What does the hGH . test mean?

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Growth hormone is called Growth hormone (referred to as hGH hormone). This is a hormone of the pituitary gland, necessary for the growth and development of the body, especially in children. The hGH test is often used to identify hGH deficiency and thereby help evaluate pituitary function.

1. Overview of hGH . growth hormone

Human Growth Hormone (hGH) is a natural hormone produced by the pituitary gland and is important for cell growth, reproduction and reproduction.
HGH helps maintain, grow and repair healthy tissues in the brain and other organs. This hormone may help speed healing after injury and repair muscle tissue after exercise. This helps in building muscle mass, boosting metabolism and burning fat. HGH is also believed to benefit skin quality and appearance, helping to slow the aging process and treat age-related diseases.
HGH works by activating cellular metabolism, stimulating the liver to make an insulin-like protein that produces cartilage cells. This plays a part in the development of bones and organs, as well as muscle protein synthesis.

2. What is the hGH test for?

The hGH growth hormone test is commonly used to identify hGH deficiency and thereby help evaluate pituitary function, often to monitor abnormal results of other pituitary hormone tests.
The hGH test is also used to detect an excess of hGH, thereby helping to diagnose and monitor treatment of gigantism and acromegaly.
hGH is important for normal growth and development in children and helps to regulate metabolism in both children and adults. The pituitary gland produces and releases hGH into the bloodstream in bursts throughout the day, so a single blood hGH measurement is usually of no clinical benefit. Therefore, testing to inhibit or stimulate the release of hGH from the pituitary gland is usually performed.
The hGH stimulation test helps diagnose hGH deficiency and hypopituitarism. A blood sample for the hGH stimulation test is taken on a fasting basis, usually after 10-12 hours of fasting. The patient is then injected intravenously with a substance that stimulates the release of hGH from the pituitary gland. Next, blood samples are taken at different intervals and hGH levels are tested during each blood draw to see if the pituitary gland is stimulated to produce hGH. The most commonly used hGH stimulants are arginine, clonidine, and glucagon. Since exercise often causes an increase in the secretion of hGH into the bloodstream, vigorous exercise can also be used as a stimulant of hGH secretion.
The hGH suppression test helps diagnose hGH excess. A blood sample for the hGH suppression test is also taken in the fasting period, after 10-12 hours of fasting. Next, the patient is given a standard glucose solution (usually 100 grams of glucose) by mouth. Then blood samples are taken at different intervals and hGH levels are tested at each blood draw to see if the pituitary gland is suppressed by the oral dose of glucose.
HGH also stimulates the production of Insulin-like growth factor-1 (IGF-1). IGF-1 is a hormone that mediates the effects of GH and helps promote normal bone and tissue growth and development. However, unlike hGH, the level of IGF-1 in the blood is stable throughout the day, so the IGF-1 test is often used to help evaluate hGH deficiency or excess.

Testing for IGF-1 and hGH suppression may also be used to monitor pituitary tumor treatment. In patients with tumors, can hGH and IGF-1 levels be measured after tumor removal to determine if the entire tumor has been successfully removed? Years later, these tests may be ordered to monitor hGH production and to detect tumor recurrence.

3. In what cases is the hGH test indicated?

3.1 For hGH stimulation test The hGH stimulation test may be ordered in children when the child has signs and symptoms of hGH deficiency, including:
Slowed growth rate Small stature than children of the same age Delayed puberty Bone growth retardation (detected by x-rays) hGH stimulation test may be used in adults when there are signs and symptoms of deficiency hGH, hypopituitarism, such as:
Decreased bone density Fatigue Dyslipidemia, such as high cholesterol Decreased exercise tolerance Other hormone tests, such as those for Thyroid function is usually done first to rule out conditions that cause similar symptoms. Deficiency of hGH is rare in children and adults. The deficiency of hGH can be seen in adults when we have been diagnosed with hGH deficiency as a child or we have a history of disease in the hypothalamus or pituitary gland.
3.2 For hGH suppression testing Clinically, hGH suppression testing is uncommon. They are usually done when a child or adult has signs and symptoms of an excess of hGH such as gigantism or acromegaly.
In cases where a pituitary tumor is suspected to be causing an excess of hGH, an hGH suppression test may also be ordered and may sometimes be used in conjunction with testing for IGF-1 and other hormone levels. to monitor the effectiveness of treatment for these diseases.
As mentioned above, hGH and IGF-1 suppression tests can also be used at certain intervals over many years to monitor for an abnormal recurrence of hGH excess.

4. Reference value

Blood hGH values ​​in healthy people are:
In newborns: < 5-40 ng/mL or 226-1808 pmol/L In children: < 0-20 ng/mL or 0-904 pmol/L Adults: In men: < 5 ng/mL or < 226 pmol/L. In women: < 10 ng/mL or < 452 pmol/L.

5. Clinical significance

5.1 Clinical significance of hGH stimulation testing If hGH stimulation levels are not significant during testing (i.e. hGH levels are still below what is needed) and the person again has signs and symptoms If the patient is hGH-deficient and has low IGF-1 levels, it is concluded that the patient is hGH-deficient and needs to be treated.
If our TSH and T4 levels are abnormal, then we may have thyroid dysfunction, hypopituitarism or hypopituitarism, leading to symptoms similar to hGH deficiency. Therefore, before thyroid function is evaluated, testing to identify hGH deficiency should not be performed. A child with hypothyroidism needs to be treated and his or her growth rate assessed before hGH testing is considered.
If a person exercises at a vigorous intensity without a corresponding increase in hGH levels, he or she may have an hGH deficiency. This case will need to be further evaluated with other tests.
5.2. Clinical significance of the hGH suppression test If the hGH suppression test is not significant, it is still above what is needed and the person again has signs and symptoms of hGH excess. (as in gigantism or acromegaly) and having a high level of IGF-1 means that the person is producing too much hGH. If a patient has a tumor detected on an X-ray, CT scan, or MRI, it is likely a pituitary tumor (usually benign). If hGH levels are increased in a person being monitored for a tumor, there may be a recurrence of that tumor.
Tumors in the pituitary gland are one of the most common causes of overproduction of hGH, but they can also cause a deficiency. The presence of a pituitary tumor can affect the production of hGH along with it can affect the production of other pituitary hormones: ACTH (increased in Cushing's syndrome) or prolactin. If the tumor is relatively large, it can inhibit the production of all pituitary hormones and cause damage to surrounding tissues.

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