Iodine cretins

Another example of a maternal condition that contributes to birth defects is low circulating iodine. Cretinism is one of the most profound, but completely preventable, syndromes of malformation known. Characteristic consequences of prenatal iodine deficiency include pervasive mental and physical retardation, deaf-mutism (due to primary malformation of the inner ear), lack of muscle tone with a spastic or rigid walk, and failure to attain a height at maturity of more than 1 m. Today, this condition (known as endemic cretinism) is most prevalent in impoverished areas of African and East Asian countries. Prior to implementation of a national program of iodized salt in the early part of the twentieth century, endemic cretinism was commonplace in Switzerland. After institution of iodized salt, deaf-mutism declined 50% within 8 years and no cretins have been born in that country since 1930. 

A number of dietary deficiencies may increase the risk of deleterious cyanide effects. Iodine deficiency is involved in the etiology of such thyroid disorders as goiter and cretinism. These disorders may be exacerbated by excess exposure to cyanide (Delange and Ermans 1971 Ermans et al. 1972). Protein deficiencies and vitamin B12, riboflavin and other vitamins and elemental deficiencies may subject people... 

A deficiency of iodine results iu insufficient synthesis of thyroxine and a low plasma level, so that secretion of TSH is increased in an attempt to stimulate synthesis but this results in enlargement of the thyroid gland (goitre). Iodine deficiency in pregnancy impairs brain development in the foetus, causing mental retardation (known as cretinism). Indeed iodine deficiency is one of the major public health issues worldwide an estimated 200 million people are affected. 

The therapeutic strategy should rely on preventative measures. Endemic goitre and endemic cretinism as well as more subtle deficits of neurological function associated with iodine deficiency have been shown to be prevented with adequate iodine prophylaxis. Adequate and continuous supply is the key to successful prevention programmes. 

Congenital (cretinism) Athyreosis or ectopic thyroid, iodine deficiency TSH receptor-blocking antibodies Absent or present Severe... 

Nonmetallic elements predominating in the ash are phosphorus (700 g in the human body), sulfur (175 g), and chlorine (105 g). Not only are these three elements essential to all living cells but also selenium, fluorine, silicon (Box 4-B), iodine, and boron are needed by higher animals and boron by plants (Fig. 1-17). Iodine deficiency may affect one billion human beings and may cause 20 million cases per year of cretinism, or less severe brain damage.158... 

Iodine must be present in the normal diet to prevent iodine-deficiency goiter or cretinism, and iodine deficiency-related disorders are still a worldwide (although preventable) group of diseases that affect about 150 million people in at least 40 countries. The WHO sponsored a program to control these disorders by the year 2000 (1,2), and since 1990 there has been a remarkable progress in prevention of iodine deficiency disorders. However, by the year 2000 one-third of the population affected by iodine deficiency disorders still did not have access to iodized salt (3). 

Goh KO. Radioiodine treatment during pregnancy chromosomal aberrations and cretinism associated with maternal iodine-131 treatment. J Am Med Womens Assoc 1981 36(8) 262-5. 

There are many forms of hypothyroidism, differing in their cause and age of onset (see Table 31-1). Severe adult hypothyroidism (myxedema) may occur idio-pathically or may be caused by specific factors such as autoimmune lymphocytic destruction (Hashimoto disease). In the child, thyroid function may be congenitally impaired, and cretinism will result if this condition is untreated. Hypothyroidism may result at any age if the dietary intake of iodine is extremely low. Several other forms of hypothyroidism that have a genetic or familial basis also exist.54... 

Iodine Component of the thyroid hormones prevents goiter and cretinism Men women 150 pg/d... 

Or, to put it more positively, by adding small amounts of iodide to common salt we can prevent the medical condition known technically as cretinism, a life-long affliction of innately low intelligence caused by iodine deficiency, and which causes permanent brain damage. Nor does this simple dietary requirement cost very much. To provide all 6.5 billion people on the planet with the 70 micrograms of iodine they need every day would require only 166 tonnes of iodine per year, which represent a mere 2% of the iodine the world produces annually. This is an amount that chemists could easily extract from seaweed, making it a sustainable resource, and indeed this was once the way they obtained this remarkable element. 

In areas where there is also low iodine in the diet a further complication may arise. The thiocyanate that is formed from the cyanide inhibits the uptake of iodine into the thyroid gland. Iodine is used to make hormones that regulate the metabolism of the body, and its deficiency leads to goitre (enlarged thyroid) and cretinism (mental retardation) in the offspring of women with the disorder. 

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