male reproductive endocrinology

Male reproductive endocrine tests are mainly related to the determination of sex hormones (T, FSH, IJH, PRL, E2) and various types of stimulation tests (HCG stimulation test, IMRH stimulation test, clomiphene test). The method is mainly to determine the endocrine function of the patient by measuring the levels of hormones and related metabolites in blood, urine and other body fluids. There are many methods for measuring reproductive endocrine hormones, and radioimmunoassay (RIA) and chemiluminescence immunoassay are currently used. Radioimmunoassay has high sensitivity, and most of them are tested by special kits. The operation method is also convenient and uniform, so the measurement results are stable and accurate. Bioassays used in the past are rarely used, and some laboratories now use more advanced electrochemiluminescence immunoassays. Basic Information Specialist classification: male examination inspection classification: blood examination Applicable gender: whether the male is fasting: fasting Analysis results: Below normal: Normal value: no Above normal: negative: Generally it is normal. Positive: Prompt for infertility. Tips: Before the blood collection, you should fast coffee, strong tea, high sugar and cola drinks; keep your routine and stay up all night. Normal value Serum T, FSH, LH levels were normal and negative. Clinical significance Abnormal result It is possible to determine whether male infertility is caused by endocrine dysfunction by diagnosing male endocrine function. People who need to be checked Male infertility patients. Positive results may be diseases: orgasm disorders, infertility, hypersexuality, sexual dysfunction precautions Taboo before inspection: 1. Coffee, tea, high sugar and cola beverages should be fasted before blood collection. 2, keep a normal work schedule, do not stay up late. 3, if there is a history of dizziness, fainting, please inform the blood collection nurse, in order to take preventive measures. 4. Roll the sleeves to 5 cm above the elbow joint before blood collection. Requirements for inspection: 1. The levels of serum T, FSH and LH in normal people are rapidly pulsed. Therefore, blood samples should be collected once every 20-40 minutes in the morning, at least 3 times. In the measurement, the fractional measurement may be taken or the same amount of blood may be mixed from each of the three specimens and then measured to obtain an average value. 2. Blood is collected in a calm state after intravenous injection of LHRH to avoid emotional agitation. Inspection process First, the determination of sex hormones The levels of serum T, FSH, and LH in normal people are rapidly pulsed. Therefore, blood samples should be collected every 20-40 minutes in the morning, at least 3 times. In the measurement, the fractional measurement may be taken or the same amount of blood may be mixed from each of the three specimens and then measured to obtain an average value. Because the standards used in each laboratory are different, the normal values ​​are also different. Determination of hormones should use standardized methods and techniques as much as possible. The judgment of the results of infertility patients should be checked with reference to the laboratory to check the normal values ​​of males who have been normally born. For male infertility patients, we should first understand serum follicle stimulating hormone, because the most significant serum reproductive endocrine hormone is serum follicle stimulating hormone (FSH), according to its level can be judged that gonadotropin secretion is too high, normal and too low According to this result, it can be initially determined whether the cause of endocrine disorders is in the testis or in the area above the testicle (hypothalamus, pituitary). The indication for this examination is that there is no sperm in the semen, severe spermatozoa (sperm density <5 × 106 / m1), and the patient's test volume is roughly normal. It is also necessary to know the level of serum follicle stimulating hormone in patients with testicular biopsy. Patients with significant FSH abnormalities are not suitable for testicular biopsy. For patients with erectile dysfunction, or with low androgen signs but no elevated FSH, serum testosterone concentrations should be determined to determine the function of testicular Leydig cells and the secretion of androgens. Serum luteinizing hormone (LH) is not routine for reproductive endocrinology in male infertility. In general, FSH and T can be used to detect LH, but for patients with selective LH deficiency (fertileellnuch), serum LH is required. an examination. Increased serum prolactin (PRL) levels may inhibit the normal release of pituitary gonadotropins by acting on the hypothalamus. Therefore, patients with low gonadotropin hypogonadism should be tested for serum PRL. Serum prolactin (PRL) should also be measured in patients with abnormal breast development. Clinically, patients with elevated serum prolactin should be reviewed once, because mental stress may also temporarily increase serum prolactin levels; protein intake can rapidly stimulate the release of pituitary PRL, so should be fasted for at least 3 hours before taking blood; In addition, taking some drugs (such as sedatives, antidepressants, etc.) may also cause an increase in serum prolactin levels, and patients with elevated serum prolactin levels need to be excluded from the effects of the drug. Excluding these interference factors, further consider the hypothalamic and pituitary conditions. In male infertility caused by adrenal or testicular tumors, serum estrogen determination has important reference value for diagnosis. Second, dynamic test In order to further understand the reproductive endocrine of patients, especially to understand the functional reserve of endocrine organs and tissues, to make a more accurate classification of patients, it can be used for dynamic testing of reproductive endocrine hormones. Commonly used dynamic tests are HCG stimulation test, LHRH stimulation test, and clomiphene test. The purpose of the HCG stimulation test is to understand the testicular response to LH. The purpose of the LHRH stimulation test is to identify whether the hypothalamus and pituitary are dysfunctional. The clomiphene test has reference value for understanding the hypothalamic-pituitary-testicular axis integrity. 