Graves' disease

[1] Signs and symptoms of hyperthyroidism may include irritability, muscle weakness, sleeping problems, a fast heartbeat, poor tolerance of heat, diarrhea and unintentional weight loss.

[1] Other symptoms may include thickening of the skin on the shins, known as pretibial myxedema, and eye bulging, a condition caused by Graves' ophthalmopathy.

[1] The disorder results from an antibody, called thyroid-stimulating immunoglobulin (TSI), that has a similar effect to thyroid stimulating hormone (TSH).

[1][4] Typically, blood tests show a raised T3 and T4, low TSH, increased radioiodine uptake in all areas of the thyroid, and TSI antibodies.

Symptoms of the resultant hyperthyroidism are mainly insomnia, hand tremor, hyperactivity, hair loss, excessive sweating, oligomenorrhea, itching, heat intolerance, weight loss despite increased appetite, diarrhea, frequent defecation, palpitations, periodic partial muscle weakness or paralysis in those especially of Asian descent,[7] and skin warmth and moistness.

[8] Further signs that may be seen on physical examination are most commonly a diffusely enlarged (usually symmetric), nontender thyroid, lid lag, excessive lacrimation due to Graves' ophthalmopathy, arrhythmias of the heart, such as sinus tachycardia, atrial fibrillation, and premature ventricular contractions, and hypertension.

[3] While a theoretical mechanism occurs by which exposure to severe stressors and high levels of subsequent distress such as post-traumatic stress disorder could increase the risk of immune disease and cause an aggravation of the autoimmune response that leads to Graves disease, more robust clinical data are needed for a firm conclusion.

[citation needed] Genes believed to be involved include those for thyroglobulin, thyrotropin receptor, protein tyrosine phosphatase nonreceptor type 22 (PTPN22), and cytotoxic T-lymphocyte–associated antigen 4, among others.

[13] The bacterium Yersinia enterocolitica bears structural similarity with the human thyrotropin receptor[11] and was hypothesized to contribute to the development of thyroid autoimmunity arising for other reasons in genetically susceptible individuals.

Thyroxine receptors in the pituitary gland are activated by the surplus hormone, suppressing additional release of TSH in a negative feedback loop.

[citation needed] Graves' disease is an autoimmune disorder, in which the body produces antibodies that are specific to a self-protein - the receptor for thyroid-stimulating hormone.

The infiltrative exophthalmos frequently encountered has been explained by postulating that the thyroid gland and the extraocular muscles share a common antigen, which is recognized by the antibodies.

The three types of autoantibodies to the TSH receptor are: Another effect of hyperthyroidism is bone loss from osteoporosis, caused by an increased excretion of calcium and phosphorus in the urine and stool.

Serologically detected thyroid-stimulating antibodies, radioactive iodine uptake, or thyroid ultrasound with Doppler all can independently confirm a diagnosis of Graves disease.

[19] Differentiating common forms of hyperthyroidism such as Graves' disease, single thyroid adenoma, and toxic multinodular goiter is important to determine proper treatment.

[22][23][24] Other distinctive features of TAO include lid retraction, restrictive myopathy, superior limbic keratoconjunctivitis, and exposure keratopathy.

[26] Treatment of Graves disease includes antithyroid drugs that reduce the production of thyroid hormone, radioiodine (radioactive iodine I-131) and thyroidectomy (surgical excision of the gland).

The risk of recurrence is about 40–50%, and lifelong treatment with antithyroid drugs carries some side effects such as agranulocytosis and liver disease.

Therapy with radioiodine is the most common treatment in the United States, while antithyroid drugs and/or thyroidectomy are used more often in Europe, Japan, and most of the rest of the world.

β-Blockers (such as propranolol) may be used to inhibit the sympathetic nervous system symptoms of tachycardia and nausea until antithyroid treatments start to take effect.

[32] Disadvantages of this treatment are a high incidence of hypothyroidism (up to 80%) requiring eventual thyroid hormone supplementation in the form of a daily pill(s).

Its risks are injury of the recurrent laryngeal nerve, hypoparathyroidism (due to removal of the parathyroid glands), hematoma (which can be life-threatening if it compresses the trachea), relapse following medical treatment, infections (less common), and scarring.

Radioiodine uptake study may be done after surgery, to ensure all remaining (potentially cancerous) thyroid cells (i.e., near the nerves to the vocal cords) are destroyed.

A 2013 review article concludes that surgery appears to be the most successful in the management of Graves' disease, with total thyroidectomy being the preferred surgical option.

Severe cases threatening vision (corneal exposure or optic nerve compression) are treated with steroids or orbital decompression.

Studies have consistently shown that pulse intravenous methylprednisolone is superior to oral glucocorticoids both in terms of efficacy and decreased side effects for managing Graves' orbitopathy.

If the eyes are proptotic (bulging) enough that the lids do not close completely at night, dryness will occur – with the risk of a secondary corneal infection, which could lead to blindness.

[49] Prior to these, Caleb Hillier Parry,[50] a notable provincial physician in England of the late 18th century (and a friend of Edward Miller-Gallus),[51] described a case in 1786.

[52] However, fair credit for the first description of Graves disease goes to the 12th-century Persian physician Sayyid Ismail al-Jurjani,[53] who noted the association of goiter and exophthalmos in his Thesaurus of the Shah of Khwarazm, the major medical dictionary of its time.

[44][54] Agents that act as antagonists at thyroid stimulating hormone receptors are under investigation as a possible treatment for Graves' disease.

Graves disease symptoms
Histopathology of a case of Grave's disease. It shows marked hyperplasia of thyroid follicular cells , generally more so than toxic multinodular goitre , forming papillae into the thyroid follicles, and with scalloping of the peripheral colloid.
Scan of affected thyroid before ( top ) and after ( bottom ) radioiodine therapy
Most common causes of hyperthyroidism by age [ 38 ]
Marty Feldman used his bulging eyes, caused by Graves' disease, for comedic effect.