Prolactin (PRL) secretion inhibition test

The prolactin (PRL) secretion inhibition test is a test method for measuring the PRL basic value under fasting and resting state, and then taking the bed during oral levodopa test and taking blood again for 3 hours after taking the drug. Basic Information Specialist classification: growth and development check classification: endocrine examination Applicable gender: whether men and women apply fasting: fasting Tips: Pay attention to the normal diet, pay attention to normal work and rest, and prevent endocrine disorders. Normal value After 3 hours of taking the medicine, the PRL inhibition can reach 0.16 nmol/L or less, or the basal value can be reduced by more than 50%. Clinical significance The basal value of patients with prolactinoma is often higher than 4nmol/L and is not inhibited by levodopa. Abnormal results: PRL tumors are common in female patients and occur mostly in the 20 to 40 years old. Female PRL tumors often present as galactorrhea-menopausal syndrome. The tumor size was positively correlated with the patient's serum PRL concentration. The larger the tumor, the higher the PRL level and the more obvious the symptoms. 1. Female PRL tumors are mostly microadenomas, found in young people aged 20 to 30. The typical symptom is amenorrhea-milk-infertility triad. Secondary amenorrhea is more common, accounting for about 90%. Milk spill is the main manifestation of this disease, mostly for touch lactation, accounting for 50% to 90%. Sexual dysfunction accounts for about 60%, complaining of decreased or absent libido, loss of sex, lack of orgasm, and sputum pain. Other symptoms of hypogonadism are shortened menstruation, rare or excessive menstrual flow, delayed menstruation, and infertility. In addition, due to serum reduction caused by breast atrophy, pubic hair loss, vulvar atrophy, vaginal secretions and other symptoms. 2. Male PRL tumor male prolactinoma is generally diagnosed when it is diagnosed, often developing on the saddle, but relatively rare. The main symptoms of sexual dysfunction, accounting for about 83%, can be complete or partial. If the degree of libido declines, impotence, male infertility and the number of sperm decreased. 3. Tumor compression group is more common in large or advanced PRL tumors and other types of pituitary adenomas, hypothalamus and parasagittal tumors due to the huge expansion of the tumor to the saddle and block PIF caused by high PRL. The most common local compression symptoms are headaches and visual abnormalities. The cause of headache is mostly increased intracranial pressure caused by large adenoma, which may be accompanied by nausea and vomiting. The incidence of headache in male PRL tumor patients is higher than that in female patients, about 63%. Some PRL microadenomas may have headaches (50%) although the lesions are not obvious, and the reason is not clear. People who need to be examined: Suspected amenorrhea, galactorrhea, breast atrophy, pubic hair loss, loss of libido, impotence and other symptoms of prolactinoma-related symptoms. Precautions Forbidden before examination: pay attention to normal diet, pay attention to normal work and rest, and prevent endocrine disorders. Requirements for inspection: Actively cooperate with the doctor's request. Disabling drugs that affect PRL secretion. Avoid stimulating the breast during the test. A small number of patients have symptoms such as nausea and dizziness after taking the drug. Inspection process method: 1 Measure the baseline value of PRL in an empty state and then give levodopa 500 mg orally. Bed rest during the test. 2 Blood was taken again 3 hours after taking the drug to check PRL. 3 It can also be used for inhibition test by water load method (20ml/kg body weight in 30 minutes) or bromocriptine (2.5mg orally), which is the same as levodopa test. Not suitable for the crowd Inappropriate people: Patients with heart disease should use this method with caution. Adverse reactions and risks No relevant records.