Endocrine Diseases
Dwarfism
is a condition characterized by short stature. Technically, that means an adult height of 4 feet 10 inches or under, according to the advocacy group Little People of America (LPA).
can be caused by any one of more than 200 conditions, most of which are genetic. The most common type, accounting for 70% of all cases of short stature, is called achondroplasia.
can and most often does occur in families where both parents are of average height. In fact, 85% of children with achondroplasia are born to average-size parents.
Achondroplasia is a genetic disorder of bone growth that is evident at birth. It affects about 1 in 15,000 to 1 in 40,000 births, and it occurs in all races and in both sexes (1). Its depiction in ancient Egyptian art makes it one of the oldest recorded birth defects.
Achondroplasia is the most common of a group of growth defects characterized by abnormal body proportions. Affected individuals have arms and legs that are very short, while the torso is nearly normal size.
The word achondroplasia is Greek and means "without cartilage formation," although individuals with achondroplasia do have cartilage. During fetal development and childhood, cartilage normally develops into bone, except in a few places, such as the nose and ears. In individuals with achondroplasia, something goes wrong during this process, especially in the long bones (such as those of the upper arms and thighs). The rate at which cartilage cells in the growth plates of the long bones turn into bone is slow, leading to short bones and reduced height.
What does a person with achondroplasia look like?
A child with achondroplasia has a relatively normal torso and short arms and legs. The upper arms and thighs are more shortened than the forearms and lower legs. Generally, the head is large, the forehead is prominent and the nose is flat at the bridge. Sometimes, the large head size reflects hydrocephalus (excess fluid in the brain) and requires surgery. Hands are short with stubby fingers. There is a separation between the middle and ring fingers (trident hand). Feet are generally short, broad and flat. Most individuals with achondroplasia eventually reach an adult height of about 4 feet (1, 2).
What is the cause of achondroplasia?
Achondroplasia is caused by a mutation in a gene (called fibroblast growth factor receptor 3) that is located on chromosome 4 (5, 6). This gene normally helps regulate the rate of growth in long bones. Mutations in this gene result in severely limited bone growth.
Achondroplasia is a genetic disorder of bone growth that is evident at birth. It affects about 1 in 15,000 to 1 in 40,000 births, and it occurs in all races and in both sexes (1). Its depiction in ancient Egyptian art makes it
individuals with achondroplasia eventually reach an adult height of about 4 feet (1, 2).
What is the cause of achondroplasia?
Achondroplasia is caused by a mutation in a gene (called fibroblast growth factor receptor 3) that is located on chromosome 4 (5, 6). This gene normally helps regulate the rate of growth in long bones. Mutations in this gene result in severely limited bone growth.
In a small number of cases, a child inherits achondroplasia from a parent who also has the condition. If one parent has the condition and the other does not, there is a 50 percent chance that their child will be affected. If both parents have achondroplasia, there is:
is a condition characterized by short stature. Technically, that means an adult height of 4 feet 10 inches or under, according to the advocacy group Little People of America (LPA).
can be caused by any one of more than 200 conditions, most of which are genetic. The most common type, accounting for 70% of all cases of short stature, is called achondroplasia.
can and most often does occur in families where both parents are of average height. In fact, 85% of children with achondroplasia are born to average-size parents.
Achondroplasia is a genetic disorder of bone growth that is evident at birth. It affects about 1 in 15,000 to 1 in 40,000 births, and it occurs in all races and in both sexes (1). Its depiction in ancient Egyptian art makes it one of the oldest recorded birth defects.
Achondroplasia is the most common of a group of growth defects characterized by abnormal body proportions. Affected individuals have arms and legs that are very short, while the torso is nearly normal size.
The word achondroplasia is Greek and means "without cartilage formation," although individuals with achondroplasia do have cartilage. During fetal development and childhood, cartilage normally develops into bone, except in a few places, such as the nose and ears. In individuals with achondroplasia, something goes wrong during this process, especially in the long bones (such as those of the upper arms and thighs). The rate at which cartilage cells in the growth plates of the long bones turn into bone is slow, leading to short bones and reduced height.
What does a person with achondroplasia look like?
A child with achondroplasia has a relatively normal torso and short arms and legs. The upper arms and thighs are more shortened than the forearms and lower legs. Generally, the head is large, the forehead is prominent and the nose is flat at the bridge. Sometimes, the large head size reflects hydrocephalus (excess fluid in the brain) and requires surgery. Hands are short with stubby fingers. There is a separation between the middle and ring fingers (trident hand). Feet are generally short, broad and flat. Most individuals with achondroplasia eventually reach an adult height of about 4 feet (1, 2).
What is the cause of achondroplasia?
Achondroplasia is caused by a mutation in a gene (called fibroblast growth factor receptor 3) that is located on chromosome 4 (5, 6). This gene normally helps regulate the rate of growth in long bones. Mutations in this gene result in severely limited bone growth.
Achondroplasia is a genetic disorder of bone growth that is evident at birth. It affects about 1 in 15,000 to 1 in 40,000 births, and it occurs in all races and in both sexes (1). Its depiction in ancient Egyptian art makes it
individuals with achondroplasia eventually reach an adult height of about 4 feet (1, 2).
What is the cause of achondroplasia?
