Goitre

Goitre
Diffuse hyperplasia of the thyroid
Classification and external resources
Specialty	Endocrinology
ICD-10	E01-E05
ICD-9-CM	240.9
DiseasesDB	5332
MedlinePlus	001178
Patient UK	Goitre
MeSH	D006042

A goitre (from the Latin gutteria, struma) is a swelling of the neck or larynx resulting from enlargement of the thyroid gland (thyromegaly), associated with a thyroid gland that is not functioning properly.

Worldwide, over 90.54% cases of goitre are caused by iodine deficiency.

Signs and symptoms

Goitre which is associated with hypothyroidism or hyperthyroidism may be present with symptoms of the underlying disorder. For hyperthyroidism, the most common symptoms are associated with adrenergic stimulation: tachycardia, palpitations, nervousness, tremor, increased blood pressure and heat intolerance. Clinical manifestations are often related to hypermetabolism, including increased metabolism, excessive thyroid hormone, an increase in oxygen consumption, metabolic changes in protein metabolism, immunologic stimulation of diffuse goitre, and ocular changes (exophthalmos). Hypothyroid individuals may have weight gain despite poor appetite, cold intolerance, constipation and lethargy. However, these symptoms are often nonspecific and hard to diagnose.

Morphology

Regarding morphology, goitres may be classified either as the growth pattern or as the size of the growth:

Growth pattern

• Uninodular (struma uninodosa): can be either inactive or a toxic nodule
• Multinodular (struma nodosa): can likewise be inactive or toxic, the latter called toxic multinodular goitre
• Diffuse (struma diffuse): the whole thyroid appearing to be enlarged.

Size

• Class I (palpation struma): in normal posture of the head, it cannot be seen; it is only found by palpation.
• Class II: the struma is palpative and can be easily seen.
• Class III: the struma is very large and is retrosternal; pressure results in compression marks.

• 

  Struma nodosa (Class II)

• 

  Struma with autonomous adenoma

• 

  Struma Class III

Causes

Worldwide, the most common cause for goitre is iodine deficiency, usually seen in countries that do not use iodized salt. Selenium deficiency is also considered a contributing factor. In countries that use iodized salt, Hashimoto's thyroiditis is the most common cause. Goitre can also result from cyanide poisoning; this is particularly common in tropical countries where people eat the cyanide-rich cassava root as the staple food.

Cause	Pathophysiology	Resultant thyroid activity	Growth pattern	Treatment	Incidence and prevalence	Prognosis
Iodine deficiency	Hyperplasia of thyroid to compensate for decreased efficacy	Can cause hypothyroidism	Diffuse	Iodine	Constitutes over 90% cases of goitre worldwide	Increased size of thyroid may be permanent if untreated for around five years
Congenital hypothyroidism	Inborn errors of thyroid hormone synthesis	Hypothyroidism
Goitrogen ingestion
Adverse drug reactions
Hashimoto's thyroiditis	Autoimmune disease in which the thyroid gland is gradually destroyed. Infiltration of lymphocytes.	Hypothyroidism	Diffuse and lobulated	Thyroid hormone replacement	Prevalence: 1 to 1.5 in a 1000	Remission with treatment
Pituitary disease	Hypersecretion of thyroid stimulating hormone, almost always by a pituitary adenoma		Diffuse	Pituitary surgery	Very rare
Graves' disease—also called Basedow syndrome	Autoantibodies (TSHR-Ab) that activate the TSH-receptor (TSHR)	Hyperthyroidism	Diffuse	Antithyroid agents, radioiodine, surgery	1 to 2 cases per 1,000 population per year	Remission with treatment, but still lower quality of life for 14 to 21 years after treatment, with lower mood and lower vitality, regardless of the choice of treatment
Thyroiditis	Acute or chronic inflammation	Can be hyperthyroidism initially, but progress to hypothyroidism
Thyroid cancer			Usually uninodular			Overall relative 5-year survival rate of 85% for females and 74% for males
Benign thyroid neoplasms		Usually hyperthyroidism	Usually uninodular			Mostly harmless
Thyroid hormone insensitivity		Secretional hyperthyroidism, Symptomatic hypothyroidism	Diffuse

• Sarcoidosis
• Amyloidosis
• Hydatidiform mole
• Cysts
• Acromegaly
• Pendred syndrome

Treatment

Goitre is treated according to the cause. If the thyroid gland is producing too much T3 and T4, radioactive iodine is given to the patient to shrink the gland. If goitre is caused by iodine deficiency, small doses of iodide in the form of Lugol's Iodine or KI solution are given. If the goitre is associated with an underactive thyroid, thyroid supplements are used as treatment. In extreme cases, a partial or complete thyroidectomy is required.