1. Chorionic gonadotropin (HCG) stimulation test: Human chorionic gonadotropin is a glycoprotein hormone with similar biological activity as LH. In the testis, HCG binds to the LH receptor on the mesenchymal cell membrane, stimulating mesenchymal cell synthesis and secretion of testosterone. The HCG stimulation test can understand the functional status and functional reserve of Leydig cells. Methods: There are many methods for HCG stimulation test. The main difference between the methods is that the dose and regimen for HCG are different. The method described below is relatively simple and practical. HCG 4000 IU was intramuscularly administered once a day for 4 days, and plasma testosterone levels were measured 24 hours after the last injection of HCG. The normal response is that blood testosterone levels increase exponentially from normal (50% to 200% increase). If the blood testosterone level is low, the absolute value of the increase should be calculated. It is also possible to take a simple method of intramuscular injection of HCG (adults 5000 Iu / 1.7 m2, children 00 IU / kg), blood test testosterone 72 to 96 hours after injection. Analysis of results: primary hypogonadal dysfunction, the response was significantly reduced after stimulation; secondary dysfunction of the dysfunction of the pituitary dysfunction was normal; no testis, testicular stromal cells were not developed, testosterone synthesis disorders, etc. There was no response in 1 patient; patients with cryptorchidism had some reaction or delayed reaction (4 to 6 days before reaction). 2. Clomiphene (clomiphene) test: Clomifen (Clomifene), also known as clomiphene, Shu Jingfen, is a non-steroidal substance with a chemical structure similar to that of synthetic diethylstilbestrol, with weak estrogen-like Biological activity. The negative feedback of androgen secreted by Leydig cells to the hypothalamic and pituitary axis is achieved by its conversion to the estrogen in the hypothalamus. Clomiphene enters the human body and can bind to the estrogen receptor of the hypothalamus. Therefore, clomiphene significantly reduces the binding of hypothalamic tissue to estradiol, and blocks the negative feedback of estrogen on the hypothalamus and pituitary axis. As a result, cells secreting gonadotropin in the pituitary gland stimulate the secretion of gonadotropin releasing hormone (GnRH), followed by increased secretion of LH and FSH. The purpose of the clomiphene test is to understand the hypothalamic and pituitary reserve function. Methods: Before the start of the experiment, the basic values ​​of LH, FSH and T were measured. At the beginning, 200 mg of clomiphene was given daily for 2 times for a total of 10 days. On the 9th and 10th day after taking the drug, plasma LH, FSH and testosterone were measured, blood was taken for 20 minutes, blood samples were taken 3 times a day, and 3 times of blood was mixed and measured. Analysis of results: normal human LH increased by 70%-250% on the 10th day of the test than before the administration; FSH increased by 30%-200% on the 10th day of the test than before the test; testosterone increased on the 10th day of the test than before the administration 30%-220%. Each laboratory should have its own normal response values. In patients with hypothalamic or pituitary lesions, the response was significantly reduced. Delayed simple puberty, no response in patients with Kallmanns syndrome. If the base value is very low, the absolute value of the increase should be calculated. 3. LHRH gonadotropin releasing hormone (CnRH) test Gonadotropin releasing hormone (GnRH) is a decapeptide neurohormone secreted by the hypothalamus. GnRH directly stimulates the cells secreting gonadotropin in the pituitary to secrete LH and FSH. The artificially synthesized 10 peptide GnRH was used in the experiment. The gonadotropin releasing hormone (CnRH) test is used to check the pituitary reserve function. Methods: Gonadotropin-releasing hormone (GnRH) administration method is generally performed by intravenous injection. The subjects take the blood on the fasting in the morning to determine the basic value. After 15 minutes, the rapid intravenous injection of GnRH is 100~1.50/Ug, respectively. Blood samples were taken at 30, 45, 60, 90, 120 and 180 minutes to determine plasma LH and FSH concentrations. GnRH can also be intravenously instilled, that is, GnRH240Ug is dissolved in 480ml of normal saline, instilled at 2ml/minq for 240 minutes, 20, 30, 45, 60, 90, 120, 150, 180 after the start of instillation. Blood was taken at 240 minutes and plasma LH and FSH were measured. Analysis of results: LH levels increased in normal male adults 2 to 3 minutes after injection, peaked after about 30 minutes, 2 to 5 times higher than the baseline value; FSH levels rose slowly, about 2 times higher than the baseline value, a few Plasma FSH levels did not increase in normal subjects after GnRH stimulation. If the base value is very low, the absolute value of the increase should be calculated. The gonadotropin-releasing hormone (GnRH) test is useful for identifying whether the lesion is in the hypothalamus or in the pituitary. For example, after injection of GnRH, the blood LH and FSH are elevated, considering the lesion in the hypothalamus; if GnRH is injected, the blood LH and FSH are not Elevation should be considered as a lesion of the pituitary. However, some patients have lesions in the hypothalamus, but the GnRH test does not respond. For this part of the patient, continuous injection or infusion of GnRH can be taken for 7-14 days. If there is still no response, the lesion is in the pituitary gland; if the lesion is in the hypothalamus, GnRH can be returned to normal after 7-14 days of continuous administration of GnRH. Some people believe that this may be due to the long-term lack of GnRH stimulation. Cells secreting gonadotropin in the pituitary gland lose normal ability to respond to GnRH stimulation. After 7 to 14 days of continuous stimulation of GnRH, pituitary function resumes GnRH stimulation. Responsiveness. Note that male patients with hypogonadism respond normally to GnRH, except for gonadal dysfunction caused by mild hypopituitarism, as patients with mild gonadotropin levels respond well to GnRH stimulation test. In patients with primary testicular lesions, LH and/or FSH secretion is overreactive under GnRH stimulation. If the lesion is confined to the seminiferous tubule, the FSH increase response may be abnormal, but the LH response is normal. Not suitable for the crowd Patients who are sensitive to exogenous gonadotropin-releasing hormone and clomiphene. Adverse reactions and risks No complications.

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