Achondroplasia is caused by a mutation in a gene (called fibroblast growth factor receptor 3) that is located on chromosome 4 (5, 6). This gene normally helps regulate the rate of growth in long bones. Mutations in this gene result in severely limited bone growth.
In a small number of cases, a child inherits achondroplasia from a parent who also has the condition. If one parent has the condition and the other does not, there is a 50 percent chance that their child will be affected. If both parents have achondroplasia, there is:
- A 50 percent chance that the child will inherit the condition
- A 25 percent chance that the child will not have it
- A 25 percent chance that the child will inherit one abnormal gene from each parent and have severe skeletal abnormalities that lead to early death
Giantism
Gigantism is abnormally large growth due to an excess of growth hormone during childhood, before the bone growth plates have closed.
The most common cause of too much growth hormone release is a noncancerous (benign) tumor of the pituitary gland.
If excess growth hormone occurs after normal bone growth has stopped, the condition is known as Acromegaly.
The child will grow in height, as well as in the muscles and organs. This excessive growth makes the child extremely large for his or her age.
Other symptoms include:
- Delayed puberty
- Double vision or difficulty with side (peripheral) vision
- Frontal bossing (Frontal bossing is an unusually prominent forehead, sometimes associated with a heavier than normal brow ridge.)and a prominent jaw
- Headache
- Increased sweating
- Irregular periods (menstruation)
- Large hands and feet with thick fingers and toes
- Release of breast milk
- Thickening of the facial features
- Weakness
Acromegaly is a chronic metabolic disorder in which there is too much growth hormone and the body tissues gradually enlarge.
The cause of the increased growth hormone release is usually a noncancerous (benign) tumor of the pituitary gland. The pituitary gland, which is located just below the brain, controls the production and release of several different hormones, including growth hormone.
The cause of the increased growth hormone release is usually a noncancerous (benign) tumor of the pituitary gland. The pituitary gland, which is located just below the brain, controls the production and release of several different hormones, including growth hormone.
Goiter Simple Goiter The thyroid can become very large so that it can easily be seen as a mass in the neck. This picture depicts the outline of a normal size thyroid in black and the greatly enlarged goiter in pink. There are a number of factors which may cause the thyroid to become enlarged. A diet deficient in iodine can cause a goiter but this is rarely the cause because of the readily available iodine in our diets. A more common cause of goiter in America is an increase in thyroid stimulating hormone (TSH) in response to a defect in normal hormone synthesis within the thyroid gland. The thyroid stimulating hormone comes from the pituitary and causes the thyroid to enlarge. This enlargement usually takes many years to become manifest. There are two types of simple goiter:
The use of iodized table salt in the United States today prevents iodine deficiency. However, the Great Lakes, Midwest, and inner mountain areas of the United States were once called the "goiter belt," because a high number of goiter cases occurred there. A lack of enough iodine is still common in central Asia, the Andes region of South America, and central Africa. For more information on this type of goiter, see: Colloid nodule goiter. In most cases of sporadic goiter the cause is unknown. Occasionally, certain medications such as lithium or aminoglutethimide can cause a nontoxic goiter. Inherited factors may cause goiters. Risk factors include:
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Exopthalmic Goiter
A disease of the thyroid gland consisting of hyper-thyroidism, exophthalmos(eyes pushed outwards) and goiterous enlargement of the thyroid gland. A diffuse primary hyperplasia of the thyroid gland of obscure origin; may occur at any age. It produces nervousness, muscular weakness, heat intolerance, tremor, loss of weight, lid lag, and absence of winking and may lead to thyrotoxic heart disease and thyroid crisis.
A disease of the thyroid gland consisting of hyper-thyroidism, exophthalmos(eyes pushed outwards) and goiterous enlargement of the thyroid gland. A diffuse primary hyperplasia of the thyroid gland of obscure origin; may occur at any age. It produces nervousness, muscular weakness, heat intolerance, tremor, loss of weight, lid lag, and absence of winking and may lead to thyrotoxic heart disease and thyroid crisis.
Diabetes Mellitus
Diabetes mellitus is a group of metabolic diseases characterized by high blood sugar (glucose) levels, that result from defects in insulin secretion, or action, or both. Diabetes mellitus is a common, and serious disease in which blood glucose levels are not regulated. the body may produce insufficient amounts of Insulin to process blood glucose, or the body's tissues may not use insulin properly. Diabetes mellitus has been known as "sugar diabetes," a misnomer because diabetes is not linked directly with the consumption of sugar. Because it can cause a disease of blood vessels most evident in the eyes and kidneys, diabetes is the most frequent cause of blindness and a common cause of kidney failure. Because of diabetic complications and the rapid development of arteriosclerosis in inadequately treated diabetic patients, it is one of the most significant causes of death in Canada. Type 1 Type 1 diabetes mellitus can occur at any age and is characterized by the marked and progressive inability of the pancreas to secrete insulin because of autoimmune destruction of the beta cells. Type 2 Type 2 diabetes mellitus occurs when the pancreas (an organ in the abdomen) produces insufficient amounts of the hormone insulin and/or the body's tissues become resistant to normal or even high levels of insulin (figure 1). This causes high blood glucose (sugar) levels, which can lead to a number of complications if untreated. |