Acromegaly

Question 1

What is acromegaly called in adults and children and when is it before or after?

Answer 1

Acromegaly in adults (epiphyseal fusion)
Gigantism in children (before epiphyseal fusion)

Question 2

Definition of acromegaly?

Answer 2

Release of excess growth hormone (GH) causing overgrowth of all systems

Question 3

Causes of acromegaly

Answer 3

Functional pituitary adenoma (main cause - 99%)
Malignancy secreting ectopic GH (eg. Lung cancer)

Question 4

What does IGF-1 stand for?

Answer 4

Insulin like growth factor

Question 5

Pathology of acromegaly

Answer 5

GHRH —> GH (from somatotrophs) —> IGF-1
In acromegaly, high IGF-1 (produced by liver)

Question 6

Signs and symptoms of acromegaly

Answer 6

Large hands and feet
box jaw
vision defect (bitemporal hemianopia)
sleep apnoea (increased larynx soft tissue)
profuse sweating,
lower pitch of voice,
large interdental gaps + Macroglossia (enlarged tongue),
carpel tunnel syndrome,
IGT (risk of T2DM),
back pain

Question 7

How to diagnose acromegaly?

Answer 7

1st line screening - IGF-1 test = serum level high

Gold standard- impaired glucose tolerance test (OGTT) - glucose suppresses GH

Other: random serum GH - high, MRI of pituitary fossa

Question 8

Treatment of acromegaly

Answer 8

1. Transsphenoidal surgery (if cause is adenoma)
2. Somatostatin analogues (ocreotide)
3. GH receptor antagonist (pegvisomant)
4. Dopamine agonist (bromocriptive or cabergoline)

Question 9

Complications of acromegaly

Answer 9

T2DM, sleep apnoea, erectile dysfunction