Cretinism is a condition of severely stunted physical and mental growth due to untreated congenital

Congenital disorder

A congenital disorder, or congenital disease, is a condition existing at birth and often before birth, or that develops during the first month of life , regardless of causation...

 deficiency of thyroid

Thyroid

The thyroid gland or simply, the thyroid , in vertebrate anatomy, is one of the largest endocrine glands. The thyroid gland is found in the neck, below the thyroid cartilage...

 hormone

Hormone

A hormone is a chemical released by a cell or a gland in one part of the body that sends out messages that affect cells in other parts of the organism. Only a small amount of hormone is required to alter cell metabolism. In essence, it is a chemical messenger that transports a signal from one...

s (congenital hypothyroidism

Congenital hypothyroidism

Congenital hypothyroidism is a condition of thyroid hormone deficiency present at birth. Approximately 1 in 4000 newborn infants has a severe deficiency of thyroid function, while even more have mild or partial degrees. If untreated for several months after birth, severe congenital hypothyroidism...

) usually due to maternal hypothyroidism

Hypothyroidism

Hypothyroidism is a condition in which the thyroid gland does not make enough thyroid hormone.Iodine deficiency is the most common cause of hypothyroidism worldwide but it can be caused by other causes such as several conditions of the thyroid gland or, less commonly, the pituitary gland or...

.

Etymology and use of cretin

The disused term cretin was a medical term which described a person so affected with the condition, but, as with words such as spastic

Spastic

The word spastic is used differently depending on location which has led to some controversy and misunderstanding. Derived via Latin from the Greek spastikos , the word originally referred to a change in muscles affected by the medical condition spasticity, which is seen in spastic diplegia and...

and lunatic

Lunatic

"Lunatic" is a commonly used term for a person who is mentally ill, dangerous, foolish, unpredictable; a condition once called lunacy. The word derives from lunaticus meaning "of the moon" or "moonstruck".-Lunar hypothesis:...

, it can also have a vulgar connotation and can be used disparagingly. Cretin became a medical term in the 18th century, from an Alpine

Alps

The Alps is one of the great mountain range systems of Europe, stretching from Austria and Slovenia in the east through Italy, Switzerland, Liechtenstein and Germany to France in the west....

 French

French language

French is a Romance language spoken as a first language in France, the Romandy region in Switzerland, Wallonia and Brussels in Belgium, Monaco, the regions of Quebec and Acadia in Canada, and by various communities elsewhere. Second-language speakers of French are distributed throughout many parts...

 dialect; it saw wide medical use in the 19th and early 20th centuries, and then spread more widely in popular English as a markedly derogatory term for a person who behaves stupidly. Because of its pejorative connotations in popular speech, health-care workers have mostly abandoned cretin.

Other speculative etymologies have been offered:

• From creta, Latin for chalk, because of the pallor
  Pallor
  Pallor is a reduced amount of oxyhaemoglobin in skin or mucous membrane, a pale color which can be caused by illness, emotional shock or stress, stimulant use, lack of exposure to sunlight, anaemia or genetics....
  
   of those affected.
• From "Crete", where iodine insufficiency (hypothyroidism) was common prior to the modern era.
• From cretira, Grisson-Romance creature, from Latin creatus.
• From cretine, French for alluvium (soil deposited by flowing water), an allusion to the affliction's suspected origin in inadequate soil.
• From "chretien," French for "Christian" or "Christlike," because those affected were so mentally handicapped that they were considered incapable of sinning

Sporadic cretinism due to congenital hypothyroidism

Congenital hypothyroidism

Congenital hypothyroidism

Congenital hypothyroidism is a condition of thyroid hormone deficiency present at birth. Approximately 1 in 4000 newborn infants has a severe deficiency of thyroid function, while even more have mild or partial degrees. If untreated for several months after birth, severe congenital hypothyroidism...

 can be endemic, genetic, or sporadic. If untreated, it results in mild to severe impairment of both physical and mental growth and development.

Poor length growth is apparent as early as the first year of life. Adult stature without treatment ranges from 1 to 1.6 metres (3'4 to 5'3), depending on severity, sex and other genetic factors. Bone maturation and puberty

Puberty

Puberty is the process of physical changes by which a child's body matures into an adult body capable of reproduction, as initiated by hormonal signals from the brain to the gonads; the ovaries in a girl, the testes in a boy...

 are severely delayed. Ovulation

Ovulation

Ovulation is the process in a female's menstrual cycle by which a mature ovarian follicle ruptures and discharges an ovum . Ovulation also occurs in the estrous cycle of other female mammals, which differs in many fundamental ways from the menstrual cycle...

 is impeded and infertility

Infertility

Infertility primarily refers to the biological inability of a person to contribute to conception. Infertility may also refer to the state of a woman who is unable to carry a pregnancy to full term...

 is common.

Neurological impairment may be mild, with reduced muscle tone and coordination, or so severe that the person cannot stand or walk. Cognitive impairment may also range from mild to so severe that the person is nonverbal and dependent on others for basic care. Thought and reflexes are slower.

