Renal failure can not be seen by ultrasound, renal ultrasound can show renal atrophy, which can only support chronic renal failure. Kidney failure needs to check kidney function for screening, the current methods of checking kidney function are blood creatinine, endogenous creatinine clearance, renal ECT. blood creatinine due to age, gender, muscle atrophy, nutritional status of the impact of the blood creatinine, especially when the blood creatinine in the critical value of the high value, the accuracy and the density of the spirit of the decline, can not be accurately determine whether the renal failure. Endogenous creatinine clearance is less affected by external factors and reflects renal function more accurately, but it requires 24 hours of urine to calculate, so the specimen is prone to error. Renal ECT is a more accurate and objective assessment of glomerular filtration rate. Chronic renal failure is a chronic progressive disease until the end stage of renal failure, i.e. uremia, once the symptoms of uremia appear, for example, digestive symptoms, such as nausea, vomiting, severe upper gastrointestinal bleeding, chest tightness, shortness of breath, dyspnea, at this time, it is necessary to carry out hemodialysis or peritoneal dialysis treatment.