Acromegaly

– Growth hormone (GH) excess after Epiphysis fusion . Majority are due to somatotroph-adenonma (hormone secreting) pituitary tumour).

Clinical features

• 1/3 – show clinical features and Visual field defects
• Headache and sleep apnoea are common

Diagnosis

• GH <0.4 ng/ml (normal adults)
• • Glucose tolerance test (GTT)  – diagnostic (no suppression of GH)
• IGF-1 – raised in acromegaly – plasma value shows 24hr mean
• Vision field – bitemporal hemianopia
• MRI / pituitary function

Treatment

• Untreated – death from heart failure, coronary artery disease, neoplasms
• Need to decrease GH below 0.25ng/ml (considered safe)
• Trans-sphenoidal surgery – better for microadenoma
• Radiotherapy – if surgery isn’t curative + somatostatin analogue (octreotide -negative feedback on growth hormone)
• D₂ agonist – bromocriptine [10-60mg], carbergoline [0.5mg]
• GH antag – pegvisomant (injection)