renal tubular glucose reabsorption test

After the normal human blood glucose is completely filtered from the glomerulus, the proximal tubules are all actively reabsorbed, and no sugar is excreted in the urine. This reabsorption is carried out in reverse concentration. The reabsorption mechanism is that the carrier protein (transporter) on the membrane of the proximal tubule epithelial cells combines with Na+ and glucose to form a complex, which can be reabsorbed through the tubular membrane. blood. Since there is a certain amount of carrier protein on the cell membrane, there is a limit to the transport of glucose. When the blood glucose level rises to a certain level, the reabsorption capacity of the renal tubules is saturated, and excessive sugar cannot be reabsorbed, and urine sugar appears. Even if the blood sugar concentration is higher, the reabsorption value does not increase any more, and this is TmG. By subtracting the amount of glucose present in the urine per unit time from the amount of glucose filtered out from the glomerulus per unit time, the TmG value can be obtained, and the value of the value can reflect the number and function of the effective nephron. One of the indicators of the end-tube reabsorption function. Basic Information Specialist classification: urinary examination classification: urine / kidney function test Applicable gender: whether men and women apply fasting: not fasting Analysis results: Below normal: TmG is related to the number of effective nephrons. When the glomeruli of some nephrons are occluded, glucose cannot be filtered; when the tubules are ischemic or damaged, glucose cannot be reabsorbed, both of which can reduce the TmG value. The number of effective nephrons can be estimated according to the degree of reduction, but the glomeruli or renal tubules cannot be identified. The other pathological significance is the same as TmPAH. Normal value: The maximum reabsorption of renal tubular glucose (male): 300-450mg / (min · 1.73m2) The maximum reabsorption of renal tubular glucose #?50-350mg/(min·1.73m2) Above normal: No clinical significance. negative: Positive: Tips: Please cooperate with the doctor when checking. Normal value 340±18.2 mg/(min·1.73 m2), male 300-450 mg/(min·1.73 m2), female 250-350 mg/(min·1.73 m2). Clinical significance Normal people's urine sugar is negative. When blood sugar is 8.96 ~ 10mmol / L (160 ~ 180mg / dl), diabetes can occur, this value is called the kidney sugar threshold. If the blood sugar is normal, the glucose tolerance test is normal, and the urine sugar is positive, called renal glucosuria, which is caused by the decrease of proximal tubule reabsorption. TmG is related to the number of effective nephrons. When the glomeruli of some nephrons are occluded, glucose cannot be filtered; when the tubules are ischemic or damaged, glucose cannot be reabsorbed, both of which can reduce the TmG value. The number of effective nephrons can be estimated according to the degree of reduction, but the glomeruli or renal tubules cannot be identified. The other pathological significance is the same as TmPAH. Low results may be diseases: glomerulonephritis, acute tubulointerstitial nephritis considerations TmG is an index for measuring the number of proximal tubules. Because of strict conditions and complicated operation, it is rarely used clinically. Inspection process With the renal tubular function test method. Not suitable for the crowd no. Adverse reactions and risks no.

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