Overview
Hormone Excess and the Clinical Pattern
Acromegaly develops when a pituitary adenoma secretes growth hormone (GH) over years.
Acromegaly develops when a pituitary adenoma secretes growth hormone (GH) over years. GH stimulates production of insulin-like growth factor-1 (IGF-1), largely in the liver. IGF-1 drives the soft-tissue enlargement, bone remodelling, insulin resistance, and organ effects that give the disorder its characteristic pattern. In adults, the epiphyseal growth plates are closed. The patient does not become taller; instead, the hands, feet, jaw, tongue, and facial bones enlarge. A patient may describe rings that no longer fit, a larger shoe size, a changing bite, or dentures that have become uncomfortable. These gradual changes are easy to normalize until old photographs, prior shoe sizes, or previous clinical records make the progression visible. GH excess affects much more than appearance. Soft-tissue growth can narrow the upper airway and contribute to obstructive sleep apnoea. Insulin resistance raises the risk of diabetes. Cardiac muscle and vascular changes can produce hypertension, cardiomyopathy, dysrhythmias, and heart failure. Joint enlargement and nerve compression contribute to arthralgia and carpal tunnel symptoms. The tumour itself can also cause mass effects. Headache, reduced peripheral vision, diplopia, or other visual changes suggest...
