- What is Acromegaly
- Statistics on Acromegaly
- Risk Factors for Acromegaly
- Progression of Acromegaly
- Symptoms of Acromegaly
- Clinical Examination of Acromegaly
- Prognosis of Acromegaly
- How is Acromegaly Treated?
- Acromegaly References
What is Acromegaly
Acromegaly is a chronic metabolic disorder caused by the presence of too much growth hormone – GH and IGF-I hypersecretion. Growth hormone is a hormone secreted by the pituitary gland in response to GHRH secretion from the hypothalamus, and in excess it results in gradual enlargement of body tissues including the bones of the face, jaw, hands, feet, and skull.
Statistics on Acromegaly
- Incidence is 5.3 per 100000 per year;
- Males and females are affected equally;
- Highest incidence in middle age (4th and 5th decades);
- It is estimated that six years elapse between the onset of symptoms and the diagnosis.
Risk Factors for Acromegaly
The cause is usually a benign pituitary tumour (pituitary adenoma). Hyperplasia from excessive GHRH secretion from the hypothalamus is the other main cause but that is rare. There are no known risk factors for acromegaly other than a prior history of a pituitary tumor.
Progression of Acromegaly
The life expectancy of a patient with untreated acromegaly is 50 years, most due to a hypertrophic cardiomyopathy and malignant ventricular arrhythmias. Osteoporosis and fractures are frequent complications. Although glucose intolerance is common very few develop ketoacidosis or other significant complications of diabetes mellitus. The tumour may compromise visual fields.
When it is adequately treated, life expectancy returns to normal and the other complications remit.
Prognosis of Acromegaly
Indicators of disease severity:
- Excessive sweating;
- Skin tags;
- Increased loss of visual fields.
How is Acromegaly Treated?
Treatment is indicated in all except elderly or those with minmal abnormalities (untreated leads to markedly reduced survival). The Aim is to reduce mean growth hormone levels to below 5 mU/l.
Surger is the treatment of choice in suitable cases – transsphenoidal or transfrontal if the tumour is large. Surgery is often combined with radiotherapy because excision is rarely complete with large tumours.
External beam radiotherapy
Normally used after pituitary surgery fails to normalize growth hormone levels rather than as primary therapy. May take 1-10 years to be effective when used alone.
Subcutaneous octreotide or lanreotide (somatostatin analogues). Treatments of choice in resistant cases. Given to shrink tumours before definitve treatment or to control symptoms. Bromocriptine is usually reserved for eldery and frail people.
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