Acromegaly Flashcards
1
Q
What does a pituitary adenoma make?
A
High GH, High IGF-1
2
Q
What is the most common cause of acromegaly?
A
Pituitary adenoma (of somatotrophs)
3
Q
What are features of acromegaly?
A
- Coarse facial features
- Prognathism & large tongue
- Spade-like hands & large feet
- Excessive sweating
- Organomegaly
- Bitemporal hemianopia
4
Q
What happens in gigantism?
A
growth of long bones
5
Q
What is management of acromegaly?
A
- Trans-sphenoidal surgery
* Radiotherapy
6
Q
What is the medicinal management of acromegaly?
A
- Somatostatin analogues
- Dopamine receptor agonists
- GH-receptor antagonists
7
Q
What investigations are done in acromegaly?
A
- OGTT
- Plasma IGF-1
- MRI
8
Q
How does OGTT work?
A
- increased GH in severe acromegaly
- normally when glucose is given, somatostatin activity in the hypothalamus increases so less GH
- some acromegaly patients, GH excess drives further GH via activation of GIP receptors present on somatotrophs in anterior pituitary.
9
Q
What are possible complications of acromegaly?
A
- Carpal tunnel syndrome
- Hypertension
- Diabetes mellitus
- Cardiomyopathy
- Colorectal cancer
10
Q
What does the HPS axis involve?
A
GHRH from anterior pituitary somatorophs relase GH
11
Q
What does GH do?
A
- Increase blood glucose
- Increase insulin resistance
- Increase muscle growth
- Increase bone thickness
12
Q
What organs does GH act on?
A
on liver, muscle, bone and kidneys to produce IGF-1
13
Q
What does IGF-1 do?
A
- Increases cell division
- Decreases apoptosis
- Increases cellular metabolism
14
Q
What is IGF-1 also known as?
A
somatomedins
15
Q
What does somatostatin do?
A
inhibits anterior pituitary (regulates)