Other signs may include thickened skin, enlarged tongue, or a protruding abdomen.

Sporadic and genetic cretinism results from abnormal development or function of the foetal thyroid gland. This type of cretinism has been almost completely eliminated in developed countries by early diagnosis by newborn screening

Newborn screening

Newborn screening is the process by which infants are screened shortly after birth for a list of disorders that are treatable, but difficult or impossible to detect clinically. Screening programs are often run by state or national governing bodies with the goal of screening all infants born in the...

 schemes followed by life long treatment with thyroxine

Thyroxine

Thyroxine, or 3,5,3',5'-tetraiodothyronine , a form of thyroid hormones, is the major hormone secreted by the follicular cells of the thyroid gland.-Synthesis and regulation:...

 (T4).

Thyroxine

Thyroxine

Thyroxine, or 3,5,3',5'-tetraiodothyronine , a form of thyroid hormones, is the major hormone secreted by the follicular cells of the thyroid gland.-Synthesis and regulation:...

 must be dosed as tablets only, even to newborns, as the liquid oral suspensions and compounded forms cannot be depended on for reliable dosing. In the case of dosing infants, the T4 tablets are generally crushed and mixed with breast milk, formula milk or water. If the medication is mixed with formulas containing iron or soya products, larger doses may be required, as these substances may alter the absorption of thyroid hormone from the gut. Frequent monitoring (every 2–3 weeks during the first months of life) is recommended to ensure that infants with congenital hypothyroidism remain within the high end of normal range, or euthyroid

Euthyroid

Euthyroid is the state of having normal thyroid gland function.Examples of a nonfunctioning thyroid gland may be hypothyroidism, hyperthyroidism, or thyroiditis....

.

Epidemiology

Cretinism arises from a diet deficient in iodine

Iodine

Iodine is a chemical element with the symbol I and atomic number 53. The name is pronounced , , or . The name is from the , meaning violet or purple, due to the color of elemental iodine vapor....

. It has affected many people worldwide and continues to be a major public health

Public health

Public health is "the science and art of preventing disease, prolonging life and promoting health through the organized efforts and informed choices of society, organizations, public and private, communities and individuals" . It is concerned with threats to health based on population health...

 problem in many countries. Iodine is an essential trace element, necessary primarily for the synthesis of thyroid hormones. Iodine deficiency is the most common preventable cause of brain damage worldwide. Although iodine is found in many foods, it is not universally present in all soils in adequate amounts. Most iodine, in iodide form, is in the oceans where the iodide ions oxidize to elemental iodine, which then enters the atmosphere and falls to earth as rain, introducing iodine to soils. Earth deficient in iodine is most common inland and in mountainous areas and areas of frequent flooding, but can also occur in coastal regions owing to past glaciation, and leaching by snow, water and heavy rainfall, which removes iodine from the soil. Plants and animals grown in iodine deficient soils are correspondingly deficient. Populations living in those areas without outside food sources are most at risk of iodine deficiency

Iodine deficiency

Iodine is an essential trace element; the thyroid hormones thyroxine and triiodotyronine contain iodine. In areas where there is little iodine in the diet—typically remote inlandareas where no marine foods are eaten—iodine deficiency gives rise to...

 diseases.

Iodine deficiency results in the impairments in varying degrees of physical and mental development. It also causes gradual enlargement of the thyroid gland, referred to as a goitre

Goitre

A goitre or goiter , is a swelling in the thyroid gland, which can lead to a swelling of the neck or larynx...

. It is being combated in many countries by public health campaigns of iodine administration.

History

Endemic cretinism was especially common in areas of southern Europe around the Alps and was described by ancient Roman writers, and often depicted by medieval artists. The earliest Alpine mountain climbers sometimes came upon whole villages of cretins. Alpine cretinism was described from a medical perspective by several travellers and physicians in the late 18th and early 19th centuries. At that time the cause was not known and it was often attributed to "stagnant air" in mountain valleys or "bad water." The proportion of people affected varied markedly throughout southern Europe and even within very small areas it might be common in one valley and not another. The number of severely affected persons was always a minority, and most persons were only affected to the extent of having a goitre and some degree of reduced cognition and growth. The majority of such cases were still socially functional in their pastoral villages.

Nineteenth century

More mildly affected areas of Europe and North America in the 19th century were referred to as "goiter belts". The degree of iodine deficiency was milder and manifested primarily as thyroid enlargement rather than severe mental and physical impairment. In Switzerland, for example, where soil does not contain a large amount of iodine, cases of cretinism were very abundant and even considered genetically caused. As the variety of food sources dramatically increased in Europe and North America and the populations became less than completely dependent on locally grown food, the prevalence of endemic goitre diminished.

Twentieth and twenty-first centuries

The early 20th century saw the discovery of the relationships of sporadic cretinism with congenital hypothyroidism, and of endemic cretinism with hypothyroidism due to iodine deficiency. Both have been largely eliminated in the developed world.

External links

• Network for Sustained Elimination of Iodine Deficiency
• Cretinism | Research in Mental Handicap