Cystatin C 1.48mg/L does not require treatment and is within the normal range. The normal range of cystatin C is 0.6~2.5mg/L, which is mainly used to evaluate glomerular filtration function in clinic, and is widely used in diabetic nephropathy and renal transplantation chemotherapy. Compared with blood creatinine and urea nitrogen, cystatin C is more sensitive in determining the early damage of renal function. Cystatin C, short for cysteine protease inhibitory protein C, can be expressed by almost all kinds of nucleated cells in the body, and the daily secretion is relatively fixed, and it can pass through the glomerular filtration membrane freely, so it is a sensitive and specific indicator reflecting the glomerular filtration function. It is a sensitive and specific indicator to reflect the glomerular filtration function. If this indicator is found to be elevated in the clinic, it is necessary to find out the cause of the disease under the guidance of professional doctors and target treatment.