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 into a benign tumor of the pituitary, which kills an area of tissue in the pituitary gland. When bleeding occurs during or immediately after childbirth, it is called Sheehan's syndrome . Risk factors for pituitary infarction include diabetes , bleeding disorders, head trauma, pituitary radiation, and use of a breathing machine. However, in most cases, the cause is not clear. Pituitary infarction is usually acute (short period of symptoms) and can be life-threatening.
Signs and tests
Signs of acute infarction may include ophthalmoplegia, visual field defects, and hypotension (low blood pressure). Signs of chronic pituitary insufficiency include:
hypogonadism sparse axillary and pubic hair loss of sexual function cessation of mentrual cycle in women erectile dyfunction in men hypothyroidism dry hair and skin puffy face delayed reflexes hypoadrenalism hypotension poor response to stress and infection hypoprolactinemia: lack of lactation growth hormone deficiency : loss of muscle mass general: fine, pale, wrinkled skin Tests may include:
test for abnormal visual fields MRI or CT scan showing hemorrhage
low estradiol/testosterone with low FSH and LH low free T4 and TSH low cortisol and ACTH; rise of cortisol may be absent with Cortrosyn stimulation low GH and somatomedin C (IGF-1) low prolactin
elevated LDL cholesterol low bone density
Treatment
Treatment for acute infarction may require surgery to decompress the area of the pituitary and improve visual symptoms. Severe cases constitute a surgical emergency. Immediate treatment with adrenal replacement hormones (glucocorticoids) is essential. Replacement of other missing hormones is also required, including sex hormones (estrogen/testosterone) and thyroid hormone. Evidence is growing for the need for growth hormone replacement.
Expectations (prognosis)
Acute pituitary infarction is a potentially life-threatening event. Prognosis for chronic deficiency (which is detected and treated) is good.
Complications
Complications of untreated pituitary infarction can include visual loss and adrenal crisis. If other deficient hormones are not replaced, problems related to hypothyroidism and hypogonadism may develop.
Calling your health care provider
Call your health care provider if you have any signs or 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 headache, eye weakness, low blood pressure (which can cause fainting), nausea, and vomiting. Patients with a diagnosed pituitary tumor should have a heightened level of suspicion if these symptoms arise.