In general, serum creatinine level between 451~707umol/L is considered as renal failure stage. Creatinine is a metabolite produced by muscle in the human body, which is mainly excreted from the body by glomerular filtration, so it can reflect the renal function to a certain extent. The normal value of creatinine is 53-106μmol/L for men and 44-97μmol/L for women, but the value may vary due to different instruments and testing methods in hospitals. Chronic renal insufficiency is clinically categorized into four stages according to blood creatinine. Serum creatinine value is usually 133~177μmol/L is the compensated stage of renal function, serum creatinine value is 186~442μmol/L is the uncompensated stage of renal insufficiency, serum creatinine value is 451~707μmol/L is the stage of renal failure, and when it is more than 707μmol/L, it is the end-stage of renal failure, which is also the stage of uremia. However, serum creatinine is easily affected by age, muscle content, diet and other factors, it is recommended to combine with other test results, medical history and other comprehensive judgment, a single indicator can not be used as a diagnosis of the disease. If there is a significant increase in creatinine, it is recommended to go to a regular hospital in time to give standardized treatment, so as not to delay the condition.