Epidemiology

Disability-adjusted life year for iodine deficiency per 100,000 inhabitants in 2002.

  no data

  fewer than 50

  50–100

  100–150

  150–200

  200–250

  250–300

  300–350

  350–400

  400–450

  450–500

  500–800

  more than 800

Goitre is more common among women, but this includes the many types of goitre caused by autoimmune problems, and not only those caused by simple lack of iodine.

History

Goitre and cretinism in Styria, copper engraving, 1815

Women in Miesbacher Tracht, including a goitre choker

Chinese physicians of the Tang Dynasty (618–907) were the first to successfully treat patients with goitre by using the iodine-rich thyroid gland of animals such as sheep and pigs—in raw, pill, or powdered form. This was outlined in Zhen Quan's (d. 643 AD) book, as well as several others. One Chinese book, The Pharmacopoeia of the Heavenly Husbandman, asserted that iodine-rich sargassum was used to treat goitre patients by the 1st century BC, but this book was written much later.

In the 12th century, Zayn al-Din al-Jurjani, a Persian physician, provided the first description of Graves' disease after noting the association of goitre and exophthalmos in his Thesaurus of the Shah of Khwarazm, the major medical dictionary of its time. Al-Jurjani also established an association between goitre and palpitation. The disease was later named after Irish doctor Robert James Graves, who described a case of goitre with exophthalmos in 1835. The German Karl Adolph von Basedow also independently reported the same constellation of symptoms in 1840, while earlier reports of the disease were also published by the Italians Giuseppe Flajani and Antonio Giuseppe Testa, in 1802 and 1810 respectively, and by the English physician Caleb Hillier Parry (a friend of Edward Jenner) in the late 18th century.

Paracelsus (1493–1541) was the first person to propose a relationship between goitre and minerals (particularly lead) in drinking water. Iodine was later discovered by Bernard Courtois in 1811 from seaweed ash.

Goitre was previously common in many areas that were deficient in iodine in the soil. For example, in the English Midlands, the condition was known as Derbyshire Neck. In the United States, goitre was found in the Great Lakes, Midwest, and Intermountain regions. The condition now is practically absent in affluent nations, where table salt is supplemented with iodine. However, it is still prevalent in India, China, Central Asia, and Central Africa.

Goitre had been prevalent in the alpine countries for a long time. Switzerland reduced the condition by introducing iodised salt in 1922. The Bavarian tracht in the Miesbach and Salzburg regions, which appeared in the 19th century, includes a choker, dubbed Kropfband (struma band) which was used to hide either the goitre or the remnants of goitre surgery.

Society and culture

In the 1920s wearing bottles of iodine around the neck was believed to prevent goitre.

Notable cases

• Former US President George H. W. Bush and his wife Barbara Bush were both diagnosed with Graves' disease and goitres, within two years of each other. The disease caused hyperthyroidism and cardiac dysrhythmia. Scientists said that the odds of both George and Barbara Bush having Graves' disease might be 1 in 100,000 or as low as 1 in 3,000,000.
• Andrea True (according to an interview on VH1).

Heraldry

The coat of arms and crest of Die Kröpfner, of Tyrol showed a man "afflicted with a large goitre", an apparent pun on the German for the word ("Kropf").

See also

• David Marine conducted substantial research on the treatment of goitre with iodine.
• Endemic goitre
• Struma ovarii—a kind of teratoma

External links

• National Health Service, UK
• Network for Sustained Elimination of Iodine Deficiency
• Network for Sustained Elimination of Iodine Deficiency—alternate site at Emory University's School of Public Health
• A case and photograph of a huge goitre from Photobucket.com and Doctorkhodadoust.net