Three routine examination items for renal insufficiency

For most middle-aged men, keeping their kidneys healthy is a very important thing in life. In order to know whether their kidneys are healthy, they have to go to the hospital for routine kidney function tests, but there are so many test items that many men find it difficult to choose. So, what are the most important items for kidney dysfunction tests?

1. Routine kidney function tests that reflect renal blood flow:

Determination of aminohippuric acid clearance rate, phenol red excretion test, etc.

Some kidney function damage can appear before symptoms appear. Kidney function tests can detect kidney disease early, understand the location and extent of kidney damage, and help diagnose and guide treatment. However, kidney disease does not necessarily mean kidney function damage, because the kidney has a large reserve capacity. Some kidney function abnormalities only appear when kidney damage is obvious.

2. Creatinine clearance test

This is more common when the kidney function is checked to determine the degree of glomerular damage. Eat a low-protein diet for three days before and on the day of the test, do not eat meat, and avoid strenuous exercise. Void all urine at 8 a.m. on the day of the test, and then collect the urine in a clean container with toluene preservative for 24 hours from then to 8 a.m. the next morning. Draw 2 to 3 ml of venous blood on the day of the test. Send blood and urine for testing at the same time. The normal range is 109 to 148 liters/24 hours (or 80 to 120 ml/min), and the average is 128 liters/24 hours (or 100 ml/min). A clearance rate less than 80% of the normal value indicates a reduction in glomerular filtration function. A clearance rate of 70-51 ml/min is mildly reduced, 50-31 ml/min is moderately reduced, and less than 30 ml/min is severely reduced. A clearance rate of 20-11 ml/min is early renal insufficiency, 10-6 ml/min is late renal insufficiency, and less than 5 ml/min is terminal renal insufficiency.

3. Determination of nitrogen and serum creatinine

This is a common test for kidney function. Take 1 ml of venous blood, inject it into an anticoagulant tube, and mix it thoroughly. Normal blood urea nitrogen is 9-20 mg/L, and blood creatinine is 1-2 mg/L. Various serious kidney diseases cause renal insufficiency and increase blood urea nitrogen. Upper gastrointestinal bleeding, severe infection, and excessive protein in the diet can temporarily increase blood urea nitrogen. Blood creatinine concentration is less affected by factors such as diet. When it increases significantly, it indicates a poor prognosis.