Glucose tolerance test

The Glucose Tolerance Test (GTT) is a glucose load test used to understand the body's ability to regulate glucose. When the islet β-cell response is normal, the elevated glucose concentration can be adjusted to the normal range at 2 to 3 hours. When the fasting plasma glucose concentration is between 6 and 7 mmol/L and it is suspected of being diabetic, it is necessary to confirm the diagnosis by this test. Basic Information Specialist classification: growth and development examination classification: blood examination Applicable gender: whether men and women apply fasting: fasting Tips: Stop all drugs before and during the test, especially those that have an impact on this test, such as hydrochlorothiazide, adrenal cortex hormones. Normal value The glucose tolerance of normal people increased the peak of serum glucose level from 0.5 to 1 h after oral glucose, from 7.78 to 8.89 mmol/L (140-160 mg/dl). After 2 hours, the blood glucose level was restored to normal, and the urine glucose test was negative in each urine sample. Clinical significance Abnormal result 1. Patients with acute hepatitis have a sharp increase in blood glucose between 0.5 and 1.5 hours after taking glucose, which can exceed normal. 2. Endocrine diseases, such as adrenal hyperfunction (such as Cushing's syndrome), 70% to 80% of patients have impaired glucose tolerance, and vice versa, adrenal insufficiency, anterior pituitary dysfunction, etc. Tolerance curve. 3. Patients with chronic pancreatitis often present with a diabetes curve. 4. Liver disease, chronic hepatitis patients may have impaired glucose tolerance. 5. Impaired glucose tolerance may occur in the acute phase of myocardial infarction, which may be related to the patient's stress state. 6. Obesity may have abnormal glucose tolerance curve. As fat cells are not sensitive to insulin, glucose tolerance can often be reduced. Simple obesity glucose tolerance can also be normal or a low-flat curve. 7. Renal glucosuria due to renal tubular reabsorption function, renal sugar threshold decreased, so that the normal concentration of glucose in the glomerular filtrate can not be completely reabsorbed, the occurrence of diabetes, called renal glucosuria. People who need to be checked 1. No symptoms of diabetes, random or fasting blood glucose abnormalities. 2. No symptoms of diabetes, transient or persistent diabetes. 3. No symptoms of diabetes, but a family history of significant diabetes. 4. There are symptoms of diabetes, but random or fasting blood glucose is not enough diagnostic criteria. 5. Pregnancy, hyperthyroidism, liver disease, infection, and diabetes. 6. Women who give birth to a huge fetus or individuals with a large fetal history. 7. Unexplained kidney disease or retinopathy. Low results may be diseases: hypoglycemia, obesity, hypoglycemia syndrome in the elderly 1. Avoid testing under electrolyte imbalance or stress. 2. All drugs are deactivated before and during the test, especially those that have an effect on the test, such as hydrochlorothiazide and adrenocortical hormone. 3, this test should not be regarded as a specific test for the diagnosis of diabetes, the diabetes curve or impaired glucose tolerance are not all diabetes, the test results of patients with liver and kidney disease, the elderly or pregnancy should be more cautious. 4. This test should be carried out in the morning. If it is carried out in the afternoon, the original normal tolerance may be reduced. It has been clearly diagnosed as a diabetic patient and this test is forbidden. In the test, it is advisable to simultaneously take blood to measure insulin levels (insulin release test). 5, gastrointestinal tract dysfunction or nausea, vomiting and pregnant women should use intravenous method. Inspection process (1) The patient can eat normally 3 days before the test (the amount of carbohydrates consumed per day should not be less than 250-300g), and insulin therapy should be stopped. No more food after dinner 1 day before the test. (2) 2 ml of venous blood was taken on an empty stomach in the morning, anticoagulation, and urine samples were collected at the same time to measure the glucose content in blood and urine. (3) 100 g of glucose was dissolved in 300 ml of warm water (or 1.75 g of glucose per kg body weight, dissolved in 2.5 ml of water per gram). Subjects were given one dose at a time, and blood was taken once at 0.5h, 1h, and 2h after the service, and urine samples were collected at the same time to measure blood sugar and urine sugar. Not suitable for the crowd Generally no taboos. Adverse reactions and risks Dizziness or fainting: When blood is drawn, due to emotional overstress, fear, reflex caused by vagus nerve excitability, blood pressure drop, etc., the blood supply to the brain is insufficient to cause fainting or dizziness.