Acromegaly is caused by a noncancerous tumor in the pituitary gland, the “master gland”of the body, which controls growth, metabolism, and reproductive activity and sits in the sella turcica at the base of the brain. This tumor, called a pituitary adenoma, causes the pituitary gland to secrete excess growth hormone, which results in the tissue overgrowth.
体育投注正规网址Patients with this condition experience an increase in the size of their hands and feet, broadening of their fingers, and coarsening and broadening of their facial features. They may also experience headaches and can often suffer from diabetes, hypertension, and heart failure.
Only three or four patients per million individuals are diagnosed with the condition each year. Acromegaly develops gradually and typically is not diagnosed until several years—often, as many as seven—after excess growth hormone secretion has begun.
体育投注正规网址This condition usually occurs in patients without a family history of acromegaly. One should suspect the condition if the size of the patient’s shoes, rings, and gloves increase or if facial features start to coarsen and spaces between the upper front teeth widen.
The main symptoms are caused by abnormally high growth hormone and insulin growth factor (IGF-I) levels, and some are caused by the tumor itself. They include the following:
体育投注正规网址When growth hormone levels are not controlled, and diabetes and heart disease are present, the patient’s life expectancy may be reduced by as much as 10 years.
体育投注正规网址Because excess growth hormone levels stimulate increased production of IGF-1, acromegaly may be diagnosed either by measuring levels of insulin growth factor (IGF-I) or by measuring growth hormone levels directly. IGF-I measurement is the easiest detection method because it only requires a simple blood test and samples may be taken at any time of the day. Direct growth hormone measurement is more involved since it requires several recordings, both before and after the patient has ingested a glucose solution.
体育投注正规网址Once excessive growth hormone and IGF-I levels have been confirmed, magnetic resonance imaging (MRI) is used to examine the brain and determine whether a pituitary adenoma is present.
In treating acromegaly, the goal is to restore growth hormone and IGF-I in the blood to normal levels. If treatment succeeds, the soft tissue overgrowth will improve over several months and the risk of decreased life expectancy will return to where it was before the condition was diagnosed.
Surgical removal of the tumor is usually the first choice, but medications will be needed if surgery does not cure the condition. Potential treatments include synthetic analogues of the hormone somatostatin, dopamine agonists, and growth hormone antagonists. In some cases, radiation therapy may be required.