Acromegaly Flashcards
Which gland produces growth hormone
Anterior pituitary gland
Most common cause of acromegaly
Pituitary adenoma
Cancers that cause acromegaly as a secondary effect
Lung cancer
Pancreatic cancer
cancers that secrete ectopic growth hormone releasing hormone(GHRH) or growth hormone
Presentation of a space occupying lesion
Headaches
Visual field defect (bitemporal hemianopia)
Features of acromegaly linked to 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
Features of acromegaly linked to organ dysfunction
Hypertrophic heart
Hypertension
Type 2 diabetes
Colorectal cancer
Which symptoms indicate raised growth hormone
Development of new skin tags
Profuse sweating
ix for acromegaly
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
Surgical intervention for pituitary adenoma
Trans-sphenoidal surgical removal of tumour
Medications which 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)
What is somatostatin
Somatostatin is known as “growth hormone inhibiting hormone”. It is normally secreted by the brain, gastro-intestinal tract and pancreas in response to complex triggers. One of the functions of somatostatin is to block GH release from the pituitary gland
Effect of dopamine on GH release
Dopamine also has an inhibitory effect on GH release, however not as potent as somatostatin.
Which syndrome is acromegaly commonly associated with
Carpal tunnel syndrome
