What is Acromegaly? Symptoms & Treatments

Acromegaly is a rare, slowly progressive hormonal disorder that occurs when there is too much growth hormone in the body. It causes bones and soft tissues in the body to grow abnormally, resulting in enlarged hands and feet, changes in facial features, and other symptoms. Please continue reading to learn more about this condition.

What are normal growth hormone levels?

The pituitary gland is a small gland located at the base of the brain. Normal pituitary function is needed for many body processes, such as growth, metabolism, and reproduction. The pituitary gland releases eight different hormones, including the growth hormone (GH), also called the human growth hormone or somatotropin. In addition, the pituitary makes other hormones such as thyroid-stimulating hormone, follicle-stimulating hormone, luteinizing hormone, prolactin, and adrenocorticotropic hormone.

Growth hormone (GH) regulates height, bone length, and muscle growth and causes a child to grow. Growth hormone levels are high during childhood and peak during puberty when the pituitary gland makes more growth hormone to support physical growth. However, adults continue to need this natural hormone after they have stopped growing to maintain healthy bones and tissues, regulate metabolism, and keep blood sugar levels in a healthy range.

The normal range of growth hormone levels is 10-50 ng/mL in children, 1-14 ng/mL in adult women, and 0.4-10 ng/mL in adult men.

Both too little and excess GH can cause problems. When the pituitary gland produces too much GH, it causes gigantism in children and acromegaly in adults. Too little growth hormone can result in dwarfism and slow growth.

What is the most common cause of acromegaly?

The most common cause of acromegaly is a non-cancerous pituitary tumor called a pituitary adenoma which makes excess growth hormone. Pituitary adenomas are the cause of 90% of cases of acromegaly. Less commonly, non-pituitary tumors, for example, in the adrenal glands, lungs, or pancreas, produce growth hormone or growth hormone-releasing hormone (GHRH), which signals the pituitary to make more growth hormone.

Growth hormone signals the liver to make a hormone called insulin-like growth factor 1 (IGF-1). It is IGF-1 that causes the symptoms of acromegaly, such as the abnormal growth of bones and body tissues. It also affects how the body processes glucose (sugar) and lipids (fats). Therefore, too much growth hormone leads to high IGF-I levels, which can result in high blood pressure, high blood sugar, heart disease, and other complications.

How do you know if you have acromegaly (too much growth hormone)?

It can be difficult to know that you have acromegaly at first because the symptoms of excess growth hormone start slowly. You may notice subtle changes such as your rings not fitting, your shoes becoming tighter, or your jaw becoming more prominent. If you notice these signs, make an appointment to see your healthcare provider.

How is acromegaly diagnosed?

If your provider suspects acromegaly, they may refer you to an endocrinologist or specialist in digestive and kidney diseases, even a neurosurgeon. A diagnosis of acromegaly can be made with a thorough clinical evaluation, blood tests, a glucose tolerance test, imaging studies such as X-rays and magnetic resonance imaging, sleep study, colonoscopy, echocardiogram, and DXA scan.

What are the symptoms of acromegaly?

The symptoms of acromegaly (growth hormone excess) include:

Enlarged hands and feet
Changes in facial features, for example, increased prominence of the forehead and jaw
Dough-like consistency of the limbs due to soft tissue swelling
Enlargement of the lips, nose, and tongue
Deepening or huskiness of the voice
Excessive sweating and body odor
Coarse, thickened, and oily skin due to excess sebaceous glands

Additionally, symptoms of acromegaly can also include the following if the pituitary adenoma presses on other pituitary tissue (surrounding tissue) or there is an excess of other pituitary hormones:

Severe and persistent headaches
Vision changes
Joint pain, muscle aches, weakness, limited mobility
Increased number of skin tags
Numbness in the hands and feet
Sleep apnea
Carpal tunnel syndrome
Menstrual cycle irregularities in women
Erectile dysfunction men
Low libido (loss of interest in sex)

What is the current treatment for acromegaly?

Acromegaly treatment consists of the following:

Surgery to remove a pituitary adenoma that is making too much growth hormone.
Radiation therapy to reduce the size of the tumor and treat acromegaly.
Medications such as growth hormone receptor antagonists (pegvisomant), dopamine agonists (bromocriptine, cabergoline, quinagolide), and somatostatin analogs (octreotide, lanreotide). These medications help normalize growth hormone levels and provide relief from symptoms of acromegaly.

What is the first treatment for acromegaly?

The first treatment in acromegaly depends on the nature and severity of your symptoms. Your healthcare providers will formulate a treatment plan based on your individual case. This may include surgery to remove a pituitary tumor causing excess growth hormone. The cure rate after acromegaly surgery is 85% for small pituitary tumors and 40-50% for large tumors. If the surgeon cannot remove the entire tumor, you may need further treatment with radiation therapy and/or medications to relieve symptoms and prevent complications of acromegaly.

What is the life expectancy for people with acromegaly?

Acromegaly is one of the rare disorders (endocrine diseases) typically diagnosed in middle-aged adults (in the fourth and fifth decades of life). Acromegaly develops when there is too much growth hormone in the body, usually due to a benign pituitary adenoma. There is nothing you can do to prevent acromegaly. It can be challenging to diagnose acromegaly because the symptoms develop slowly. Yet, if you do not get acromegaly treated, it can result in serious health problems that can lower your life expectancy. Complications of acromegaly can include high blood pressure, diabetes, heart disease, cardiomyopathy, arthritis, colon polyps, colon cancer, and other serious health conditions. However, with successful treatment, people with acromegaly can live normal lives and have a near-normal life expectancy.

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