Overview of acromegaly
Acromegaly is a rare condition caused by excessive growth hormone secretion by a pituitary adenoma. Clinical features include:
- acral overgrowth (enlarged extremities [eg nose, ears, jaw, hands, feet])
- soft tissue changes
- increased sweating
- impaired glucose tolerance
- neuropathy
- arthritis
- hypertension
- cardiomyopathy
- sleep apnoea
- gigantism (children).
A diagnosis of acromegaly is confirmed by an increased serum growth hormone concentration that does not suppress during an oral glucose tolerance test, and an elevated plasma insulin-like growth factor 1 (IGF-1) concentration. An adenoma is usually identified with pituitary magnetic resonance imaging (MRI). Specialist advice is required to confirm the diagnosis and to guide management.
The aim of therapy for acromegaly is to reduce the plasma insulin-like growth factor 1 concentration to within the normal range for age and to lower the serum growth hormone concentration to less than 2.5 micrograms/L1. Some studies show a further benefit in reducing serum growth hormone concentration to less than 1 microgram/L.
Transsphenoidal surgery is usually first-line management.
If growth hormone excess persists after surgery, or if a patient is unsuitable for surgery, drug therapy can be used (see Drug therapy for acromegaly). Radiotherapy is an alternative option.
In addition to management of the adenoma, optimise management of cardiovascular disease risk factors. Good blood pressure control is particularly important. A baseline echocardiogram should be done routinely, as well as a sleep study to assess for sleep apnoea, if clinically indicated. A baseline colonoscopy is required, given the increased risk of colonic neoplasia (polyps and carcinoma).