Growth hormone deficiency involves abnormally short stature with normal body proportions. Growth hormone deficiency may be congenital (present at birth) or acquired (the result of an injury or medical condition).
Panhypopituitarism; Dwarfism; Pituitary dwarfism
Causes, incidence, and risk factors:
An abnormally short height in childhood may occur if the pituitary gland does not produce enough growth hormone . Most of the time, no underlying cause is found, but it can be caused by absence of the pituitary gland or severe brain injury.
Growth retardation may first be noticed in infancy and continue throughout childhood. The child's "growth curve," which is usually plotted on a standardized growth chart by the pediatrician, may range from flat (no growth) to very shallow (minimal growth). Normal puberty may or may not occur, depending on how well the pituitary gland can produce adequate hormone levels other than growth hormone.
Growth hormone deficiency may be associated with deficiencies of other hormones, including the following:
- Thyrotropins (control production of thyroid hormones)
- Vasopressin (controls water balance in the body)
- Gonadotropins (control production of male and female sex hormones)
- ACTH or adrenocorticotrophic hormone (controls the adrenal gland and its production of cortisol, DHEA, and other hormones)
Physical defects of the face and skull can also be associated with pituitary gland or pituitary function abnormalities. A small percentage of infants with cleft lip and cleft palate have decreased growth hormone levels.
Although it is uncommon, growth hormone deficiency may also be diagnosed in adults. Possible causes include:
- Hormonal problems involving the pituitary gland or the hypothalamus
- Receiving brain radiation treatments for cancer
- Severe head injury
Signs and tests:
A physical examination including weight, height, and body proportions will show signs of slowed growth rate and deviation from normal growth curves.
Tests may include the following:
- DEXA (dual energy x-ray absorptiometry) can also determine bone age.
- Hand x-ray can determine bone age.
- Measurement of growth hormone and associated binding protein levels (IGF-I and IGFBP-3) reveals if the growth problem is caused by dysfunction of the pituitary gland.
- MRI of the head can show the hypothalamus and pituitary glands.
- Tests to measure other hormone levels (lack of growth hormone may not be the only problem).
- X-ray of head may show problems with the skull, such as small, enlarged, or empty sella , or a space-occupying lesion.
Synthetic growth hormone can be used for children with growth hormone deficiency. This treatment requires the assistance of a pediatric endocrinologist. Treatment with synthetic (recombinant) human growth hormone is generally considered to be safe. Side effects are rare.
If growth hormone is deficient, only synthetic growth hormone is given. If other hormones are also deficient, additional hormone replacement preparations are required.
Growth rates are improved in most children treated with growth hormones, although the effectiveness may decrease with prolonged treatment.
If left untreated, extremely short stature and delayed puberty will result from this condition.
In the past, some patients acquired Creutzfeldt-Jacob disease (the human form of "mad cow" disease) from human-derived growth hormone that was used to treat growth deficiencies. This medication has been removed from the market.
Synthetic growth hormone is used instead and carries no risk of infectious disease.
Calling your health care provider:
Call your health care provider if your child seems abnormally short for his or her age.
Most cases are not preventable.
Review your child's growth chart with your physician after each check-up. If your child's growth rate is dropping or your child's projected adult height is much shorter than an average height of both parents, evaluation by a specialist is recommended.
Adjusted average height of both parents is as follows:
- For boys:
- Mom's height (in inches) plus 5 inches + Dad's height (in inches). Divide the end number by 2.
- For girls:
- Dad's height (in inches) minus 5 inches + Mom's height (in inches). Divide the end number by 2.