Acromegaly

Question 1

What is acromegaly?

Causes

Answer 1

In acromegaly there is excess growth hormone secondary to a pituitary adenoma

Other causes:
- pancreatic cancer secretes ectopic growth hormone releasing hormone (GHRH) or growth hormone

Question 2

Clinical Features

Answer 2

Space Occupying Lesion

• Headaches
• Visual field defect (“bitemporal hemianopia”)
• Overgrowth of tissues
• Prominent forehead and brow (“frontal bossing”)
• Large nose
• Large tongue (“macroglossia”)
• Large hands and feet
• Large protruding jaw (”prognathism”)
• Arthritis from imbalanced growth of joints

GH can cause organ dysfunction

• Hypertrophic heart
• Hypertension
• Type 2 diabetes
• Colorectal cancer

Symptoms suggesting active raised growth hormone

• Development of new skin tags
• Profuse sweating
• Hypertension

Question 3

Diagnosis

Answer 3

Insulin-like Growth Factor 1 (IGF-1) is the initial screening test (raised)

Oral glucose tolerance test whilst measuring growth hormone (high glucose normally suppresses growth hormone)

MRI brain for the pituitary tumour

Refer to ophthalmology for formal visual field testing

Pituitary Screen

Question 4

Treatment

Surgery

Answer 4

Trans-sphenoidal (through the nose and sphenoid bone) surgical removal of the pituitary tumour is the definitive treatment of acromegaly secondary to pituitary adenomas.

Question 5

Treatment

Medical

Answer 5

Where acromegaly is caused by ectopic hormones from a pancreatic or lung cancer, surgical removal of these cancers is the treatment.

There are medication that can be used to block growth hormone

• Pegvisomant (GH antagonist given subcutaneously and daily)
• Somatostatin analogues to block GH release (e.g. ocreotide)
• Dopamine agonists to block GH release (e.g. bromocriptine)