acromegaly

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Acromegaly – what are the signs, symptoms , causes and treatments of Acromegaly?

Growth hormone complications

Growth hormone complications

Acromegaly is a condition in which the body produces too much growth hormone, leading to the excess growth of body tissues over time.

Typical features include:

  • abnormally large hands and feet
  • large, prominent facial features
  • an enlarged tongue
  • abnormally tall height (if it occurs before puberty)

Growth hormone is produced and released by the pituitary gland, a pea-sized gland just below the brain.

When growth hormone is released into the blood, it stimulates the liver to produce another hormone – insulin-like growth factor 1 (IGF-1) – which causes growth of muscle, bones and cartilage throughout the body.

This process is essential for growth and repair of body tissues.

What happens in people with acromegaly?

Acromegaly is caused by excessive production of growth hormone.


This usually occurs as the result of a benign (non-cancerous) brain tumour in the pituitary gland called an adenoma, but rare cases have been linked to tumours elsewhere in the body, such as in the lungs and pancreas.

Although acromegaly does very occasionally run in families, most adenomas are not inherited – they usually develop spontaneously as a result of a genetic change within a cell of the pituitary gland. This genetic change switches on a signal that tells cells in the pituitary gland to divide and secrete growth hormone.

The tumour almost never spreads to other parts of the body, but it may grow to more than 1cm in size and compress the surrounding nerves and normal pituitary tissue, which can affect the production of other hormones, such as thyroid hormones released from the thyroid gland.

Who is affected

It’s not clear exactly how many people are affected by acromegaly, although it’s been estimated that around 4 to 13 in every 100,000 people may have the condition.

This means there is likely to be between 2,500 and 8,300 people in the UK with the condition.

Acromegaly can affect people of any age, but it is rare in children. The average age at which people are diagnosed is around 40-45.

Problems caused by acromegaly

Acromegaly can cause a wide range of symptoms that tend to develop slowly over time.

Typical symptoms include:

Some of the above symptoms are the result of the tumour compressing nearby tissues – for example, headaches and vision problems may occur if the tumour squashes nearby nerves.

If you think you have acromegaly, see your GP straight away. Acromegaly can usually be successfully treated with brain surgery and medication, but early diagnosis and treatment is important to prevent the symptoms getting worse and to reduce your chance of getting complications.

Possible complications

If acromegaly is left untreated, you may be at risk of the following health problems:

Left untreated, these complications can become serious and fatal.

Diagnosing acromegaly

Blood tests

If your doctor suspects acromegaly from your symptoms, they will order blood tests to measure your levels of human growth hormone.

Levels of growth hormone naturally vary from minute to minute as it is released from the pituitary gland in spurts. Therefore to accurately diagnose acromegaly, growth hormone needs to be measured under conditions that normally suppress growth hormone secretion.

To ensure an accurate result, you may be referred to a hospital doctor for a glucose tolerance test. This involves testing your blood after drinking a solution or drink containing the sugar glucose.

In most people, drinking the glucose solution will suppress the release of growth hormone, but in people with acromegaly, the level of growth hormone in the blood will remain elevated.

Your doctor will also measure your level of IGF-1, which should increase with the level of growth hormone. An elevated IGF-1 level almost always indicates acromegaly.

Brain scans

You may then have a magnetic resonance imaging (MRI) scan of your brain to locate and define the size of the pituitary gland tumour causing your acromegaly.  A computerised tomography (CT) scan can be carried out if you are unable to have an MRI scan.

Treating acromegaly

Treatment aims to:

  • reduce excess growth hormone to normal levels
  • relieve the pressure the tumour is exerting on the surrounding structures
  • treat any hormone deficiencies
  • improve the symptoms of acromegaly

This is usually achieved through surgical removal of the tumour and medication.

Brain surgery

In most cases, surgery is recommended to remove the adenoma from your pituitary gland. This is effective in most people, although sometimes the tumour is too large to be removed completely.

Under a general anaesthetic, the surgeon will make an incision inside your nose or behind your upper lip to access the gland. An endoscope (a long, thin, flexible tube that has a light source and a video camera at one end) and surgical instruments are then passed through the incisions to remove the tumour.

Removing the tumour promptly relieves the pressure on the surrounding structures and leads to a rapid lowering of growth hormone levels. Facial appearance and swelling often improve within a few days.

Possible complications of surgery include damage to the healthy parts of the pituitary gland, leakage of cerebrospinal fluid (which surrounds and protects the brain), and  meningitis, though this is rare. Your surgeon will discuss these risks with you and answer any questions you have.

Radiotherapy

If surgery is not possible, or surgery and medication do not cure the condition, radiotherapy aimed at the adenoma may be an option.

This can eventually lead to a reduction in growth hormone levels, although it may not have a noticeable effect for several years and you may need to take medication in the meantime.

There are two main types of radiotherapy for acromegaly:

  • Stereotactic radiosurgery – where a high-dose beam of radiation is precisely aimed at the tumour, requiring you to wear a rigid head frame to keep your head still. This can sometimes be done in a single session.
  • Conventional radiotherapy – where the tumour is targeted with external beams. This can potentially damage the surrounding pituitary gland and brain tissue, so small doses of radiation are given over four to six weeks, giving normal tissue time to heal in between treatments.

