acromegaly

Question 1

definition

Answer 1

A rare, chronic disease caused by excessive secretion of growth hormone (GH), usually due to a pituitary somatotroph adenoma. It is associated with increased morbidity and premature mortality if not appropriately treated.

The diagnosis is often delayed. Early recognition and appropriate treatment are crucial for reducing the potentially debilitating complications of the disease.

Must be screened for in the presence of pituitary adenoma, profuse sweating, acral growth, coarsening of facial features, and when suspected in conjunction with commonly associated conditions, such as carpal tunnel syndrome, arthralgia, glucose intolerance or diabetes, amenorrhoea, hypertension, and sleep apnoea.

Modern surgical and pharmacological modalities are associated with improved outcomes. Normalisation of plasma insulin-like growth factor 1 (IGF-1) and a decrease of plasma GH to below 1 microgram/L (1 nanogram/mL) bring the mortality rate to normal.

Monitoring and treatment of the comorbidities associated with acromegaly are essential for improving the quality of life of patients.

Question 2

symptoms/signs

Answer 2

• coarsening of facial features
• sweating
• soft tissue and skin changes
• organomegaly (enlarged goitre, prostate)
• headaches
• hypertension
• arrhythmias
• diabetes mellitus -> polyuria, polydipsia
• fatigue
• increased appetite
• carpal tunnel
• joint pain and dysfunction
• snoring
• alterations in sexual function (hyperprolactinaemia from prolactin cosecretion by the adenoma)

Question 3

investigations

Answer 3

1st investigations:
- IGF-1
- oral glucose tolerance test
random serum growth hormone

others:
- pituitary MRI/CT
- GHRH
- chest and/or abdo CT (look for ectopic source of GH)
other baseline tests for acromegaly:
- cortisol
- prolactin
- TSH, T4
- estradiol or testosterone
- visual field testing (checking for compression of optic chiasm)

Question 4

treatment

Answer 4

for enclosed pituitary tumour:
1. transsphenoidal surgery 
2. somatostatin analogue (octreotide)
\++ dopamine agonist (cabergoline)
3. GH receptor antagonist (pegvisomant)
4. radiotherapy 

for non resectable pituitary tumour:
1. octreotide 
\++ dopamine agonist 
\++ tumour debulking 
2. pegvisomant 
3. radiotherapy

Question 5

complications

Answer 5

• cardiac complications
• sleep apnoea
• hypertension
• impaired glucose tolerance and diabetes mellitus
• osteoarticular complications (due to articular cartilage hypetrophy etc.)
• carpal tunnel