animal experimental point of view as well as in the clinical setting. There is evidence of neurocognitive impairment as assessed by different modalities in children up to the age of 8 years and some suggestion of increased psychiatric disorder in older persons whose mothers had IH during gestation. Although international guidelines have not in general recommended thyroxine therapy for IH the recent demonstration of adverse obstetric outcomes in women with isolated maternal hypothyroxinaemia may warrant a revision of this strategy.

Graves’ orbitopathy usually occurs in thyrotoxic patients at the presentation of the\r\nhyperthyroidism.\r\nAim: we conducted a cross sectional study over 8 and a half years of the relation\r\nbetween Graves’ orbitopathy and thyroid status in patients presenting to our joint thyroidophthalmology\r\nclinic at University Hospital of Wales.\r\nMethods: Patients with active orbitopathy were diagnosed clinically and with\r\nappropriate imaging where necessary. This series excluded patients previously treated with\r\nradioiodine or surgery for Graves’ disease. Of 259 patients 140 (54%) had not had 131I or\r\nsurgical therapy. Thirty four percent of the 140 had never been hyperthyroid of whom 19\r\n(13.5%) were euthyroid. Twenty nine of the 140 (20.7%) were hypothyroid receiving\r\nlevothyroxine at referral. There were no significant differences between the hyperthyroid\r\nand non hyperthyroid groups in the incidence of cigarette smoking, family history of thyroid\r\ndisease or maximum proptosis at presentation.\r\nResults: We found a higher prevalence of smokers than reported in the literature in\r\nmoderate and severe TAO across all thyroid status groups including hypothyroid only\r\npatients. This study has emphasized the occurrence of Graves’ orbitopathy in hypothyroid\r\npatients as well as euthyroid individuals.