Hyperthyroidism radioactive iodine

Antithyroid drugp or thyroid antagonists are used to treat hyperthyroidism. In addition to the antithyroid drugs, hyperthyroidism may be treated by the administration of strong iodine solutions, use of radioactive iodine (131I), or by surgical removal of some or almost all of the tiiyroid gland (subtotal thyroidectomy). 

In the hyperthyroid patient, relieving signs and symptoms and achieving a euthyroid state are the desired outcomes. The method of achieving these outcomes may change over time with the use of antithyroid drugs versus radioactive iodine. 

An elevated 24-hour radioactive iodine uptake (RAIU) indicates true hyperthyroidism the patient s thyroid gland is overproducing T4, T3, or both (normal RAIU 10% to 30%). Conversely, a low RAIU indicates that the excess thyroid hormone is not a consequence of thyroid gland hyperfunction but is likely caused by thyroiditis or hormone ingestion. 

Peptides in Human Urine (Skarzynski and Samecka-Keller), 5, 107 Protein Bound Iodine (Chaney), I, 82 Radioactive Iodine-131 in the Diagnosis of Hyperthyroidism, Blood Plasma Levels of (Silver), 1, 111 Transaminase Activities of Serum and Body Fluids, the Clinical Significance of Alterations in (Wroblew-ski), 1, 314... 

Blood Plasma Levels of Radioactive Iodine-131 in the Diagnosis of Hyperthyroidism Solomon Silver... 

Hyperthyroidism Long-term therapy may lead to disease remission. Also used to ameliorate hyperthyroidism in preparation for subtotal thyroidectomy or radioactive iodine therapy. 

Pretreatment with antithyroid drugs is necessary to avoid the risk of thyroid storm (exacerbation of hyperthyroidism with fever and tachycardia) in the following groups the elderly, people with cardiac disease, and people with severe hyperthyroidism. Antithyroid drugs should be stopped at least 4 days before radioactive iodine is given, and restarted no sooner than 3 days after, to permit uptake of the iodine into the thyroid gland. Antithyroid drugs can usually be stopped after 2-6 weeks as the radioactive iodine takes effect. 

In the adult population, the prevalence of overt hypothyroidism is 19 per 1000 women and 1 per 1000 men with annual incidence of overt hypothyroidism is 4 per 1000 women and 0.6 per 1000 men. Subclinical hypothyroidism is also more common in women, the incidence increases with age, with up to 10% of women older than 60 years having an increased thyroid-stimulating hormone concentration. Subclinical hypothyroidism is more common in people who have been treated for hyperthyroidism with radioactive iodine or surgery, and in those with organ-specific autoimmune diseases, such as pernicious anaemia, type 1 diabetes mellitus, or Addison s disease. 

Kaplan MM, Meier DA, Dworkin HJ. Treatment of hyperthyroidism with radioactive iodine. Endocrinol Metab Clinics North Am 1998 27 205. 

Radioactive iodine is indicated in hyperthyroidism due to Graves disease or toxic nodular goitre and also used as palliative therapy after thyroidectomy for papillary carcinoma of thyroid. 

The three primary methods for controlling hyperthyroidism are antithyroid drug therapy, surgical thyroidectomy, and destruction of the gland with radioactive iodine. 

Therapeutic Techniques. Probably the most prominent therapeutic use of radiopharmaceuticals is radioactive iodine in the treatment of metastatic thyroid cancer. 131I has a half-life of about 8 days and emits gamma and beta rays. When iodine salts are taken into the body, most of the dose is concentrated in the thyroid gland. A dose of radioactive iodine salt similarly concentrates in the thyroid gland. When there is a cancer in the thyroid gland, or the gland is overactive (hyperthyroidism), the excessive... 

The long-term effects of antithyroid drug treatment on the prevalence of ANCAs has been examined in 209 consecutive patients with hyperthyroidism who had been treated with antithyroid drugs, radioactive iodine, thyroidectomy, or a combination of these treatment options... 

Hyperthyroidism treatment involves partial or complete thyroidectomy, radioactive iodine (RAI) treatment, or thioamide therapy. There is no one best approach because treatment is often individualized. 

The thioamides are often used as primary therapy for hyperthyroidism. They are also used as adjunctive therapy to achieve euthyroidism in patients prior to surgery or radioactive iodine therapy. The thioamides primarily inhibit... 

PTH concentrations may be altered in hyperthyroidism, in hypothyroidism, and with lithium carbonate treatment. PTH is decreased and inversely correlated with T3 concentrations in hyperthyroid patients. Serum PTH increases in patients who become hypothyroid after radioactive iodine treatment, and decreases with replacement therapy, changes apparently mediated by serum calcium. Chronic lithium carbonate therapy has been reported to increase parathyroid gland size and circulating intact PTH. ... 

Serial measurement of Tg is most useful in detecting recurrence of DTC following surgical resection or radioactive iodine ablation. Tg determination is used as an adjunct to ultrasound and scanning. Assessment of serum Tg also aids in the management of infants with congenital hypothyroidism, All patients with hyperthyroidism should have elevated Tg low concentrations of Tg may be an indication that thyrotoxicosis factitia is present. 

Hyperthyroidism may be treated with antithyroid drugs such as propylthiouracil (PTU) or methimazole (MMI), radioactive iodine (RAI e.g., I), or surgical removal of the... 

Three common treatment modalities are used in the management of hyperthyroidism surgery, antithyroid medications, and radioactive iodine (RAI) (Table 73-5). The overall therapeutic objectives are to eliminate the excess thyroid hormone and minimize the symptoms and long-term consequences of hyperthyroidism. Therapy must be individuahzed based on the type and severity of hyperthyroidism, patient age and gender, existence of nonthyroidal con-... 

Radioactive iodine ( 1) Cure of hyperthyroidism Most cost effective Permanent hypothyroidism almost inevitable Might worsen ophthalmopathy Pregnancy must be deferred for 6-12 months no breast-feeding Small potential risk of exacerbation of hyperthyroidism Best treatment for toxic nodules and toxic multinodular goiter... 

Franklyn JA, Maisonneuve P, Sheppard MC, et al. Mortality after the treatment of hyperthyroidism with radioactive iodine. N Engl J Med 1998 338 712-718. 

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