Multiple methods of testing for hyperprolactinemia

What are the examination methods for hyperprolactinemia? This is what everyone is more concerned about. Only by understanding the examination methods for hyperprolactinemia can we help everyone further implement treatment and ensure everyone's safety. Next, we will give a detailed interpretation of the examination methods for hyperprolactinemia.

Hyperprolactinemia test method:

1. Principle TRH stimulates pituitary TSH cells and prolactin (PRL) cells to secrete TSH and PRL. In patients with hypothyroidism, low blood thyroid hormone weakens the negative feedback effect on pituitary TSH, causing TSH to overreact to TRH; excessive blood thyroid hormone strengthens the negative feedback effect on pituitary TSH, causing TSH to underreact to TRH.

2. Methods: TSH was measured by taking venous blood before injection. 10 minutes later, 300-500 μg of TRH was injected intravenously. The injection was completed within 15-20 seconds. Blood was taken at 0, 30, and 60 minutes to measure TSH. In normal people, TSH reaction reached a peak 20-30 minutes after injection of TRH. △TSH ​​(△TSH = TSH peak value - TSH basal value) was 2-30 μU/ml. TSH basal value = the average of TSH 10 minutes before injection and TSH 0 minutes before injection. The reaction of TRH test is related to age and gender. The normal reaction of women is △TSH ​​= 6-20 μU/ml. The reaction of men is lower than that of women. The △TSH ​​of men over 40 years old is > 2 μU/ml. The TRH test reaction of primary hypothyroidism is too strong; the TSH reaction of hyperthyroidism patients, Grayes ophthalmopathy with partial euthyroidism, or patients with excessive oral glucocorticoids is poor.

3. FSH and LH decreased in the hypothalamus-pituitary-ovarian axis reproductive hormone test, and the LH/FSH ratio increased. If PRL ≤ 100ng/ml, it is mostly functional increase, and PRL ≥ 100ng/ml is mostly tumor increase. The larger the tumor, the higher the PRL. For example, if the tumor diameter is ≤ 5mm, the PRL is (171±38)ng/ml; if the tumor diameter is 5-10mm, the PRL is (206±29)ng/ml; if the tumor diameter is ≥ 10mm, the PRL is mostly (485±158)ng/ml. Plasma PRL may not increase when giant adenomas bleed and necrotize.

4. Thyroid, adrenal and pancreatic function tests: When hyperprolactinemia is combined with hypothyroidism, TSH is elevated, and T3, T4, and PBI are decreased. When hyperprolactinemia is combined with Cushing's disease and virilization symptoms, testosterone (T), androstenedione (△4dione), dihydrotestosterone (DHT), dehydroepiandrosterone (DHEA), 17-ketosteroids (17KS) and plasma cortisol are elevated. When hyperprolactinemia is combined with diabetes and acromegaly, plasma insulin, blood glucose, glucagon should be measured and a glucose tolerance test should be performed.

5. Prolactin stimulation test

(1) Thyrotropin-releasing hormone (TRH) test: In normal women, a single intravenous injection of TRH 100-400 pg is given. Within 15-30 minutes, PRL increases 5-10 times compared to before injection, and TSH increases 2 times. There is no increase in patients with pituitary tumors.

(2) Chlorpromazine test: Chlorpromazine inhibits norepinephrine reabsorption and dopamine function through receptor mechanism, and promotes PRL secretion. In normal women, after intramuscular injection of 25-50 mg of chlorpromazine, blood PRL increases 1-2 times compared with before injection 60-90 minutes later and lasts for 3 hours. It does not increase in pituitary tumors.

(3) Metoclopramide test: Metoclopramide promotes the production and release of PRL. In normal women, 30 to 60 minutes after intravenous injection of 10 mg, PRL increases by more than 3 times compared with before injection, but does not increase in patients with pituitary tumors.

The above-mentioned hyperprolactinemia examination method has been tested in practice. When choosing the hyperprolactinemia examination method, you must combine your own actual situation. Only by going to a regular hospital can you guarantee everyone's safety to the greatest extent.