HORMONAL PROBLEMS

Because of the complexity of the endocrine system, many problems, great or small, can result from a malfunction.

Pituitary gland disorders.Growth hormone (GH) stimulates growth in most tissues and is one of the major regulators of metabolism. Several pathological conditions are associated with abnormal GH secretion. In general, the causes for hypersecretion or hyposecretion of GH involve tumors in the hypothalamus or the pituitary, the synthesis of structurally abnormal GH, the inability of the liver to produce somatomedins, or the lack of receptor molecules in the target cells. Chronic hyposecretion of GH in infants and children leads to dwarfism in which the stature is short because of delayed bone growth; however, the bones usually have a normal shape. Other symptoms that result from the lack of GH include mild obesity and retarded development of the adult reproductive functions. Chronic hypersecretion of GH leads to one of two conditions (giantism and acromegaly). Treatment for chronic hypersecretion of GH often involves surgical removal or irradiation of a GH-producing tumor.

The inability to secrete antidiuretic hormone (ADH) leads to the production of a large volume of dilute urine. This condition is called diabetes insipidus.

The most common thyroid disorders are hyperthyroidism and hypothyroidism. Hyperthyroidism occurs when the thyroid gland produces excessive amounts of thyroid hormone. The signs of this disorder are the following: weight loss despite increased appetite, increased heart rate and blood pressure, nervousness, swelling at the base of the neck (goiter), increases in the frequency of bowel movements, sometimes diarrhea, and muscle weakness. Three types of treatment are available: a liquid form of radioactive iodine, an antithyroid medication, and surgery. An underactive thyroid gland causes hypothyroidism. This disorder can occur in either sex and at any age. However middle-aged women are most commonly affected. The key treatment is daily consumption of thyroid hormone. Physicians generally prescribe a synthetic thyroxine. The individual must continue this treatment for the rest of his or her life.

The hormones of the adrenalglands affect virtually every system in the body to some degree. Their effects are complex. Disturbances can occur in this intricate system, leading to such disorders as Addison's disease, aldosteronoma, congenital adrenal hyperplasia and others. Symptoms result from the release of large amounts of epinephrine and norepinephrine and include weight loss, darkening of the skin, sweating, nervousness, and tachycardia. Treatment requires daily doses of steroid tablets and salt supplements.

Sometimes the pancreas' balanced system of control fails. The amount of glucose in the bloodstream increases. The result is hyperglycemia. This condition is easily diagnosed by measuring the concentration of glucose in the blood. If it is high enough, some glucose will spill into the urine, where it can be detected easily. When the body's cells are unable to use the glucose in the bloodstream because of a lack of insulin activity (absence of enough hormone or resistance to the hormone), diabetes mellitus results. It is very serious disease but modern medications have made possible the effective management of diabetes mellitus.