Growth hormone (GH) is a substance in the body that helps kids grow and develop.
It is made by the pituitary gland, a small gland between the lobes of the brain.
What Is Growth Hormone Deficiency?
GH deficiency happens when the body does not make enough growth hormone to allow
a child to grow at a normal pace.
The two kinds of GH deficiency are:
Congenital GH deficiency. This is the kind that some babies
are born with. They also can have problems with other hormones. Even though they're
born with the condition, some babies look like they're growing normally until they
are about 6 to 12 months old.
Acquired GH deficiency. This happens when the body stops
making enough GH to grow normally. It can start at any time in childhood.
What Are the Signs & Symptoms of Growth Hormone Deficiency?
Doctors check kids' height during regular
checkups. Over time, doctors can see how fast kids grow. If a child is growing
much slower than most other kids the same age, this is called growth failure.
One of the most visible signs of growth failure is a height that is much shorter
than most other kids the same age. This is called short stature.
But some kids can have growth failure even if they don't have short stature.
Other signs and symptoms of GH deficiency include:
delayed puberty (looking much younger than other kids the same age)
teeth that come in late
in boys, a small penis at birth
low blood sugars
What Causes Growth Hormone Deficiency?
Often, doctors don't know why a child has GH deficiency. When a cause is found,
it's often related to problems with the pituitary gland or with the brain around the
pituitary gland. Brain
tumors, head injuries, and radiation
treatment to the brain also can cause GH deficiency.
How Is Growth Hormone Deficiency Diagnosed?
If your child has growth failure or short stature, even without any other signs
or symptoms, your doctor might send you to a pediatric endocrinologist.
This is a doctor who specializes in children's growth and hormones.
will ask about your child's growth and will do a careful exam. The doctor
will order some tests to look for GH deficiency, such as:
Blood tests. There are no easy tests to measure GH levels. GH
is made in short bursts, mostly overnight. At other times, levels may be undetectable.
This makes testing for it hard, because there is no way to know when the bursts will
happen. So instead, doctors look at the levels of two proteins that have more stable
levels and are markers of GH function:
IGF-I, or insulin-like growth factor I
IGFPB-3, or insulin-like growth factor binding protein-3
Bone age X-rays. These are X-rays
of one of your child's hands and wrists. An expert compares your child's X-rays with
the X-rays of other children the same age, and gives the bones an age in years. If
a child's bone age is much younger than their actual age, this might be a sign of
GH stimulation test. Doctors do this test when other tests suggest
that a child might have GH deficiency. First, your child will need to fast by not
eating or drinking anything for a certain number of hours, usually overnight. The
doctor will give your child a medicine that should make the body produce a burst of
GH. A nurse will then draw blood at a few different times to check the GH levels to
try to catch the peak. Low GH levels confirm the diagnosis of growth hormone deficiency.
Brain MRI. This very detailed picture
of the brain helps doctors see if there is a problem with the pituitary gland
or the brain that might be causing GH deficiency.
How Is Growth Hormone Deficiency Treated?
Treatment for GH deficiency is a growth hormone shot every day. Parents learn how
to give these shots at home so they don't need to go to the doctor's office for them.
The endocrinologist will tell you how often your child should come in when treatment
starts. At each visit, the doctor:
will check your child's growth
may order blood tests to see how your child's body is responding to the medicine
change the dose, if needed
Side effects are rare at the doses used for growth hormone deficiency. Tell the
doctor if your child has headaches,
vision changes, or limping.
Treatment usually lasts until growth is completed, in the late teens.
What Else Should I Know?
Growth hormone can increase the speed of growth in a child with growth hormone
deficiency. Kids who start this treatment early often can catch up more than kids
who begin treatment later.
As adults, our bodies produce a much smaller amount of GH. So, many kids with GH
deficiency and no other medical problems who get GH shots won't need them as adults.