Treatment of Thyroid Eye Disease in Childhood

As the expectation remains that the expression of GO in children is, in most instances, both mild and transient most of the physicians who are dealing with such cases prefer the 'wait-and-see' policy. Indeed, in our recent study 35 70 of the respondents recommended such a policy for the eye changes. Active intervention (predominantly with steroids) is considered appropriate in case of worsening of eye changes or no improvement of eye changes when the patient has become euthyroid 35 . Doses...

Management

Most patients have corrected themselves by increasing their serum thyroid hormones in the presence of normal TSH 12, 14 . No treatment is necessary in these cases. When the patient presents with hyperthyroid symptoms, especially tachycardia, beta-blockers can be used. The thyroid hormone analogue 3,5,3'-triiodothyroacetic acid (TRIAC) has also been used successfully to treat some symptoms of RTH in children such as increased TSH and goiter 15-18 . This is due to the fact that TRIAC has a higher...

Iodine Deficiency and Supplementation

Iodine deficiency produces a spectrum of disorders - endemic goiter, hypothyroidism, cretinism, and congenital anomalies - that are termed the iodine deficiency disorders. Despite substantial global progress against iodine deficiency, it is estimated that 750 million people worldwide, or approximately 15 of the population, remain iodine deficient and goitrous. In iodine-deficient areas, multiple nutritional and environmental influences contribute to the prevalence and severity of iodine...

Nongenomic Actions Extranuclear Actions

A number of T3 effects occur rapidly and are unaffected by inhibitors of transcription and protein synthesis. The site of these actions has been localized to the plasma membrane, cytoplasm and cellular organelles. The nongenomic actions often have a short latency. Cell culture studies suggest that thyroid hormones rapidly, and nongenomically regulate the Ca2+ ATPase enzyme, the Na+ channel via protein kinase C (PKC), the K+ channel via phosphatidyl-inositol 3 (PI3)-kinase, the Na+ H+ antiporter...

Deiodination of Iodothyronines

Deiodination is the foremost pathway of thyroid hormone metabolism both in quantitative terms but also through activation of T4 by outer ring deiodination to T3, as well as inactivation of both T4 and T3 by inner ring deiodination reviewed in 50 . Three iodothyronine deiodinases (D1-D3) are identified as seleno cysteino-containing membrane proteins with their active enzymatic sites located in the cytoplasma. D1 and D2 convert T4 to T3, while D3 has only inner ring deiodination activity and...

Fetal Maternal Relationships

Pregnancy affects thyroid homeostasis. An increased excretion of iodine in the urine accounts for the increase in thyroid volume even in areas of moderate dietary iodine intake 4 . Some studies, however, do not show an increase in urinary iodine during pregnancy. In either case the increase in thyroid volume is the result of imbalance between the intake and increased requirements of iodine during pregnancy 5 . Iodine deficiency during pregnancy is associated with maternal goitre and reduced...

Optimal Iodine Intake

The recommended daily iodine intake is variable depending the age of the subject (table 1). The recommended intake of iodine in neonates reflects the observed mean iodine intake of young infants exclusively fed human milk in iodine-replete areas 4, 5 . However, it is well established that the iodine content of breast milk is critically influenced by the dietary intake of the pregnant and lactating mother 4, 5 . The iodine intake required in order to achieve a positive iodine balance and to...

Ultrasonography

Because of the superficial location of the thyroid gland, high-resolution real-time gray-scale and color Doppler sonography can demonstrate the normal thyroid anatomy and pathologic conditions with remarkable clarity 58 . With increasing availability, this technique has come to play an ever more important role in the diagnostic evaluation of thyroid diseases. High-frequency transducers (7.5-15.0 MHz) provide both deep ultrasound penetration (up to 5 cm) and a high-definition image, with a...

References

1 Refetoff S Inherited thyroxine-binding globulin (TBG) abnormalities in man. Endocr Rev 1989 10 275-293. 2 Refetoff S Thyroid hormone serum transport proteins Structure, properties and genes and transcriptional regulation. 3 Chan V, Besser GM, Landon J Effects of oestrogen on urinary thyroxine excretion. Br Med J 1972 iv 699-701. 4 Pemberton PA, Stein PE, Pepys MB, Potter JM, Carell RW Hormone binding globulins undergo serpin conformational change in inflammation. Nature 1988 336 257-258. 5...

