Expansion
Acral and soft tissue overgrowth with metabolic and mass effects
Expansion
Local (pituitary mass)
- Bitemporal hemianopia from chiasmal compression
- Headache
- Hypopituitarism, and hyperprolactinaemia from stalk compression
Growth hormone excess
- Enlarged hands and feet, coarse facial features, prognathism, interdental separation, macroglossia
- Carpal tunnel syndrome and other entrapment neuropathies
- Sweating, oily skin, skin tags
- Deep voice, obstructive sleep apnoea
- Arthropathy and proximal myopathy
Metabolic and systemic
- Insulin resistance and diabetes, since growth hormone is an insulin antagonist
- Hypertension and cardiomyopathy, the main causes of excess mortality
- Increased risk of colonic polyps and colorectal cancer, so surveillance colonoscopy is offered
Investigation: raised IGF-1, failure to suppress growth hormone during an oral glucose tolerance test, then pituitary MRI.
Treatment is transsphenoidal surgery first line, with somatostatin analogues, the growth hormone receptor antagonist pegvisomant, dopamine agonists and radiotherapy as adjuncts.