Graves’ hyperthyroidism

Two cases of fatal fulminant hepatic failure have been described in previously healthy women aged 30 and 32 years who presented with jaundice 4 and 5 months respectively after starting to take propylthiouracil for Graves hyperthyroidism (51). Another case of fatal fulminant liver failure with cholestatic jaundice 2 weeks after the start of treatment with propylthiouracil 100 mg tds has been described (52). 

A 3-year-old child, whose mother had been treated for Graves hyperthyroidism with thiamazole throughout pregnancy, had two scalp lesions and other abnormalities of tissues of ectodermal origin, including dystrophic nails and syndactyly. 

Choanal atresia has been described in an infant whose mother presented in early pregnancy with Graves hyperthyroidism and who took carbimazole in doses up to 60 mg/day in the first trimester (102). She was also clinically and biochemically severely hyperthyroid at this time. 

Tallstedt L, Lundell G, Torring O, Wallin G, Ljunggren JG, Blomgren H, Taube AThe Thyroid Study Group. Occurrence of ophthalmopathy after treatment for Graves hyperthyroidism. N Engl J Med 1992 326(26) 1733-8. 

While this pattern of biochemistry does not exclude transient relapse of Graves hyperthyroidism (despite the finding of negative TSH receptor antibodies), or a transient thyroiditis, the authors speculated that indinavir (prescribed in this patient together with stavudine and lamivudine) had inhibited the glucuronidation of thyroxine and hence caused a rise in serum thyroid hormone concentrations. 

Bogazzi F, Bartalena L, Brogioni S, Scarcello G, Burelli A, Campomori A, Manetti L, Rossi G, Pinchera A, Martino E. Comparison of radioiodine with radioiodine plus lithium in the treatment of Graves hyperthyroidism. J Clin Endocrinol Metab 1999 84(2) 499-503. 

Abraham P, Avenell A, Park CM, et al. A systematic review of drag therapy for Graves hyperthyroidism. 

He CT, Hsieh AT, Pei D, et al. Comparison of single daily dose of methimazole and propylthiouracil in the treatment of Graves hyperthyroidism. Clin Endocrinol. 2004 60 676-681. 

Graves ophthalmopathy develops in more than 80% of cases within 6 months of the diagnosis of Graves hyperthyroidism. Graves ophthalmopathy may occasionally develop before the diagnosis of hyperthyroidism. Thyroid-related orbitopathy is associated with Graves hyperthyroidism in 90% of cases and with autoimmime thyroiditis (Hashimoto s disease) in some 5%. No laboratory evidence of thyroid disease is fiaimd in 5% to 10% of patients. This condition is called ophthalmic or euthyroid Graves ophthalmopathy. 

Results of survey studies among thyroid specialists who treat Graves hyperthyroidism in Europe, Japan, or the United States showed consensus only on the relative lack of a role of thyroidectomy, except for narrow indications. 

Graves hyperthyroidism in the United States is treated in most adults (69%) with whereas the remaining patients receive treatment with the antithyroid drugs PTU or MMI. Conversely, antithyroid drugs are used in Europe (77%) and Japan (88%) in most Graves disease patients, whereas the rest are treated with RAI. 

Holm lA, Manson JF, Michels KB, et al. Smoking and other lifestyle factors and the risk of Graves hyperthyroidism. Arch Intern Med 2005 165 1606-1611. 

What treatment options are available for Graves hyperthyroidism ... 

Case Conclusion HP began methimazole therapy for her Graves hyperthyroidism. She also began propranolol to help control her tachycardia and tremor. During this time HP should avoid excessive exercise or other sympathomimetic drugs until her symptoms of tachycardia have subsided. HP will return to the clinic for follow-up in 4 weeks. At that time, methimazole dose, tolerability, compliance, and thyroid function tests will be reassessed. 

A Methimazole has a longer TV2 than PTU and can be dosed once daily PTU requires three to four daily doses, which may affect compliance. PTU does not cause pretibial myxedema rather Graves hyperthyroidism leads to pretibial myxedema. Methimazole does not interact with amiodarone however, amiodarone can affect thyroid function, leading to both hypo- and hyperthyroidism. PTU therapy may result in spontaneous remission, but patients typically require therapy for many years (1 to 15 years). 

Thyroid disorders. Disturbances in thyroid metabolism can occur at any level of the hypothalams-pituitary-thyroid-peripheral tissue axis. Several of these disorders have been discussed previously. Hyperthyroidism is more prevalent in women than men. The three most common causes of hyperthyroidism are Graves hyperthyroidism, toxic multinodular goiter, and toxic adenoma. The clinical features of hyperthyroidism include hyperkinesis, weight loss, cardiac anomalies (e.g., atrial fibrillation), fatigue, weakness, sweating, palpitations, and nervousness. The typical biochemical laboratory parameters are increased serum free T4 and decreased serum TSH. 

A common approach to Graves hyperthyroidism is to administer a single dose of 5 to 15 mCi(80 to 120 mcCi/g of tissue). ° The optimal method for determining 1 treatment doses for Graves hyperthyroidism is unknown, and techniques have varied from a fixed dose to more elaborate calculations based on gland size, iodine uptake. 

Momotani N, Noh JY, Ishikawa N, Ito K. Effects of propylthiouracil and methimazole on fetal thyroid status in mothers with Graves hyperthyroidism. J Endocrinol Metab 1997 82 3633-3636. 

Mclver B, Rae R Beckett G, et al. Lack of effect of thyroxine in patients with Graves hyperthyroidism who are treated with an antithyroid drug. N Engl 1 Med 1996 334 220-224. 

Leslie WD, Ward L, Salamon EA, et al. A randomized comparison of radioiodine doses in Graves hyperthyroidism [see comment]. J CUn Endocrinol Metab 2003 88 978-983. 

Ljunggren JG, Torring O, Wallin G, et al. Quahty of life aspects and costs in treatment of Graves hyperthyroidism with antithyroid drugs, surgery, or radioiodine Results from a prospective, randomized study. Thyroid 1998 8 653-659. 

Autoimmune thyroiditis (AITD) is one of the most common autoimmune disorders. The humoral immune response is dominant in Graves hyperthyroidism, whereas cellular immune response is more dominant in hypothyroidism caused by chronic AITD (Marcocci and Chiovato, 2000). Thyroid autoantibodies are proteins manufactured by the immune system that are directed against proteins in the thyroid. Although nearly all patients with chronic... 

The most serious and common complication of salt iodization is the development of iodine-induced hyperthyroidism (IIH), which affects mainly older people with nodular goiter another possibifity is the aggravation or even the induction of autoimmune thyroiditis. IIH has been reported in almost all iodine supplementation programs in countries with history of severe ID (Stanbury et ai, 1998). However, IIH can occur following iodine supplementation in areas with previous sufficient iodine intake Galofre et al. (1994) the authors have reported increased incidence of both nodular and Graves hyperthyroidism. Also, increased iodine intake is associated with increased incidence of thyroid autoimmune diseases (Papanastasiou et al, 2000 Zois etai, 2003) (Figure 73.4). 

CIS. Clifton-Bligh, P., Silverstein, G. E., and Burke, G., Unresponsiveness to thyrotropin-releasing hormone (TRH) in treated Graves hyperthyroidism and in euthyroid Graves disease.. Clin. Endocrinol. Metab. 38, 531-538 (1974). 

Ross, D.S., Daniels, G.H., De Stefano, P., Maloof, F., and Ridgway, E.C., Use of adjunctive potassium iodide after radioactive iodine ( ) treatment of Graves hyperthyroidism, J. Clin. Endocrinol. Metab. 57 250 (1983). 

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