Growth Hormone Antibody
Does this test have other names?
Anti-human GH antibodies, growth hormone neutralizing antibodies
What is this test?
This test looks for growth hormone (GH) antibodies in your blood.
GH is used to manage height issues linked to a growth hormone deficiency (GHD). If
your body makes GH antibodies in response to GH treatment, the treatment may not work
the way it should.
Why do I need this test?
You might have this test if your healthcare provider suspects that your GH treatment
isn't working anymore. The most common symptom of GH antibodies is a lack of growth
even with adequate doses of GH.
Children with GHD often fail to grow on a normal schedule. Signs include an abnormal
weight-to-height ratio and immature facial structure, notably a large forehead and
an underdeveloped nose bridge. A child's voice may not mature, his or her hair may
not grow well, and the transition to adolescence is often delayed.
Ten to 20 percent of people who get GH therapy will develop GH antibodies in reaction
to it. This often happens soon after GH treatment starts—usually after a three- to
six-month growth period. The antibodies can cause the treatment to not work.
The good news is that GH antibodies are becoming increasingly rare thanks to the use
of a synthetic, or man-made, growth hormone.
What other tests might I have along with this test?
Your healthcare provider may also order a blood test for insulin-like growth factor
I (IGF-I). Low levels of IGF-I can be a sign that the GH may not be working the way
What do my test results mean?
Many things may affect your lab test results. These include the method each lab uses
to do the test. Even if your test results are different from the normal value, you
may not have a problem. To learn what the results mean for you, talk with your healthcare
Normal results are negative, meaning that no GH antibodies were found. Positive results
mean that GH antibodies were found and that your GH therapy may no longer be working.
How is this test done?
The test requires a blood sample, which is drawn through a needle from a vein in your
Does this test pose any risks?
Taking a blood sample with a needle carries risks that include bleeding, infection,
bruising, or feeling dizzy. When the needle pricks your arm, you may feel a slight
stinging sensation or pain. Afterward, the site may be slightly sore.
What might affect my test results?
Other factors aren't likely to affect your results.
How do I get ready for this test?
You don't need to prepare for this test.