Pituitary infarction is the death of an area of tissue in the pituitary gland, a small gland joined to the hypothalamus (part of the brain). The pituitary produces many of the hormones that control essential body processes.
Causes, incidence, and risk factors:
Pituitary infarction is most commonly caused by bleeding due to a noncancerous tumor of the pituitary. When this bleeding occurs in a woman during or immediately after childbirth, it is called Sheehan syndrome .
Risk factors for pituitary infarction include:
- Bleeding disorders
- Head injury
- Radiation to the pituitary gland
- Use of a breathing machine
However, in most cases, the cause is not clear.
Pituitary infarction usually has a short period of symptoms (acute), but it can be life-threatening.
Symptoms usually include:
Less commonly, pituitary dysfunction may appear more slowly. In Sheehan syndrome, for example, the first symptom may be a failure to produce milk caused by a lack of the hormone prolactin.
Over time, problems with other pituitary hormones may develop, causing symptoms of the following conditions:
When the posterior pituitary is involved (rare), symptoms may include:
- Failure of the uterus to contract as needed to give birth to a baby (in women)
- Failure to produce breast milk (in women)
- Uncontrolled urination
Signs and tests:
Signs of acute pituitary infarction may include:
- Low blood pressure
- Visual field defects
Signs of chronic pituitary insufficiency include:
- Growth hormone deficiency
- Low blood pressure
- Poor response to stress and infection
Tests may include:
Blood tests will be done to check levels of:
Treatment for acute infarction may require surgery to relieve pressure on the pituitary and improve vision symptoms. Severe cases need emergency surgery.
Immediate treatment with adrenal replacement hormones (glucocorticoids) is essential. Other hormones will be replaced, including:
- Sex hormones (estrogen/testosterone)
- Thyroid hormone
Evidence is also growing for the need to replace growth hormone.
Acute pituitary infarction can be life-threatening. The outlook is good for people who have chronic deficiency that is diagnosed and treated.
Complications of untreated pituitary infarction can include:
If other missing hormones are not replaced, you may develop problems related to hypothyroidism and hypogonadism.
Calling your health care provider:
Call your health care provider if you have any symptoms of chronic pituitary insufficiency.
Go to the emergency room or call the local emergency number (such as 911) if you have symptoms of acute pituitary infarction, including:
- Eye weakness
- Low blood pressure (which can cause fainting)
Be especially concerned if you develop these symptoms and you have already been diagnosed with a pituitary tumor.
Melmed S, Kleinberg D. Anterior pituitary. In: Kronenberg HM, Melmed S, Polonsky KS, Larsen PR. Williams Textbook of Endocrinology. 11th ed. Philadelphia, PA: Saunders Elsevier; 2008:chap 8.