Thyreoidea

Fig. 10. 99mTc pertechnetate thyroid scan of a hyperfunctioning nodule in the right lobe with complete suppression of uptake in the remainder of the thyroid. disease. Compared with a normal thyroid, the thyroid lobes are slightly larger in all dimensions, and the early and late uptakes are higher. Figure 10 shows an autonomous hyperfunctioning nodule with suppression of extranodular thyroid tissue. If thyrotoxicosis is confirmed biochemically, in addition to elevated levels of TSH receptor...

Monitoring of the Fetus in a Mother with Graves Disease

As neonatal thyrotoxicosis is known to be associated with neurological impairment in some cases there is a requirement to monitor the fetus rather than wait till birth to diagnose thyroid dysfunction. The use of serial in utero ultrasonographic measurements has been shown to accurately measure fetal thyroid size 42 . If the fetal thyroid does not reduce in size in response to antithyroid drug administration then transplacental passage of TsAb causing fetal hyper-thyroidism should be suspected....

Iodine Deficiency

When the aforementioned physiological requirements are not met in a given population, a series of functional and developmental abnormalities occur, including thyroid function abnormalities. Iodine deficiency is now accepted as the most common cause of preventable brain damage in the world. According to the World Health Organization (WHO), iodine deficiency disorders (IDD) affect 740 million people throughout the world, and nearly 50 million people suffer from some degree of IDD-related brain...

Hypothyroidism in Infancy Childhood and Adolescence

Hypothyroidism during childhood and adolescence can result from a variety of congenital or acquired defects (table 2). Table 3. Symptoms of childhood hypothyroidism Growth and developmental delay Short stature Infantilism in anthropometric ratios Bone age delay Motor developmental delay Skin and hair Pale, coarse, dry and cold skin Hypertricosis in forehead and neck Rare, dry, thick hair Myopathy and muscular pseudohypertrophy Sluggish motor performance, sleepiness, cold intolerance Some...

Thyroid Hormone Transport

More than 99 of the circulating thyroid hormone is bound to plasma proteins but can be liberated with great rapidity for entry into cells. The thyroid hormone-binding proteins are comprised of thyroxine-binding globulin (TBG), transthyretin (TTR or thyroxine-binding prealbumin), human serum albumin (HSA) and lipoproteins. Their functions are most probably to ensure a constant supply of TH to the cells and tissues by preventing urinary loss 3 , protect the organism against abrupt changes in...

Diagnostic WorkUp of Congenital Hypothyroidism

A positive newborn screening result calls for immediate diagnostic work-up. Information on maternal medication or morbidity should be obtained to assess the infant's prenatal thyroid status. Clinical examination should be performed to document signs and symptoms of CH and possible associated malformations. There is an increased risk for other congenital anomalies (8.4 ), including cardiovascular, musculoskeletal and CNS malformations 3 . Confirmatory serum measurements of TSH and T4 are...

Pendrins Function in the Thyroid

Parts Fly Rod

The exact mechanism by which pendrin functions in the thyroid is still debated. Based on homology with sulfate transporters, it was initially hypothesized that Fig. 4. Structure of the pendrin protein showing 12 transmembrane domains as proposed by Royaux et al. 18 . Circles show some of the more than 100 different mutations identified in patients with Pendred syndrome and DNFB4. The black circles indicate missense and non-sense mutations whereas the gray circles indicate other mutations types...

Radioactive Iodine

The use of radioactive iodine grew out of collaborative efforts in the 1930s and 1940s of physicists at the Massachusetts Institute of Technology (MIT) and clinicians at the Massachusetts General Hospital (MGH Drs. J. Howard Means, Earle M. Chapman, and others) 3 . The first patient treated with radioactive iodine alone with the intent of curing Graves' disease, was a 55-year-old man who received two doses in 1943 of the very short halflife isotope 130I (t1 2 12 h). Between 1943 and 1945, an...

Info

20-30 rash urticaria arthralgia leukopenia 1 Weetman AP Grave's disease 1835-2002. Horm Res 2003 59(suppl 1) 114-118. 2 Weetman AP Graves' disease. N Engl J Med 2000 343 1236-1248. 3 Chapman EM History of the discovery and early use of radioactive iodine. JAMA 1983 250 2042-2044. 4 Cooper DS Antithyroid drugs. N Engl J Med 2005 352 905-917. 5 Gruneiro-Papendieck L, Chiesa A, Finkielstain G, Heinrich JJ Pediatric Graves' disease outcome and treatment. J Pediatr Endocrinol Metab 2003 16...