Stereotactic radiosurgery is generally preferred to conventional radiotherapy because it minimises the risk of damage to nearby healthy tissue, although it is not always widely available.

Radiotherapy can have a number of side effects. For example, the treatment will often cause a gradual decline in the production of other hormones from your pituitary gland, so you’ll usually need to take hormone replacement therapy for the rest of your life. There’s also a risk it will impair fertility. Speak to your doctor about the risks involved.

Bowel cancer screening

There is some evidence acromegaly may increase your risk of bowel cancer, so guidelines recommend having a colonoscopy when you are diagnosed with the condition, and regular colonoscopy screening from the age of 40.

A colonoscopy is an examination of your entire large bowel using a type of endoscope called a colonoscope that is inserted into your bottom. See bowel cancer tests for more information about what a colonoscopy involves.

Outlook

Treatment is often effective at stopping the excessive production of growth hormone and improving problems caused by the condition. Treatment can also increase life expectancy to around that of someone without acromegaly.

Some treatments can take a long time to have a noticeable effect and you may need to take medication for a long period of time.

After treatment, you’ll need regular follow-up appointments with your specialist for the rest of your life. These will be used to monitor your pituitary function, check you are on the correct hormone replacement treatment, and to ensure the condition does not return.

Without treatment, acromegaly can cause long-term problems and may reduce life expectancy by a number of years.

[Original article on NHS Choices website]

Leave a comment Posted on A to Z of Medical Conditions, Skin conditions

Acanthosis nigricans – what are the signs and why we need to be aware of it?

Acanthosis nigricans

Acanthosis nigricans

It’s not a condition in itself, but can be a sign of an underlying health problem. These underlying conditions aren’t usually serious, although occasionally acanthosis nigricans can be sign of cancer.

Signs and symptoms

Dark, velvety patches.  If you have acanthosis nigricans, you’ll have thickened, brownish-grey or black patches of skin.

The patches will be dry and rough, feeling similar to velvet. They may also be itchy.

These patches may occur anywhere, but are usually seen around the neck, in the armpit, around the groin and sometimes in other skin folds. Occasionally, the skin over the joints of the fingers and toes may be affected, as well as the lips, palms of the hands and soles of the feet.

The patches usually develop slowly over time. Patches that grow and spread quickly are more likely to be associated with cancer. In these cases, the mouth, tongue, throat, nose and windpipe may also be affected.

Tiny growths on the skin

You may also have lots of tiny finger-like growths from the patches. This is known as papillomatosis.

There may also be skin tags around the affected area. These are small flesh-coloured or pigmented growths that hang off the skin and look a bit like warts.

When to see your GP

Acanthosis nigricans is usually harmless, but as it can be a sign of something serious it’s a good idea to see your GP if you think you have it. They may suspect acanthosis nigricans just by looking at your skin.

If the cause isn’t clear, you may have blood tests to check your blood sugar or hormone levels, and you might need additional tests such as an endoscopy or X-ray.

What causes acanthosis nigricans?

Acanthosis nigricans sometimes occurs in people who are otherwise in good health, particularly dark-skinned people of African descent.

However, in most cases it’s a sign of an underlying problem or condition such as obesity, diabetes or abnormal hormone levels. Some of the main causes of acanthosis nigricans are outlined below.

Obesity

Acanthosis nigricans is usually the result of obesity. This is known as obesity-associated acanthosis nigricans.

It occurs because obesity can cause insulin resistance (when the body is unable to properly use the hormone insulin), which may lead to high levels of insulin in the blood, affecting the skin cells.

Insulin resistance can also cause type 2 diabetes, so acanthosis nigricans can be an early sign that you have diabetes or are at risk of developing the condition.

Syndromes and hormone problems

Acanthosis nigricans is sometimes associated with an underlying syndrome or hormone problem, such as:

This type of acanthosis nigricans is known as syndromic acanthosis nigricans.

Genes

In rare cases, acanthosis nigricans can be caused by a faulty gene inherited directly from your parents. This is known as familial or benign genetic acanthosis nigricans.

This type is usually passed on in an autosomal dominant pattern, which means it can be passed on if only one of your parents carries the faulty gene.

Cancer

If the dark skin patches come on suddenly and spread quickly, it may be a sign you have cancer (usually stomach cancer). This is known as malignant acanthosis nigricans.

This is a rare condition that tends to affect middle-aged or elderly people, regardless of their weight or ethnic background.

The patches are more severe and the mouth, tongue and lips may also be affected. The skin may also become irritated and itchy.

How acanthosis nigricans is treated

Treatment for acanthosis nigricans aims to correct the underlying cause of your symptoms. This will usually cure the acanthosis nigricans or significantly improve the appearance of your skin.

Treatments that may be recommended include:

There’s no specific treatment to get rid of the patches, but a dermatologist (skin specialist) may be able to recommend treatments such as creams or tablets that may help improve the look of your skin.

Outlook

Most cases of acanthosis nigricans are harmless and not a sign of anything serious. The skin patches often fade with time as the underlying condition is treated.

If you have inherited acanthosis nigricans from your parents, your patches may gradually get bigger before staying the same or eventually fading on their own.

Only in cases where there is underlying cancer is the situation very serious. If the tumour is successfully treated, the condition may disappear, but unfortunately the types of cancer that cause acanthosis nigricans tend to spread quickly and a cure is often not possible.

[Original article on NHS Choices website]