Deaf mutism

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. 

Iodine Hypothyroid goiter, neuromuscular impairment, deaf-mutism, increased embryonic and postnatal mortality, cognitive impairment, impaired fertility, cretinism (severe cases) Thyrotoxicosis nodular goiter, weight loss, tachycardia, muscle weakness, warm skin Decreased long-term inadequate intake... 

Fetus abortion, stillbirth, congenital anomalies, increased perinatal mortality, increased infant mortality, neurological cretinism (mental deficiency, deaf mutism, spastic deplegia, squint), hypothyroid cretinism (mental deficiency), psychomotor defects. 

Fetus Abortions Stillbirths Congenital anomalies Increased perinatal mortality Endemic cretinism Deaf mutism... 

In 1971, maternal hypothyroidism seemed an unlikely cause, as no such syndrome as cretinism had been noted in children born to hypothyroid mothers infants suffering from congenital hypothyroidism do not show the features of deaf mutism or neuromuscular defect as seen in the common form of cretinism. This made elemental iodine deficiency an attractive hypothesis (Pharoah et aL, 1971). 

Mentai deficiency, deaf mutism, spastic dipiegia, squint Hypothyroid cretinism ... 

The most severe effect is endemic cretinism, which is characterized by mental defect, deaf mutism and spastic diplegia. 

Deaf mutism Usually present Absent (deafness, mental retardation. early in pregnancy (before... 

Reduction in Mentai deficiency Deaf-mutism Hypothyroidism... 

The effects of iodine deficiency are increased social and economic costs on individuals and communities. The costs arise from the obvious disabilities of mental deficiency and deaf mutism. Economic implications of those effects are reduced work output in the household and in the labor market, and the costs of medical and institutional care. A more critical effect on mental status is poor school performance by children, resulting in long-term effects throughout the life span (Table 79.6). 

Notes The important consequences of iodine deficiency in fhe affecfed human popuiafion are menfai deficiency, deaf mutism and hypothyroidism, which increase the economic cost of treatment and reduce the individuai/community work output/productivity. iodine intervention in such communities reduced such adverse heaith effects which, in turn, increased work output both at the individuai and at the community ievei, reduced the cost of medicai assessment and treatment, and reduced educationai costs. 

In Minas Gerais, for example, a study showed an endemic mean goiter rate of 44% and identified cretinism, deaf-mutism, and mental retardation in the most affected areas. In Sao Paulo, between 1940 and 1947, 22000 preschool children and adolescents were assessed, and the occurrence of goiter varied from 5 to 10% in the coastal... 

It has not been possible yet to reproduce in animals the full clinical syndrome of cretinism - with deaf mutism and spastic diplegia - although only limited observations have been made into the postnatal period. 

We have examined 69 cretins from the Province of Qinghai in the Peoples Republic of China, an endemia where both myxoedematous and neurological cretinism occur. A characteristic neurological syndrome was observed in both euthyroid and hypothyroid individuals. The neurological findings were similar to those which have previously been reported intellectual impairment, deaf-mutism, pyramidal... 

Italy,Sardinia,England,in the United Provinces of India and in Argentina.However, Wespi had shown a correlation between the decline of deaf-mutism and the extent of salt iodination which was introduced independently in several Swiss cantons.This correlation was only time related and other factors could equally have been responsible. Wespi s analysis was subsequently disputed on the ground that no cretins were born about the time the iodine prophylaxis was introduced, indeed, all the cretins were born at least 10 years previously. 

Nervous type deaf mutism, spastic diplegia mental retardation and strabismus... 

When dealing with starvation, individual nutritional factors tend not to be assessed. Yet lack of specific micronutrients could very well affect cognition. Certainly, dietary iodine deficiency is implicated in endemic cretinism with marked, often irreversible, mental retardation, deaf-mutism, and motor defects. While endemic goiter afflicts 200 million people worldwide, only in regions of severe deficiency are infants born cretinous. 

Abortions Stillbirths Congenital Anomalies Increased Perinatal mortality Increased Infant mortality Neurological cretinism -(Mental deficiency deaf mutism spastic diplegia squint)... 

Another major effect of fetal iodine deficiency is the condition of endemic cretinism. This condition, which occurs with an iodine intake of below 25 ug per day in contrast to a normal intake of 100-150 ug per day, is still widely prevalent, affecting for example up to 10 per cent of the populations living in severely iodine deficient areas in India, Indonesia and China. In its most common form, it is characterised by mental deficiency, deaf mutism and spastic diplegia, which is referred to as the "nervous" or neurological type in contrast to the less common "myxedematous" type characterised by hypothyroidism with dwarfism. 

Apart from its prevalence in Asia and Oceania cretinism also occurs in Africa and in South America in the Andean region (Ecuador, Peru, Bolivia). In all these situations, with the exception of Zaire, neurological features are predominant. In Zaire the myxedematous form is more common, probably due to the high intake of cassava. However there is considerable variation in the clinical manifestations of neurological cretinism which include isolated deaf mutism and mental defect of varying degrees. 

Mass prophylaxis of goiter with iodized salt was first introduced in Switzerland and in Michigan in the United States. In Switzerland, the widespread occurrence of a severe form of mental deficiency and deaf mutism (endemic cretinism) was a heavy charge on public funds. However, following the introduction of iodized salt, goiter incidence declined rapidly and cretins were no longer born. Goiter also disappeared from army recruits. 

Congenital anomalies Neurological cretinism Mental deficiency, deaf mutism, spastic diplegia, squint Hypothyroid cretinism Mental deficiency, dwarfism, hypothyroidism Psychomotor defects Increased perinatal mortality Neonatal hypothyroidism Retarded mental and physical development Increased infant mortality Retarded mental and physical development... 

Endemic Occurrence of a disease confined to a community Endemic Cretinism A state resulting from the loss of function of the maternal thyroid gland due to iodine deficiency during pregnancy characterised by mental defect, deaf-mutism and spastic paralysis in its fully developed form... 

The most severe effect of iodine deficiency is cretinism, which is rare in areas of mildly endemic deficiency but may have reached 5-10% or more in areas with severe deficiency. There are general classifications of cretinism, the symptoms of which frequently overlap. Neurological cretinism presents as extreme mental retardation, deaf-mutism, and impaired motor function including spastic gait. 

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