Question: What is Hyperprolactinemia?
Answer:
Pathophysiology
Prolactin is a hormone secreted by the pituitary gland in the brain. Its primary function is to enhance breast development and initiate lactation. Hyperprolactinemia occurs when this hormone is found in higher levels then normal in the blood. Typically, serum or blood levels are less then 20 ng/ml. Prolactin may be elevated for a few reasons. The first is a benign, pituitary tumor, known as a pituitary microadenoma. This tumor is not cancerous but can cause increased secretion of prolactin. Hyperprolactinemia can also be caused by an imbalance in the hormones which control the secretion. Hypothyroidism can also cause hyperprolactinemia. Certain medications, especially those that affect dopamine, usually found in anti-psychotics or antidepressants, can increase prolactin levels.Symptoms
Symptoms of hyperprolactinemia may be nonexistent, or women may notice the following:- infertility
- galactorrhea (abnormal lactation)
- infrequent or irregular periods
Diagnosis
Prolactin can be easily measured through a routine blood test. Because a number of factors can affect the blood values, one should avoid breast stimulation and intercourse the night before the test. If the blood test comes back elevated, the doctor may wish to repeat the test, this time after fasting for at least 8 hours. An MRI may be ordered to look for evidence of a pituitary growth.Treatment
Generally, two options are available for treating high prolactin levels. The first is medical care. The two most commonly prescribed medications are bromocriptine and dostinex. Bromocriptine is typically prescribed first, and can also be used to shrink a pituitary microadenoma in most cases. If the patient cannot tolerate bromocriptine, or if the physician feels that bromocriptine is not appropriate for the patient, doxtinex may be prescribed. Both of those drugs encourage the production of dopamine, which will inhibit prolactin secretion. Your doctor will probably want to periodically measure your prolactin levels to determine if therapy is effective. Medication can sometimes be stopped if prolactin levels return to and remain normal. Surgery can sometimes be indicated if the medication is not working or tolerated, or if a pituitary tumor is too large and not responding to medical therapy. Your doctor can determine what will work best for you.Source:
McCance, Kathryn L. and Huether, Sue E. Understanding Pathophysiology. Mosby. St. Louis MO, 2003. Pg 449-473.
