Three treatment modalities are available for Graves' disease: antithyroid drugs, surgery and radioactive iodine (RAI). None has been shown to be ideal or superior to the others. There are wide differences between individual physicians and between the physicians in different countries on the optional treatment for childhood hyperthyroidism. While antithyroid drugs remain the initial treatment of choice in almost all the medical centers in Europe, with surgery being used mainly to deal with antithyroid failures, radioiodine is preferred by only a small percentage of physicians for this group of patients. In the USA, on the contrary, radioiodine treatment of thyrotoxicosis in children has strong advocates, who emphasize the safety, simplicity and economic advantages of iodine-131 ablation, which should be considered more commonly in children. Until now, the available data have shown no significant increase in thyroid neoplasia, gonadal injury or congenital abnormalities in the offspring of older children and adults receiving RAI for thyrotoxicosis. Given the considerable increase in the risk of thyroid cancer in young children exposed to external radiation, it has been hypothesized that there may be a small increase in the risk of thyroid cancer in young children treated with RAI. Until long-term data on safety are available, specifically for young children, differences between the physicians in different countries will remain.
GE Krassas and GJ Kahaly
Until recently there was no imaging technique available which could demonstrate pathological changes in orbital tissues and could be regarded as a reliable measure of inflammation in thyroid eye disease (TED). Pentetreotide (a synthetic derivative of somatostatin) labelled with 111In has been used to localize tumours which possess surface or membrane receptors for somatostatin in vivo using a gamma camera (1). This technique visualizes somatostatin receptors in endocrine-related tumours in vivo and predicts the inhibitory effect of the somatostatin analogue octreotide on hormone secretion by the tumours (1). By applying 111In-DTPA-d-Phe octreotide scintigraphy (octreoscan), accumulation of the radionuclide was also detected in both the thyroid and orbit of patients with Graves' disease (2-4). If peak activity in the orbit 5h after injection of radiolabelled octreotide is set at 100%, a decrease to 40+/-4% is found at 24h, significantly different from the decrease in blood pool radioactivity, which is 15+/-4% at 24h. Accumulation of the radionuclide is most probably due to the presence in the orbital tissue of activated lymphocytes bearing somatostatin receptors (5). Alternative explanations are binding to receptors on other cell types (e.g. myoblasts, fibroblasts or endothelial cells) or local blood pooling due to venous stasis by the autoimmune orbital inflammation.
GE Krassas and Z Laron
Graves' disease (GD) is the most common cause of juvenile thyrotoxicosis in children and adolescents (1, 2). Three treatment modalities are now available for the treatment of Graves' thyrotoxicosis in childhood: antithyroid drugs (ATD), surgery and radioactive iodine (RAI). However, none of these treatments has been shown to be ideal or clearly superior to the others. Physicians in different countries have different approaches concerning the optimal treatment of juvenile GD.In a European questionnaire study (3), which was conducted by the European Thyroid Association in 1993 and in which 99 individuals or groups from 22 countries participated, it was found that 22 out of 99 physicians from nine countries would consider RAI treatment as the treatment of choice for children with recurrent thyrotoxicosis after surgery, or with recurrent thyrotoxicosis 2 years after ATD. However, RAI is preferred by only a small percentage of physicians for this group of patients in Europe. Hardly any of the respondents chose RAI for the patients with a toxic adenoma or a multinodular toxic goiter (3). On the other hand, in view of the difficulties with medical therapy in children and adolescents, including poor compliance, a high rate of relapse, drug toxicity and continued thyroid enlargement, some eminent American physicians emphasize the safety, simplicity and economic advantages of (131)I ablation which should be considered more commonly in children (4, 5).We had the opportunity to conduct a similar study during a pediatric thyroidology symposium, which was organized by Professors Buyugkebiz and Laron in Izmir (Smyrna) Turkey from 30 October to 1 November 2003. During the congress a questionnaire with the following four questions was circulated among the 120 participants from eight countries who were mainly paediatric endocrinologists. Most of them were from Turkey and the rest, except for one who came from the USA, were Europeans. Sixty-one out of the 120 physicians responded.
GE Krassas and AE Heufelder
Thyroid eye disease (TED) is a debilitating disease impairing the quality of life of affected patients. Treatment is often not satisfactory. This review summarizes the existing literature and discusses the most widely used forms of treatment for TED such as glucocorticoids (GCs), and other immunosuppressive agents. GCs are the most commonly used treatment in patients with TED. Other immunosuppressive agents such as cyclosporin A, azathioprin, cyclophosphamide and ciamexone have been used, but the results are modest at best and indicate an unfavorable benefit-risk relationship. Limited experience indicates that methotrexate may be effective even in patients with refractory TED. Somatostatin analogs, octreotide and lanreotide, may provide a valuable, although costly, therapeutic alternative to GCs. Orbital radiotherapy has been used in the management of TED for almost 60 years. However, its beneficial effects have been questioned recently by several studies, the details of which have not yet been published. Other studies have argued in favor of orbital radiotherapy; however, the benefits appear to be limited to improvement of extraocular muscle dysfunction.
