- acromegaly
-
—acromegalic /ak'roh meuh gal"ik/, adj./ak'reuh meg"euh lee/, n. Pathol.a chronic disease characterized by enlargement of the bones of the head, the soft parts of the feet and hands, and sometimes other structures, due to excessive secretion of growth hormone by the pituitary gland.[1885-90; < F acromégalie < NL acromegalia. See ACRO-, -MEGALY]
* * *
Growth and metabolic disorder in which the skeletal extremities enlarge when a pituitary gland tumor causes overproduction of growth hormone after maturity.It is often associated with pituitary gigantism. Acromegaly is characterized by gradual enlargement of hands and feet, exaggeration of facial features, skin thickening, and enlargement of most internal organs, along with headaches, excessive sweating, and high blood pressure. Acromegalic individuals are likely to develop congestive heart failure, muscle weakness, joint pain, osteoporosis, and often diabetes mellitus and visual problems, including blindness. If treatment with surgery and/or radiation fails, then hormone therapy is used. Treatment can cause hormone deficiency, necessitating hormone replacement therapy; spontaneous events may also cause hormone deficiency.* * *
growth and metabolic disorder characterized by enlargement of the skeletal (skeletal system, human) extremities. It is the result of overproduction of pituitary growth hormone (somatotropin) after maturity, caused by a tumour of the pituitary gland. Acromegaly is often associated with the abnormal growth in stature known as pituitary gigantism (see gigantism).The onset of acromegaly is gradual. Hands and feet become enlarged; facial features are exaggerated as the jaw lengthens and the nose and forehead grow thicker; the skin thickens; and most internal organs enlarge. Headache, excessive sweating, muscle weakness, and high blood pressure are other manifestations.Acromegalic subjects may develop congestive heart failure, particularly when blood pressure becomes high. At times, excessive overgrowth of bone and cartilage involves the joints and causes pain. The bones may become thin and porous—a condition known as osteoporosis. diabetes mellitus appears in 20 to 40 percent of acromegalic subjects because excess growth hormone blocks the action of insulin. If the pituitary tumour enlarges, it can cause visual-field defects, blindness or paralysis of the eye muscles, and can injure the posterior pituitary gland or the hypothalamus. Also, hemorrhage into the tumour can cause sudden loss of vision.Acromegaly may be treated by surgical removal of the pituitary tumour or destruction of it by X-ray irradiation or liquid nitrogen. Rarely, the pituitary tumour will cease to secrete growth hormone because of a spontaneous hemorrhage or a blockage of the blood supply. Decreases in acromegalic manifestations and amelioration of diabetes mellitus have followed therapy with female hormones—estrogen or medroxyprogesterone—which reduce the secretion of growth hormone. For those treated by pituitary surgery, irradiation, or other measures and for those who spontaneously develop deficits of gonadal, thyroidal, or adrenocortical hormones, replacement-hormone therapy is necessary.* * *
Universalium. 2010.
