Med-Surg Endocrine System, part 9: Growth Hormone Deficiency and Excess

Updated:

In this article, we explain growth hormone deficiency and growth hormone excess for nurses and nursing students. These are disorders that result from improper amounts of growth hormone in the body. Knowing the pathophysiology, symptoms, diagnosis and treatment for these two disorders will be key in your Med-Surg exams as well as your nursing practice.

These disorders are covered in our Medical-Surgical Flashcards (Endocrine system).

Growth Hormone Deficiency

What is growth hormone deficiency?

Growth hormone deficiency occurs when the anterior pituitary gland secretes an inadequate amount of growth hormone. It may be caused by a congenital disorder. It may also be due to trauma to the pituitary gland.

Growth hormone deficiency can also be caused by a problem with the hypothalamus. If you recall from our overview on growth hormone (GH), the hypothalamus releases growth hormone-releasing hormone (GHRH), which causes GH to be produced in the anterior pituitary gland. So if the hypothalamus has a problem, it will not produce enough GHRH to instruct the pituitary gland to release GH, resulting in a GH deficiency.

Signs and symptoms of growth hormone deficiency

The primary symptom with growth hormone deficiency is a patient with short stature but proportional height and weight. Other signs and symptoms include reduced muscle mass and increased body fat. Because growth hormone plays such an important part in the puberty process, the onset of puberty may also be delayed.

Diagnosis of growth hormone deficiency

To diagnose growth hormone deficiency, there are several options available, including a growth hormone stimulation test, a bone age scan, or a CT scan of the patient’s head to look for abnormalities in the hypothalamus or pituitary gland.

A growth hormone stimulation test triggers the pituitary gland to produce GH and then evaluates the amount that is produced.

A bone age scan is an X-ray that assesses the maturity of the patients’ skeleton to see if it is appropriate for the patient’s age.

Treatment for growth hormone deficiency with Somatropin

A patient with growth hormone deficiency will need growth hormone replacement therapy. The drug for this is called somatropin, which can be used on children and adults, and is administered subcutaneously. Somatropin is used for growth hormone deficiency because it is similar to naturally occurring GH; it stimulates growth and anabolism. Some side effects that somatropin can cause are hyperglycemia and pancreatitis.

Somatropin is just one of the hundreds of medications covered in our Pharmacology Flashcards.

When to stop administering somatropin

Throughout the growth hormone replacement therapy, the patient will have X-rays done so that growth rate and bone age can be monitored. The epiphyseal plate, also known as the growth plate, is a section on the end of long bones that allows the bones to grow. Epiphyseal closure, when these plates close, is when bones stop lengthening.

When the patient is taking somatropin, it is important these X-rays be monitored for the epiphyseal closure. Stop treatment with somatropin prior to epiphyseal closure.

Growth Hormone Excess

What is growth hormone excess?

Growth hormone excess is excess secretion of GH from the anterior pituitary gland. Growth hormone excess causes increased growth of bone and cartilage, as well as increased protein synthesis.

What causes growth hormone excess?

Growth hormone excess is usually due to a tumor or lesion in the pituitary gland that causes it to pump out extra growth hormone.

More rarely, growth hormone excess can be caused by hypothalamus dysfunction. If the hypothalamus produces too much growth hormone-releasing hormone, that causes excess growth hormone to be produced in the pituitary gland.

Signs and symptoms of growth hormone excess

Signs and symptoms of growth hormone excess depend on the onset of this disorder.

Gigantism

Growth hormone excess that occurs prior to the epiphyseal growth plate closure results in gigantism. Remember, epiphyseal closure is when the bones stop growing. So growth hormone excess that occurs before the bones stop lengthening can result in gigantism. The important signs and symptoms to know for this are excessive height (because skeletal growth velocity increases and the bones are still able to lengthen) and arthritis.

Acromegaly

Growth hormone excess that occurs after growth plate closure results in acromegaly. The signs and symptoms to know for acromegaly are enlarged hands and feet, a protruding jaw, kyphosis (abnormal curvature of the thoracic spine), arthritis, and an enlarged larynx. The enlarged larynx causes a deep, hollow voice.

