Acromegaly

Question 1

Definition

Answer 1

Chronic, progressive, multi-systemic excessive secretion of growth hormone
Most commonly due to pituitary somatotroph adenoma

Question 2

What are 5% of cases associated with

Answer 2

MEN 1

Question 3

Pathogenesis

Answer 3

+growth or bone and soft tissue

GH->+IGF-1

Question 4

Key diagnostic factors

Answer 4

Coarsening of facial features
Soft tissue/skin changes
Carpal tunnel syndrome
Acroparasthesia
Joint pain/dysfunction
Snoring
Altered sexual fuunction
Hx/FHx of inherited syndrome

Question 5

Signs of acromegaly

Answer 5

\+growth of hands
coarse facial
\+supra orbital ridges
Macroglossia
widely spaced teeth
puffy lips/lids
skin darkening
acanthosis nigricans
laryngeal dyspnea
OSA
Goitre
proximal weakness and arthopathy
carpal tunnel
mass effects->headache, VFDs, cranial nerve palsies, features of hypopituitarism

CVS: HTN, hypertrophic cardiomyopathy, arrythmias
Metabolic->glucose intolerance

Effects of prolactin co-secretion->-ve libido, infertility, amenorrhea/oligomenorrhea, galactorrhea, erectile dysfunction

Question 6

Complications

Answer 6

CCF
Ketoacidosis
Glucose intolerance
\+BP
Hypertrophic cardiomyopathy
\+colon cancer risk

Question 7

Investigations

Answer 7

\+Glucose->OGTT
\+Calcium
\+Phosphate
Serum IGF-1
Random serum GH >0.4 microG/L
ECG/Echo

Tests to consider:
Pituitary MRI/CT
GHRH->elevated in ectopic
Chest/abdominal CT-tumor localisation
Octreoscan
Plasma cortisol-may be low
Prolactin- often elevated
TSH and free T4- may be abnormal
Estradiol or testosterone- often reduced
Visual field testing

Question 8

Management

Answer 8

enclosed pituitary tumour
1st line: transsphenoidal surgery
2nd line: somatostatin analogue (SSA)->octreotide: long acting depot every 4 weeks for 3 months
adjunct: dopamine agonist->cabergoline
3rd line: growth hormone-receptor antagonist (GHRA)->pegvisomant
4th line: radiotherapy: conventional or stereotactic

unresectable pituitary tumour (with neural or vascular impingement/invasion)
1st line: somatostatin analogue (SSA)
adjunct: dopamine agonist
adjunct: debulking surgery
2nd line: growth hormone-receptor antagonist (GHRA)
3rd line: radiotherapy: conventional or stereotactic

non-pituitary adenoma aetiology
1st line: medical and surgical interventions

Ongoing
pituitary adenoma progression or recurrence
1st line: repeat surgery

Question 9

Side effects of somatostatin analogues

Answer 9

Pain at injection site

GIT: abdominal cramps, flatulence, loose stools, gall stones, impaired glucose tolerance

Question 10

Follow up

Answer 10

Yearly GH, IGF-1, OGTT, visual fields, vascular assessment, BMI, photos