Hypopituitarism-Panhypopituitarism

The pituitary gland produces a number of hormones, which are released into the blood to control other glands in the body (thyroid, adrenal, ovary or testicles). If the pituitary is not producing one or more of these hormones, the condition is called hypopituitarism. If all the hormones produced by the anterior pituitary are decreased, the condition is called panhypopituitarism. Hypopituitarism is most often caused by large benign tumors of the pituitary gland, or of the brain in the region of the hypothalamus. Pituitary underactivity may be caused by the direct pressure of the tumor mass on the normal pituitary or by the effects of surgery or radiotherapy used to treat the pituitary tumors.

Less frequently, hypopituitarism can be caused by infections in or around the brain (such as meningitis) or by severe blood loss, by head injury, or by other rare diseases. Some of the clinical features that may be associated with hypopituitarism include excessive tiredness and decreased energy, irregular periods (oligomenorrhea) or loss of normal menstrual function (amenorrhea), impotence (in men), infertility, increased sensitivity to cold, constipation, dry skin, low blood pressure and lightheadedness upon standing (postural hypotension). Treatment of hypopituitarism consists of long-term hormone replacement therapy, since pituitary hormone deficits are rarely reversed after tumor removal.