Acromegaly

Question 1

what is the def of acromegaly

Answer 1

constellation of signs & symptoms caused by hypersecretion of GH inadults

Question 2

what does excess GH in children cause

Answer 2

gigantism

Question 3

what is the aetiology of acromegaly

Answer 3

common: GH-secreting pituitary adenoma
rare: excess GHRH causing somatotroph hyperplasia from hypothalamic ganglioneuroma
bronchial carcinoid/pancreatic tumours

Question 4

what is the epi of acromegaly

Answer 4

rare

middle age

Question 5

what is the history associated with acromegaly

Answer 5

insidious onset
may complain of rings/shoes becoming tight
sweating, headache, carpal tunnel syndrome
symptoms of hypopituitarism (hypogonadism/thyroidism/adrenalism)
visual disturbances by optic chiasm compression
hyperprolactinaemia (irregular periods, low libido, impotence)

Question 6

what examination findings are associated with acromegaly

Answer 6

enlarged hands and feet (plus signs of carpal tunnel syndrome)
prominent eyebrow ridge& cheeks & nasolabial folds, broad nose bridge, thick lips, prognathism
husky resonant voice (thickening of vocal cords)
bitemporal superior quadrantanopia progressing to bitemporal hemianopia (optic chiasm compression by pituitary tumour)

Question 7

what investigations would be performed in suspected acromegaly

Answer 7

serum IGF-1
-GH stimulates liver IGF-1 secretion
oral glucose tolerance test
-failure of suppression of GH after 75g oral glucose
pituitary function tests
-9am cortisol, free T4 & TSH, LH, FSH, testosterone (males) & prolactin (test for hypopituitarism) 
MRI brain
-for pituitary tumour

Question 8

when would an oral glucose tolerance test produce false positive results

Answer 8

anorexia nervosa
Wilson’s disease
opiate addiction

Question 9

what would be the management in acromegaly

Answer 9

surgical
-removal of pituitary tumour is only curative treatment
radiotherapy
-adjunctive treatment to surgery
medical
-if surgery contra-indicated
-SC somatostatin analogues (octreotide, lanreotide)
-oral dopamine agonists (bromocriptine, cabergoline)
-GH antagonist (pegvisomant)

Question 10

what complications are associated with acromegaly

Answer 10

CVS
-cardiomyopathy, HTN
resp
-obstructive sleep apnoea
GI
-colonic polyps
reproductive
-hyperprolactinaemia (30%)
metabolic
-hypercalcaemia/phosphataemia, DM
psychological
-depression, psychosis (dopamine agonist therapy)

Question 11

what is the prognosis of acromegaly

Answer 11

good with early diagnosis & treatment

physical changes are irreversible