Cystatin C is usually more accurate in determining kidney function. Cystatin C, known as cysteine protease inhibitor, is generally filtered through the glomerulus, and its metabolism is relatively constant, reflecting the glomerular filtration function, which is a constant indicator. Through the patient’s age, gender, body weight and so on, combined with cystatin C, blood creatinine and other indicators, can estimate the glomerular filtration rate, make an effective assessment of renal function, and usually determine the renal function is more accurate. Therefore, cystatin C is a key indicator in kidney function test. If the cystatin C index is found to be high or low, it is recommended to cooperate with professional doctors to complete a series of tests as soon as possible to clarify whether you are suffering from renal system diseases. If kidney disease is found, it is recommended to cooperate with doctors to carry out standardized treatment in time to control the development of the disease and avoid further aggravation.