Acromegaly and Gigantism Health Article

When to call the doctor

Because early diagnosis and treatment of acromegaly and gigantism can often lead to the avoidance of more serious symptoms, a healthcare professional should be contacted if a child develops any of the early symptoms of the disease, such as a marked increase in height or height that is excessive for his or her age.

Diagnosis

Because acromegaly produces slow changes, diagnosis is often significantly delayed. In fact, the characteristic coarsening of the facial features is often not recognized by family members, friends, or long-time family physicians. Often, the diagnosis is suspected by a new physician who sees the patient for the first time and is struck by the patient's characteristic facial appearance. Comparing old photographs from a number of different periods often increases suspicion of the disease. By contrast, the effects of gigantism are typically dramatic, with remarkable changes over a short period of time.

Because the quantity of GH produced varies widely under normal conditions, demonstrating high levels of GH in the blood is not sufficient to merit a diagnosis of acromegaly. Instead, laboratory tests measuring an increase of IGF-1 (three to ten times above the normal level) are useful. These results, however, must be carefully interpreted because normal laboratory values for IGF-1 vary when the patient is pregnant, is pubescent, is elderly, or is severely malnourished. Normal patients will show a decrease in GH production when given a large dose of sugar (glucose). Patients with acromegaly will not show this decrease and will often show an increase in GH production. Magnetic resonance imaging (MRI) is useful for viewing the pituitary gland and for identifying and locating an adenoma. When no adenoma can be located, the search for a GHRH-producing tumor in another location begins.

Treatment

The first step in treatment of acromegaly is removal of all or part of the pituitary adenoma. Removal usually requires surgery, usually performed by entering the skull through the nose. While this surgery can cause rapid improvement of many acromegaly symptoms, most patients will also require additional treatment with medication. Bromocriptine (Parlodel) is a medication that can be taken by mouth, while octreotide (Sandostatin) must be injected every eight hours. Both of these medications are helpful in reducing GH production but must often be taken for life and produce their own unique side effects.

Alternative treatment

Some patients who cannot undergo surgery are treated with radiation therapy to the pituitary in an attempt to shrink the adenoma. Radiating the pituitary may take up to ten years, however, and may also injure or destroy other normal parts of the pituitary.

Nutritional concerns

Individuals with acromegaly or gigantism who have diabetes or diabetes-like symptoms should maintain a diet that helps normalize blood sugar levels.

Prognosis

Without treatment, patients with acromegaly are likely to die early because of the disease's effects on the heart, lungs, brain, or due to the development of cancer in the large intestine. With treatment, however, a patient with acromegaly may be able to live a normal lifespan.

Prevention

The initial onset of acromegaly or gigantism cannot as of 2004 be prevented. Once a pituitary adenoma has been removed, radiotherapy and/or medication may be recommended to prevent a recurrence of the tumor.

Parental concerns

In the great majority of children of tall stature, genetics and nutrition are the cause of the greater-than-average height, and linear growth ceases with the end of puberty. In individuals with gigantism who are not treated, linear growth can continue unchecked for several decades. It is important that a child with the symptoms of gigantism be assessed medically so that treatment can be implemented and abnormal linear height as well as potentially serious symptoms such as heart disease or colon cancer be minimized or avoided.