Hyperprolactinemia is an excessive secretion of prolactin, a hormone secreted by the pituitary gland. A rate above 20 ng / ml in the morning on an empty stomach two successive samples is considered pathological. The pituitary gland, which lies in a bony cavity at the base of the brain produces and releases, among others, prolactin, known for its role in lactation. Produced in excessive amounts, this hormone can see its effects exaggerated. Impacts differ by sex.
In women, there are menstrual disorders and, sometimes, the complete disappearance of ovulation. Hyperprolactinemia is one of the most common hormonal disorders responsible for female infertility. Hyperprolactinemia may also be responsible for infertility. The men suffer from erectile dysfunction accompanied by a reduced sex drive. In both sexes, a flow of milk (or galactorrhea), without or after stimulation of the nipple, is possible.
In some cases, we do not find cause. We then say that is idiopathic hyperprolactinemia.
Prolactin is the hormone of lactation, it causes the output of milk after birth and is responsible for the growth of mammary glands. Excess prolactin in the blood leads to an exaggeration of its effects. We observe the appearance of breasts (gynecomastia) in men and flow of milk from the nipples as in women than in men.
Moreover, increased levels of prolactin in the blood decreases the secretion of gonadotropins, hormones that stimulate the sex cells. This action explains the cycle disorders, or even an absence of menstruation in women and impotence in men.
Another phenomenon is a macroadenoma of the pituitary can compress surrounding structures, causing headaches, reduced visual field or a pituitary hormone deficits. In the latter case the macroadenoma is causing a hypopituitarism.
Faced with clear signs of hyperprolactinemia, one must first rule out pregnancy, hypothyroidism, or drug causes kidney failure. A blood sample is then to perform a prescribed dosage of prolactin in the blood. According to analytical laboratories, the upper limit is between 15 and 25 ng / ml. A TRH test can also be made: it is after injection of synthetic TRH measure prolactin secretion in response to this stimulation. If there is an answer, the cause of hyperprolactinemia is not pituitary. In contrast, a negative test leads to the conclusion that the presence of a pituitary adenoma. 85% of adenomas do not, in fact, a TRH stimulation.
Brain MRI with gadolinium (or scanner) to confirm the diagnosis, especially in the absence of cause or if the non-pituitary prolactin levels in the blood is greater than 200 ng / ml.
Treatment depends on the cause of hyperprolactinemia. If the cause is drug, simply stopping the offending drug is sufficient to lift hyperprolactinemia. Similarly, if hyperprolactinemia is due to another disease, the treatment of the disease called causal causes disappearance of hyperprolactinemia.
The treatment of adenomas differs according to tumor size. That of the microadenoma (smaller than 10 mm) and is first drug based on the use of molecules that have an anti-secretory and anti-tumor. These drugs are dopamine agonists. If they have no effect or if they cause an intolerance, these drugs are stopped and surgery proposed.
For macroadenomas, the first drug treatment is to reduce the size of the tumor. Then, the adenoma is removed surgically.
Medical specialty that studies the function, diseases and ways to treat the endocrine glands (those that produce hormones) and metabolism (all body functions essential to life as, for example, production and glucose utilization ). Hormone are substances that are transported by the bloodstream and affect various organs and testosterone produced by the testes acts on the bone, skin, fat tissue. Many metabolic functions (blood sugar regulation, serum calcium …) are dependent on hormones.
Any malfunction of the endocrine glands (hyperfunction or hypofunction) or of the receiver (“sensitive”) to a hormone (skin and hair for male and female hormones, for example) will result in disorders (more or less severe) or endocrine disease.
The hormonal imbalance are varied: poor growth, weight loss or, conversely, weight gain, obesity, diabetes, abnormal lipid regulation, infertility, problems of rules …