In some cases, there is no clear cause identified. Sometimes, GHD can be associated with lower levels of other hormones, such as vasopressin which controls water production in the body , gonadotropins which controls the production of male and female sex hormones , thyrotropins which control the production of thyroid hormones or adrenocorticotrophic hormone which controls the adrenal gland and related hormones.
Symptoms of other pituitary hormone deficiencies that may co-exist with growth hormone deficiency:. Facial abnormalities can be present in a small group of children with GHD, typically caused by pituitary defects.
A physical exam and measurement of height, weight, arms and leg lengths are the first steps to diagnosis, in addition to thorough medical history. Blood tests to measure the levels of growth hormone in the body as well as the levels of other hormones. A person with achondroplasia and with two average-size parents received one mutated copy of the gene associated with the disorder and one normal copy of the gene.
A person with the disorder may pass along either a mutated or normal copy to his or her own children. Turner syndrome, a condition that affects only girls and women, results when a sex chromosome the X chromosome is missing or partially missing. A female inherits an X chromosome from each parent. A girl with Turner syndrome has only one fully functioning copy of the female sex chromosome rather than two. The cause of growth hormone deficiency can sometimes be traced to a genetic mutation or injury, but for most people with the disorder, no cause can be identified.
Other causes of dwarfism include other genetic disorders, deficiencies in other hormones or poor nutrition. Sometimes the cause is unknown. Complications of dwarfism-related disorders can vary greatly, but some complications are common to a number of conditions. The characteristic features of the skull, spine and limbs shared by most forms of disproportionate dwarfism result in some common problems:.
With proportionate dwarfism, problems in growth and development often result in complications with poorly developed organs. For example, heart problems that often occur with Turner syndrome can have a significant effect on health. An absence of sexual maturation associated with growth hormone deficiency or Turner syndrome affects both physical development and social functioning.
Women with disproportionate dwarfism may develop respiratory problems during pregnancy. A C-section cesarean delivery is almost always necessary because the size and shape of the pelvis doesn't allow for successful vaginal delivery.
Most people with dwarfism prefer not to be labeled by a condition. However, some people may refer to themselves as dwarfs, little people or people of short stature. The word "midget" is generally considered an offensive term. People of average height may have misconceptions about people with dwarfism.
And the portrayal of people with dwarfism in modern movies often includes stereotypes. Misconceptions can impact a person's self-esteem and limit opportunities for success in school or employment. Children with dwarfism are particularly vulnerable to teasing and ridicule from classmates. Because dwarfism is relatively uncommon, children may feel isolated from their peers. Mayo Clinic does not endorse companies or products.
Advertising revenue supports our not-for-profit mission. This content does not have an English version. This content does not have an Arabic version. Overview Dwarfism is short stature that results from a genetic or medical condition. Request an Appointment at Mayo Clinic. Share on: Facebook Twitter. Therefore, pituitary dwarfism is decreased bodily growth due primarily to hormonal problems.
The end result is a proportionate little person, because the height and the growth of all other structures of the individual are decreased. Pituitary dwarfism is caused by problems arising from the pituitary gland. The pituitary gland, also called the hypophysis, is a gland at the base of the brain that produces many different hormones. This gland is divided into the anterior front and posterior back halves. The anterior pituitary produces six hormones: growth hormone, adrenocorticotropin corticotropin , thyroid stimulating hormone thyrotropin , prolactin, follicle stimulating hormone, and lutenizing hormone.
The posterior pituitary gland only produces two hormones: antidiuretic hormone vasopressin and oxytocin. The growth process begins in the lower part of the forebrain in a small organ called the hypothalamus. The hypothalamus releases hormones that regulate the production of other hormones. When the hypothalamus releases growth hormone-releasing hormone GHRH , the anterior pituitary is stimulated to release growth hormone GH.
Growth hormone then acts on the liver and other tissues and stimulates them to secrete insulin-like growth factor-1 IGF IGF-1 directly promotes the development of bone and muscle, causing bones to grow in length, and muscles to increase protein synthesis make more protein. Since growth is a complex phenomenon, it may be slowed down or stopped by abnormalities arising at any point in the process. Thus, dwarfism can result if there is a deficiency in any of these hormones, if there is a failure in the receptor cells receiving the hormonal stimuli, or if the target cells are unable to respond.
At its most basic, pituitary dwarfism results from decreased production of hormones by the anterior pituitary. When none of the hormones of the anterior pituitary are adequately produced, this is called panhypopituitarism.
A common form of pituitary dwarfism is due to deficiencies in the production of growth hormone GH. When less GH than normal is produced during childhood, an individual's arms, legs, and other structures continue to develop in normal proportions, but at a decreased rate. It is estimated that between one in 14, and one in 27, babies born each year have some form of dwarfism. In , more than 20, children in United States were receiving supplemental GH therapy.
It is estimated that about one quarter of them had organic causes of GH deficiencies. There appears to be no racial or ethnic component to pituitary dwarfism, but males seem to be afflicted more than females. Investigations are underway to determine the specific genetic mutations that can cause dwarfism.
Pituitary dwarfism can be caused by:. A child with a growth hormone deficiency is often small with an immature face and chubby body build. The child's growth does not follow the normal growth curve patterns. In cases of tumor, most commonly craniopharyngioma a tumor near the pituitary gland , children and adolescents may have neurological symptoms such as headaches, vomiting , and problems with vision. The child may also have symptoms of double vision.
The symptom, however, that all children with pituitary dwarfism share is that they do not grow at the same rate as their peers.
If a child appears to be smaller than children two or more years younger than he or she is, the doctor should be consulted. Growth hormone deficiency is present at birth, but since the primary symptoms of pituitary dwarfism are height and growth at a reduced rate, the condition is not diagnosed until later in childhood.
Charting a child's growth in comparison to age norms will help lead to a diagnosis. Another diagnostic technique uses an x ray of the child's hand to determine the child's bone age by comparing this to the child's actual chronological age. The bone age in affected children is usually two or more years behind the chronological age. This means that if a child is 10 years old, his or her bones will look like they are those of an eight-year-old.
The levels of growth hormone and IGF-1 may also be measured with blood tests. The doctor will do a complete examination to make sure that delayed growth is not caused by other underlying problems, such as tumor. X rays of the area where the pituitary gland is located, or more advanced imaging such as magnetic resonance imaging MRI or computed tomography CT , may help the doctor make a diagnosis and may show whether there have been any changes to the pituitary gland itself.
Growth hormone replacement therapy can be administered if the child is lacking growth hormone. A pediatric endocrinologist, a doctor specializing in the hormones of children, administers this type of therapy before a child's bone growth plates have fused or joined.
Once the growth plates have fused, GH replacement therapy is rarely effective.
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