Kidney function cannot be measured by oneself, and it needs to be checked with the help of blood test or double-kidney ECT. When evaluating whether the patient’s kidney function is declining, the main thing is to observe whether the urea and creatinine in the blood are elevated or not, and the other thing is to perform double kidney ECT to observe whether the filtration rate of the kidneys is declining or not. If creatinine and urea are elevated, and at the same time the filtration rate of the kidneys decreases, then it is considered that there is renal failure at this time. However, clinical symptoms can be used to make preliminary speculation, such as whether the patient has blood in the urine, whether there is increased foam in the urine, whether there is an increase in nocturia, more than 5-6 times a night, whether there is anemia, and itching of the skin all over the body, or even recurrent nausea, vomiting, etc. If the patient has any of these symptoms, the patient may have to take the test to see if there is a decrease in renal filtration rate. If the patient has these symptoms, and more than one symptom appears at the same time, it suggests that the possibility of poor renal function is high. If the symptoms appear singly, it is not necessarily, of course, the final diagnosis is still based on the above two tests.