Routine physical examination shows no kidney function

Don’t be fooled by this statement - basic routine physical examination packages purchased by most units and priced at hundreds of dollars on the market include two core renal function indicators, creatinine and urea nitrogen. People think that "kidney function is not checked". Essentially, the renal function of routine physical examination is too "crude" and can only reveal kidney damage that has progressed to the middle and late stages, and early problems cannot be seen at all.

Two months ago, I accompanied my elders in the family to the community hospital to get the physical examination report. All the values ​​in the column of her kidney function were stuck in the reference range, and they were all normal downward arrows. But during that time, she always said that she had to urinate frequently at night, and had to urinate three or four times a night. Her legs were always so swollen by the afternoon. I took her to the nephrology department for registration. The doctor prescribed a routine urine test and a urine microalbumin test. The results showed that the urine microalbumin was three times higher than the upper limit of normal, which is typical early diabetic kidney damage. She had a 10-year history of diabetes, and her kidney function had been normal every year in previous physical examinations, but she just missed it.

To put it bluntly, the kidney function indicators selected for routine physical examination are too "slow". Take the most commonly used creatinine as an example. The compensatory capacity of our kidneys is so strong that it is equivalent to the work of 100 employees. As long as the remaining 30 can hold on, the "performance" output, that is, the creatinine value, will be stable within the normal range. When you see an increase in creatinine on the physical examination report, it means that at least 70% of the nephrons are no longer able to work. This is an irreversible injury with very little room for intervention.

The physical examination industry and clinical departments have been arguing for a long time about whether to add more detailed renal function tests to routine physical examinations. Many friends who are designing physical examination packages have complained to me. The price of the basic package is only a few hundred yuan, and the goal is to screen out serious and fatal diseases. If a bunch of detailed items are added, the unit price will be too high for ordinary people, and in the end it will not be sold. Moreover, the kidneys of most healthy young people are already fine, so adding a lot of them is a waste of resources. However, doctors in the Department of Nephrology generally feel that it is too much of a disadvantage: just add a 10 yuan urine routine and a 20 yuan urine microalbumin/creatinine ratio to screen out more than 90% of early kidney injuries. The cost-effectiveness is ridiculously high. Early detection and early intervention can completely avoid the development of uremia.

In fact, there is no need to worry about who is right or wrong, just choose according to your needs. If you are only in your early twenties, have no underlying medical conditions, and do not take blind prescriptions, painkillers or other kidney-damaging things, the two kidney function indicators in the routine physical examination are enough, and there is no need to spend extra money on additional items. But if you have chronic diseases such as high blood pressure, diabetes, gout, or have a family history of kidney disease, and you always have headaches and brain fever, you take ibuprofen and acetaminophen, and you always believe in "kidney-tonifying remedies" and blindly take supplements. Next time you have a physical examination, take the initiative to tell the front desk to add urine microalbumin. You can buy it for tens of dollars, and you can rest assured that it is really not a loss.

By the way, there is another common misunderstanding. Many people equate "kidney deficiency" in traditional Chinese medicine with the kidney function in western medicine. Last time I met a 25-year-old young man in the outpatient clinic. He said that his recent backache and hair loss must be due to poor kidney function. He took the physical examination report to the doctor for a checkup. The result was that all indicators were normal. He just stayed up until three o'clock every day and drank eight meals a week. Just go back and adjust your work and rest. It has nothing to do with kidney damage. Don't scare yourself.

To put it bluntly, the renal function test in routine physical examination is not to check whether your kidneys are good or not, but to check whether your kidneys are about to fail. If you really care about your kidneys, doing less is better than doing anything else. If you are really uncomfortable, don’t bear it, and don’t just focus on the reference range of the physical examination report. Seeking a specialist is much more reliable than blindly checking the information yourself.