How to check if growth hormone secretion is normal

Whether the secretion of growth hormone is normal can be comprehensively judged through five methods: blood testing, urine testing, imaging examination, clinical symptom assessment, and stimulation test.

1. Blood testing:

Serum growth hormone testing is a direct detection method that requires multiple blood samples taken at different time periods. The baseline value test is usually conducted on an empty stomach in the early morning, and the baseline value for normal adults is generally below 5 μ g/L. In response to abnormal growth and development in children, doctors may recommend 24-hour dynamic blood collection to observe secretion rhythms. Blood testing can also synchronously evaluate the levels of insulin-like growth factor-1 and IGF-1, which can more stably reflect the long-term secretion status of growth hormone.

2. Urine testing:

24-hour urine growth hormone measurement can indirectly evaluate the total secretion and is suitable for verification in conjunction with blood tests. This method collects urine samples throughout the day to detect hormone metabolites, avoiding accidental errors in a single blood collection. Children should accurately record their urine output during testing, and maintain a normal diet and daily routine for the three days before testing. Individuals with abnormal urine test results need to undergo further blood confirmation tests.

3. Imaging examination:

Pituitary MRI or CT scan can observe the morphology and structure of the pituitary gland, and screen for organic lesions such as tumors and hyperplasia. Priority should be given to non radiative MRI examinations for pediatric patients, with a scan layer thickness of less than 3 millimeters to clearly display pituitary microadenomas. Imaging reveals abnormal enlargement or contraction of the pituitary gland volume, which should be combined with endocrine examination to determine whether it affects hormone secretion function.

4. Symptom assessment:

The doctor will record in detail the curve of height and weight changes. Children with an annual growth rate of less than 4 centimeters should be alert to insufficient secretion. Adult patients with acromegaly may exhibit characteristic features such as thickening of hands and feet, and protrusion of the lower jaw. The consultation content includes sleep quality, exercise ability, and whether there are symptoms of pituitary compression such as headaches and changes in vision, which may indicate abnormal secretion of growth hormone.

5. Stimulation test:

Insulin hypoglycemia test is the gold standard, which artificially induces hypoglycemia to stimulate pituitary secretion. The commonly used oral stimulation test for children with arginine or levodopa requires monitoring of blood glucose and vital signs in a professional medical institution. During the experiment, if the peak value of growth hormone exceeds 10 μ g/L, it can be judged as normal secretion. If it is below 5 μ g/L, it indicates insufficient secretion. If it is between 5-10 μ g/L, it needs to be comprehensively judged in conjunction with other examinations.

It is recommended that children with growth and development abnormalities monitor their bone age and growth rate every six months, and adults with unexplained physical decline or metabolic abnormalities may consider growth hormone testing. Maintaining a regular daily routine and moderate exercise can help maintain a normal secretion rhythm. Insufficient protein intake may affect growth hormone synthesis. It is recommended to ensure daily intake of high-quality protein such as eggs and fish. Medications that may interfere with the results, such as glucocorticoids or estrogens, should be discontinued according to medical advice before testing. All examination results should be comprehensively interpreted by endocrinologists based on clinical manifestations to avoid self judgment.