Understanding growth hormone deficiency in children.
Sometimes children’s bodies don’t make enough growth hormone.
Why does it happen?
“Deficiency” simply means not enough of something. Children with growth hormone deficiency don’t make enough growth hormone on their own. Growth hormone deficiency affects at least one in 3,480 children in the United States.
Some reasons for growth hormone deficiency include:
- Lack of glandular development. Sometimes children are born with growth hormone deficiency because their pituitary gland or hypothalamus gland is not fully developed.
- Glandular trauma or impediment. Growth hormone deficiency may develop after birth because of damage to the brain from head trauma, a serious brain infection, or even a brain tumor.
Ask questions: Talk to your child's doctor for further information about the causes of growth hormone deficiency.
Results of growth hormone deficiency.
When the body doesn’t have enough growth hormone, cells do not grow or do not grow enough. This affects much more than height; it affects many parts of the body. Lack of treatment for growth hormone deficiency could result in a child’s being significantly shorter than they would otherwise be when they reach adulthood.
How growth hormone deficiency is diagnosed.
If you were the first to notice your child’s lack of growth, you’ll want to talk to your child’s primary care physician as soon as possible. He or she will refer your child to a pediatric endocrinologist (a doctor who specializes in diseases related to hormones) for the actual diagnosis.
The endocrinologist will take a family and medical history. Most likely, they’ll also take an X-ray of your child’s hand and wrist, to determine the bone age. There may also be blood tests done to help determine if there is a growth problem and if that problem is related to growth hormone deficiency.
The “stim” test.
The pituitary gland produces growth hormone in different amounts at different times of the day. This makes it difficult to test the amount of growth hormone the pituitary gland is releasing with just one blood sample. So, endocrinologists perform what is called a stimulation test or "stim" test, which uses a series of blood samples, to get a more accurate picture.a There is no one approved method for stim testing, but here’s an example of what might occur (talk with your health care provider for specific information):
- Your child will be given an IV and the first blood sample will be taken.
- Then, the stimulating medicine will be given. Your child will be closely monitored for any side effects that may occur.
- Blood samples will be taken over the next few hours. Your child will be able to rest or do quiet activities during this time.
- When the last blood sample has been taken and the test is over, the IV will be removed.
- The doctor will communicate with you about when you’ll receive the results of the test and what the next steps will be.
a With all medicines, there are benefits to using them; however, there may be side effects. The medicines used during the stim test may cause side effects. If you have any questions, ask your health care provider.
Preparing for the test.
- Explain the test to your child, including why it’s being given. Talk about the IV. You may want to demonstrate on a doll. Your child’s doctor will likely recommend that he or she not eat and limit physical activity for 10 - 12 hours before the test, to avoid changing the results.
- Keep in mind that the test will take at least several hours and sometimes can take most of a day. You might consider bringing activities for yourself and your child to keep busy while you’re waiting.