American Medical Association Family Medical Guide - American Medical Association [601]
Diagnosis
A diagnosis of acromegaly is based on the symptoms and a physical examination. If your doctor suspects that you have acromegaly, he or she will probably refer you to an endocrinologist (a doctor who specializes in treating disorders of the endocrine system). The doctor may perform an X-ray of your skull to check for thickening or enlargement of the bones in the skull. He or she may also take X-rays of your hands to look for deformities in the finger bones.
The doctor will recommend a blood test to determine the level of growth hormone and insulinlike growth factor 1 (IGF-1) in the blood. High levels of these substances confirm the diagnosis. The doctor will then perform a CT scan (see page 112) or MRI (see page 113) of the pituitary gland to determine the location of the tumor and evaluate it.
Treatment
Treatment for acromegaly begins as soon as possible after the diagnosis is confirmed. Your doctor may prescribe a dopamine agonist such as bromocriptine or cabergoline to control the growth of the tumor. Dopamine agonists are drugs that imitate the actions of the chemical messenger dopamine and suppress the secretion of growth hormone by the pituitary gland. The doctor may prescribe the drug somatostatin, which also inhibits growth hormone and is often used to treat acromegaly. If these drugs are not effective, your doctor will probably recommend surgery or radiation therapy to remove or destroy the tumor.
Pituitary tumors can be selectively removed, leaving behind only healthy tissue. If most or all of your pituitary gland is removed or destroyed, you will need to take hormone replacement therapy for the rest of your life. Surgery or radiation treatments to remove or destroy the pituitary tumor may help improve vision problems by relieving pressure on the optic nerves. Although successful treatment stops progression of the disease, the changes in your bones and your appearance are permanent.
Hypopituitarism
In hypopituitarism, the anterior (front) lobe of the pituitary gland is underactive and does not produce adequate amounts of one or more pituitary hormones. Because the pituitary is the master gland that produces hormones that control other endocrine glands and many essential body processes, under-activity of the pituitary can result in a wide range of problems throughout the body.
Some common causes of hypopituitarism include severe head injuries, a pituitary tumor (see page 885) or a brain tumor (see page 682), treatment for a pituitary tumor or a brain tumor (such as surgery or radiation therapy), or an autoimmune disorder (in which the body’s immune system mistakenly attacks the pituitary gland). In some cases, the disorder develops for no obvious reason.
Symptoms
Because the pituitary gland stimulates several other endocrine glands, the symptoms of hypopituitarism are a combination of the symptoms of disorders related to the other affected glands. These disorders include hypothyroidism (see page 903), Addison’s disease (see page 899), infertility (see page 493), absence of menstrual periods (see page 846), and short stature.
Diagnosis
A diagnosis of hypopituitarism is based on the symptoms and a physical examination. Your doctor will probably perform blood and urine tests to measure the levels of pituitary hormones and evaluate the functioning of the anterior lobe of the pituitary gland. If the test results indicate that you have hypopituitarism, your doctor may recommend a CT scan (see page 112) or MRI (see page 113) to look for a pituitary tumor.
Treatment
The treatment for hypopituitarism involves taking oral and intravenous medications that replace the hormones of the pituitary and other affected endocrine glands.