Renal failure is divided into 3 stages, which are azotemia stage, renal failure stage and uremia stage. The following is a specific analysis: 1. Azotemia stage refers to creatinine between 177-442 μmol/L, with symptoms such as poor circulation, weakness, swelling of the lower limbs and elevated blood pressure. 2. Renal failure stage refers to creatinine between 443-707 μmol/L, with symptoms such as swelling, anemia, elevated blood pressure, weakness and poor circulation. 3. Uremia stage refers to creatinine >707 μmol/L, with symptoms such as generalized swelling, low or no urine output, weakness and uremia. μmol/L, symptoms mainly include generalized swelling, low or no urine output, weakness, anemia, elevated blood pressure and other symptoms.