Acromegaly Patient Information Fact Sheet

What is acromegaly?
Acromegaly is a disease of the pituitary gland (a small gland found at the base of your brain) that causes too much growth hormone (somatotropin) to be produced. This can occur if there is a disorder of the gland, such as a tumor. If a pituitary tumor occurs during childhood, it will cause gigantism because of rapid overgrowth of the bones of the arms and legs. If a pituitary tumor occurs after adolescence when the bones have stopped growing, it will cause acromegaly, resulting in enlargement of the head, feet and hands. If childhood gigantism is not treated, it will lead to acromegaly in later life.

Acromegaly is a very rare disease, with around 117 new cases per million per year. It usually develops in adults between the ages of 30 and 50.

What are the symptoms of acromegaly?
Sometimes, the first symptoms of acromegaly are tiredness and sleep disturbance. There is no increase in height in acromegaly, but thickening of the bones causes enlargement of the head, and in particular the lower jaw. In addition, the hands and feet widen and the fingers become much broader. Increased cartilage growth can increase the size of the nose and ears, while increased cartilage growth in the chest can result in an increased chest girth. Overgrowth of the larynx (voice box) may cause the voice to deepen and the skin may become thicker and coarser in texture. Perspiration may also be a problem, especially in women, and the skin may become oily. Growth of a pituitary tumor increases pressure within the skull and can cause headaches and visual disturbances. In addition, around a third of people with acromegaly go on to develop diabetes.

The pituitary gland produces other hormones besides growth hormone, including thyroid stimulating hormone (TSH), follicle stimulating hormone (FSH) and adrenocorticotropic hormone (ACTH). In people with acromegaly, the rest of the pituitary gland may become underactive, resulting in decreased levels of these hormones. This can cause symptoms such as diminished sexual function, loss of menstrual periods (amenorrhea), and symptoms of an underactive thyroid gland. A pituitary problem diagnosed based upon these symptoms before the symptoms of acromegaly are apparent.