Hypopituitarism happens when the pituitary gland fails to produce one or more hormones that are used to manage other glands in the body. (If the pituitary gland is failing to produce two or more hormones, it is called multiple pituitary hormone deficiency ; if it fails to produce any hormones, the condition is called panhypopituitarism .)
Symptoms of hypopituitarism will vary depending on which hormones are not being produced. Not everyone will have all the symptoms listed below. Among the possible symptoms are:
- Constipation
- Diabetes insipidus
- Difficulties conceiving a child
- Disturbed vision
- Dry skin
- Fatigue and a lack of energy
- Greater sensitivity to cold
- Headaches
- Impotence in males
- Irregular monthly periods (oligomenorrhoea) or no monthly periods (amenorrhoea) in women
- Low blood pressure and dizziness on standing
- Lower sex drive
- Muscle weakness
- Paleness
- Reduced body hair
- Weight gain
A variety of things can cause hypopituitarism, including:
- Accidents or injuries such as those associated with a fracture of the base of the skull
- Autoimmune disorders of the pituitary gland
- Complications of surgery or radiation
- Hemochromatosis, a disorder in which the blood has too much iron
- Infections such as meningitis, malarial or pituitary abscesses
- Interruption or total blocking of the blood supplying the pituitary gland with oxygen. This causes the tissues of the pituitary gland to die. This can be caused by pituitary failure or severe bleeding. It can also be caused by poor circulation due to diabetes or sickle cell anemia.
- Tumors of the hypothalamus gland
- Tumors of the pituitary gland such as adenomas or craniopharyngioms
Symptoms of hypopituitarism tend to be general and can resemble other conditions, including anorexia nervosa, chronic liver disease and hemachromatosis. An accurate diagnosis is essential before treatment is started.
If hypopituitarism is suspected, a doctor may order:
- Magnetic resonance imaging scans
- Blood tests to measure the amount of different hormones in the blood. In particular, tests should be done for thyroid-stimulating hormone (TSH) and ACTH. A lack of these hormones can be life-threatening. Prolactin levels may also be measured.
Once the missing hormone(s) have been identified, treatment consists of replacing the hormones produced by the target glands.
If the causes of the lack of hormones is a pituitary tumor, surgery may be needed as well. Some endocrinologists also prescribe drugs that work with dopamine (dopamine agonist drugs) such as bromocriptine, pergolide or cabergoline to treat prolactinomas. Radiation may also be used in addition to surgery and drug therapy.
