Acromegaly

Definition

• Acromegaly is a rare disorder of excessive bone and soft tissue growth due to elevated levels of growth hormone. In young children, prior the completed fusion and growth of bones, excessive growth hormone can cause a similar condition called gigantism.

Causes

• In most cases, acromegaly is caused by over-secretion of growth hormone (GH) produced by a benign tumor of the pituitary gland. The pituitary gland is a small gland located at the base of the brain that produces many hormones. In a small number of cases, malignant tumors of other organs (pancreas, adrenal, lung) may be the source of excess GH.

Risk Factors

• Some rare cases of acromegaly are hereditary.
• The average age of diagnosis is 40-45 years old.

Symptoms

• Symptoms usually develop very slowly over time.
• Acromegaly can cause serious complications and premature death if not treated.
• In children, excess GH production causes elongation of the bones and associated soft tissue swelling. If not treated, children with this disorder can grow ta height of 7-8 feet.
• Symptoms and complications in adults may include the following:
  • Abnormally large growth and deformity of the:
    • Hands (rings nlonger fit)
    • Feet (need a bigger size shoe)
    • Face (protrusion of brow and lower jaw)
    • Jaw (teeth dnot line up correctly when the mouth is closed)
    • Lips
    • Tongue
  • Carpal tunnel syndrome
  • Skin changes, such as:
    • Thickened, oily, and sometimes darkened skin
    • Severe acne
    • Excessive sweating and offensive body order due tenlargement of the sweat glands
  • Deepening voice due tenlarged sinuses, vocal cords, and soft tissues of the throat
  • Fatigue and weakness in legs and arms
  • Sleep apnea
  • Arthritis and other joint problems especially in the jaw
  • Hypothyroidism
  • Enlargement of the liver, kidneys, spleen, heart, and/or other internal organs, which can lead to:
    • Diabetes
    • High blood pressure
    • Cardiovascular disease
• In women:
  • Irregular menstrual cycles
  • Galactorrhea (abnormal production of breast milk) in 50% of cases
• In men:
  • In about 50% of cases, impotence

Diagnosis

• Blood tests will be done tmeasure the level of insulin-like growth factor (IGF-I), growth hormone releasing hormone (GHRH) , and other pituitary hormones.
• A glucose tolerance test may alsbe given tsee if the GH level drops—it will not drop in cases of acromegaly.
• If these tests confirm acromegaly, the following may be done tlocate the tumor that is causing the disorder:
• Head CT Scan—a type of x-ray that uses a computer tmake pictures of the inside of the brain and surrounding structures
• MRI Scan

Nursing Diagnosis

Treatment

• Reduce production of GH to normal levels
• Stop and reverse the symptoms caused by over-secretion of GH
• Correct other endocrine abnormalities (thyroid, adrenal, sex organs)
• Reduce the tumor size

Treatment may include:

Surgery

• Surgical removal of the pituitary tumor, or other tumor, that is believed to be causing acromegaly may be done. In most cases, this is the preferred treatment.

Radiosurgery

• Radiosurgery is the use of highly focused external beams of radiation tshrink the tumor. It is used most often in patients whdnot respond tconventional surgery or medications.

Radiation Therapy

• Radiation therapy is used in combination with either medical and/or surgical treatment.

Medication

Drugs may be given treduce the level of GH secretion from the pituitary gland. These include:

• Cabergoline (Dostinex)—given orally
• Pergolide (Permax)—given orally
• Bromocriptine (Parlodel)—may be given before surgery tshrink tumor
• Octreotide (Sandostatin)—given by injections
• Pegvisomant—given by injections for patients not responding tother forms of treatment

Medications must often be combined with other therapies ttreat larger tumors affecting surrounding structures.

Prevention

• There are guidelines for preventing acromegaly.
• Early diagnosis and treatment, however, will help prevent serious complications, some of which are irreversible.