Famous person with acromegaly

In the movie Princess Bride (one of Cathy’s favorites!) the giant Fezzik is played by Andre the Giant. Andre the Giant has acromegaly, with the deep and hollow voice, enlarged hands and feet, and kyphosis. Check it out, and that will help you remember the signs and symptoms of acromegaly.

Diagnosis of growth hormone excess

To diagnose growth hormone excess, the patient can get a CT/MRI of the pituitary gland to see if there is an abnormality like a lesion or tumor.

Treatment for growth hormone excess

The treatment for growth hormone excess is a hypophysectomy to remove all or part of the pituitary gland, if necessary. Learn more about hypophysectomy surgery.

Cathy’s teaching on these disorders is intended to help prepare you for Medical-Surgical nursing exams. The Medical-Surgical Nursing video series is intended to help RN and PN nursing students study for nursing school exams, including the ATI, HESI and NCLEX.

Full Transcript: Med-Surg Endocrine System, part 9: Growth Hormone Deficiency and Excess

Okay. In this video, we are going to talk about growth hormone deficiency as well as growth hormone excess.

Growth hormone deficiency is where we have inadequate secretion of growth hormone from the anterior pituitary gland. This may be due to a congenital disorder. It may also be due to injury or damage to the pituitary gland, or it could be due to an issue with the hypothalamus.

If you recall, the hypothalamus produces growth hormone-releasing hormone, or GHRH, and this allows for secretion of growth hormone. If we are not producing GHRH due to some issue with the hypothalamus, then the pituitary gland is not getting the signal it needs to produce growth hormone.

So in terms of signs and symptoms of growth hormone deficiency, the primary thing we'll see is short stature in our patient but proportional height and weight. Other signs and symptoms may include reduced muscle mass, increased fat, and delayed puberty.

So in terms of diagnosing this condition, we could do a growth hormone stimulation test as well as a bone age scan, and we could do a CT scan of the patient's head to take a look for abnormalities in the hypothalamus or the pituitary gland.

In terms of treatment, we need to provide growth hormone replacement therapy. This is done with a drug called somatropin. We administer this through a subcutaneous route.

If you want more details about somatropin, you'll notice here, on the back of card 21 if you're following along with cards [in our Medical-Surgical flashcards], there's a reference to Pharm card 109 [in our Pharmacology flashcards], and that card has information about somatropin.

But some of the key points about administering somatropin, besides the fact that it's administered subcutaneously, is that we typically stop treatment with somatropin once X-rays show epiphyseal closure.

So we would be doing X-rays throughout the therapy with the growth hormone replacement, and when we see that epiphyseal closure, that's typically when we terminate treatment with somatropin.

Now let's talk about growth hormone excess. This is where we have excess secretion of GH from the anterior pituitary gland, and this may be due to some kind of tumor or lesion in the pituitary gland. That is most likely. But it could also be due to some kind of dysfunction in the hypothalamus. So if the hypothalamus produces too much growth hormone-releasing hormone, that causes excess growth hormone to be produced in the pituitary gland. So when we have excess growth hormone, this causes increased growth of bone and cartilage as well as increased protein synthesis.

Signs and symptoms will depend on when we had the onset of this disorder.

So if we have growth hormone excess prior to epiphyseal growth plate closure, this results in gigantism. And key signs and symptoms of gigantism include excessive height and arthritis.

However, if we have onset of growth hormone excess after growth plate closure, this results in acromegaly. And signs and symptoms of acromegaly include enlarged hands and feet, a protruding jaw, kyphosis, which is an abnormal curvature of the thoracic spine, arthritis, as well as an enlarged larynx. So this enlarged larynx can cause a deep and hollow voice.

So one of my favorite movies of all time is Princess Bride. If you haven't seen it, I totally recommend it. But Andre the Giant is a key actor in this movie, and he has acromegaly. So he has that deep and hollow voice. He definitely has enlarged hands and feet and that kyphosis. So check it out, and that will help you to remember the signs and symptoms of acromegaly.

So to diagnose this condition, we would do a CT or MRI of the pituitary gland to basically see if we have got some kind of lesion or tumor there.

And then, for treatment, we would do a hypophysectomy to remove part of the pituitary gland or all of the pituitary gland, if necessary.

Alright. So that is it for this video. We will pick it up with diabetes insipidus and SIADH in my next video. Thanks so much for watching!

Back to blog

Leave a comment

Please note, comments need to be approved before they are published.