C P

Thyroid function tests in patients with Pendred syndrome but with no prior surgery (P, black squares) and unaffected family members (C, black diamonds). The reference rage is shown by light gray shading. The slightly elevated TSH and TG seen in some of the controls may be related to the fact that some are heterozygous for the PDS mutation and that these families live in an area of relatively low iodine intake and high incidence of multinodular goiter. Significant differences were...

Epidemiology

Differentiated thyroid carcinoma (papillary and follicular thyroid carcinoma) is rare during childhood and adolescence. It comprises 90-95 of all pediatric thyroid cancers medullary thyroid carcinoma is present in 5-8 , and undifferentiated anaplastic carcinoma is extremely rare. The annual incidence of differentiated thyroid carcinoma in children below 16 years of age is between 0.02 and 0.3 cases per 100,000, whereas the annual incidence per 100,000 in the general population ranges from 1.2...

Utimobranchial Complex

Heterozygous animals were initially described as having a normal euthyroid phenotype but were later found to have reduced motor coordination skills when compared with wild type mice. Kimura 26 announced in 1996 a mutant mouse lacking Ttf-1. Homozygous animals were stillborn, apparently owing to lack of a normal lung. Mutant mice may contain a rudimentary bronchial tree with severely abnormal epithelium. There is a reduction of the number of cartilage rings of the trachea...

Thyroid Disease in Diabetes Mellitus

The most frequent autoimmune disease in type 1 diabetes affects the thyroid. The etiology of autoimmunity in pancreas and thyroid is a T cell-mediated disease and seems to be due to common genetic susceptibility. Two immune regulatory genes (HLA human leukocyte antigen and CTLA-4 cytotoxic T lymphocyte-associated protein 4) contribute to the susceptibility for both diseases 5, 23 . This locus, also known as the IDDM 12 gene, seems to play a major role in development of autoimmune polyglandular...

Clinical Outcomes of Congenital Hypothyroidism

Longitudinal growth, final height and pubertal development are typically normal in male and female individuals with CH in whom L-T4 therapy is maintained as recommended 15, 16 . Pubertal timing and final height are independent of etiology, severity of CH and the start of L-T4 treatment, but girls with a higher initial dose L-T4 gt 8 xg kg d had an earlier onset of puberty 15 . In contrast to physical signs, the neurodevelopmental outcome of patients with CH largely depends on the early...

Antithyroid Drug Therapy

Medical treatment in the first half of the century consisted of bed rest, quinine, and iodine in the form of Lugol's solution 98 . Partial thyroidectomy was used to provide permanent cures 98 . With the advent of thiouracil and propylthiouracil PTU in the mid-1940s, medical therapy of Graves' improved markedly 99 . Because of the relatively high incidence of toxic reactions that developed following the administration of thiouracil including agranulocyto-sis, leukopenia, and drug fever, PTU...

Thyroid Disease in Turner Syndrome

An association between Turner syndrome TS and thyroid disease was first suggested by Atria et al. 1 in 1948 when they reported post mortem findings of a small thyroid gland with lymphocytic infiltration in a young woman with Turner syndrome. Many authors reported on a higher prevalence of hypothyroidism and an association with positive thyroid antibodies in TS patients table 2 2, 6, 7, 24, 29, 32, 37 . Hypothyroidism is found in up to 35 of TS patients. Thyroid autoimmunity seems to be even...

Iron Deficiency and Supplementation

Worldwide, more than two billion people - mainly children and young women - are iron deficient. In developing countries, 40-50 of school-age children are anemic, approximately 50 because of iron deficiency. Iron and iodine deficiencies often coexist in regions of West and North Africa, 20-30 of school-age children suffer from both goiter and iron-deficiency anemia. Data from animal studies indicate that iron deficiency, with or without anemia, impairs thyroid metabolism. Iron deficiency also...

PET and PETCT

Cancer-seeking radiopharmaceuticals have been evaluated for more than a decade to improve differentiation between benign and malignant thyroid nodules. Positron emission tomography with fluorine 18-fluorodeoxyglucose FDG is well established as a functional imaging tool for diagnostic oncologic imaging. It yields metabolic information about lesions that is not provided with conventional morphologic imaging modalities such as US, CT and MRI 44 . Studies using FDG PET for tumor staging and...