GE Krassas, TT Kaltsas, N Pontikides, H Jacobs, W Blum and I Messinis
Leptin, a product of the ob gene, is a 16 kDa protein which is produced by adipocytes. In humans, obesity is a common finding in women with polycystic ovary syndrome (PCOS). The role, however, of leptin in PCOS is not clear. Some studies have reported increased levels of leptin in PCOS, while others report that they are normal. Also, insulin resistance is a common finding in PCOS. The aim of this study was to investigate further the role of insulin in leptin secretion in patients with PCOS by treating them for 10 days with diazoxide, an insulin-reducing compound. Eight women with PCOS, mean age 22.1 +/- 2.7 years, with mean body mass index (BMI) 28.4 +/- 5.7kg/m2, were studied. An oral glucose tolerance test (OGTT) was performed in all women and blood samples were taken before and at 30, 60, 90, 120 and 150 min after the administration of glucose. Glucose, insulin, leptin, free testosterone, delta4 androstenedione, sex hormone binding globulin (SHBG), LH, FSH, IGF-I and insulin-like growth factor-binding protein-3 (IGFBP-3) were measured in the sera taken before the administration of glucose, while glucose and insulin levels were measured in all samples which were collected after the administration of glucose. Diazoxide 300 mg daily was given to all women starting after the end of the OGTT for 10 days. A second OGTT was performed the day after the discontinuation of the diazoxide treatment. The same hormonal and biochemical parameters were also measured in all patients during the second OGTT. After the administration of diazoxide a reduction in sum insulin (262 +/- 147 vs 679 +/- 341 microU/ml. P<().01), leptin (18.5 +/- 10.6 vs 24.2 +/- 10.2 ng/ml, P<0.01), free testosterone (3.0 +/- 1.9 vs 5.1 +/- 1.9 pg/ml, P<0.01), delta4 androstenedione (3.8 +/- 1.9 vs 5.7 +/- 2.0 ng/ml, P<0.01) and IGF-I (219.5 +/- 69.2 vs 314.5 +/- 82.3 ng/ml, P<0.01) levels was observed. Serum SHBG (38.8 +/- 16.8 vs 27.8 +/- 12.1 nmol/l, P<0.01) and sum glucose levels (994.1 +/- 252.7 vs 711.1 +/- 166.1 mg/dl, P<0.05) were increased while IGFBP-3 (3.96 +/- 2.49 vs 3.75 +/- 2.24mg/l), FSH (6.2 +/- 1.8 vs 6.0 +/- 2.5 mU/l) and LH (18.9 +/- 6.7 vs 21.4 +/- 6.7 mU/l) concentrations did not change significantly. A significant positive correlation was found between serum leptin and BMI values before and after administration of diazoxide as well as between leptin, insulin and IGFBP-3 values. Also, sum insulin values correlated significantly with BMI. However, when multiple regression analysis was used this correlation was eliminated except that between leptin and BMI. This was most probably due to the small number of cases. The mechanism of the reduction of leptin levels is unclear. However, it is suggested that the concomitant decrease of insulin levels may play a role.
MF Prummel, A Bakker, WM Wiersinga, L Baldeschi, MP Mourits, P Kendall-Taylor, P Perros, C Neoh, AJ Dickinson, JH Lazarus, CM Lane, AE Heufelder, GJ Kahaly, S Pitz, J Orgiazzi, A Hullo, A Pinchera, C Marcocci, MS Sartini, R Rocchi, M Nardi, GE Krassas and A Halkias
To improve management of patients with Graves' orbitopathy, a multi-center collaborative approach is necessary in order to have large enough sample sizes for meaningful randomized clinical trials. This is hampered by a lack of consensus on how to investigate the eye condition. The European Group on Graves' Orbitopathy aims to overcome this and has designed a preliminary case record form (CRF) to assess Graves' orbitopathy patients. This form was used in this first multi-center study. AIM: To investigate patient characteristics and treatment strategies in 152 new consecutively referred patients with thyroid eye disease seen in nine large European referral centers. METHODS: Newly referred patients with Graves' orbitopathy were included who were seen between September and December 2000. Demographic data and a complete ophthalmological assessment were recorded. RESULTS: One-hundred and fifty-two patients (77% females) were included. Diabetes was present in 9%, and glaucoma or cataract in 14% of patients. Forty percent were current smokers, 9% also had dermopathy, and only 33% reported a positive family history of thyroid disease. Mild eye disease was seen in 40%, moderately severe eye disease was seen in 33% and severe eye disease was seen in 28% of patients. Soft tissue involvement was the most frequent abnormality (seen in 75%), proptosis > or =21 mm was found in 63%, eye motility dysfunction in 49%, keratopathy in 16% and optic nerve involvement was found in 21% of patients. According to the clinical impression, 60% had active eye disease. Immunosuppressive treatment was planned more frequently in active patients (57/86; 66%) than in inactive patients (5/57, 9%; Chi-square 46.16; P<0.02). There were no important differences among the eight centers regarding the severity and the activity of their patients. CONCLUSIONS: In view of the large number of patients recruited in only 4 months, multi-center studies in the eight EUGOGO centers appear to be feasible.