High A1 globulin refers to high α1 microglobulin, which is commonly found in renal tubular injury caused by various diseases, such as nephrotic syndrome, diabetic nephropathy, glomerulonephritis or hypertensive nephropathy, etc. It is recommended to consult with a specialist. 1. α1 microglobulin is a glycoprotein, can freely pass through the glomerulus is serum free α1 microglobulin, urinary α1 microglobulin can be reabsorbed by the renal tubules, so there is also a small amount of α1 microglobulin in the urine. 2. The normal value of adult urinary α1 microglobulin is <15mg/24h, and the normal value of serum free α1 microglobulin is 10-30mg/L. The results may vary with different examination machines. 3. High α1 microglobulin is commonly seen in glomerular or tubular injury caused by various diseases: (1) Proximal tubular injury: high urinary α1 microglobulin can be specific and sensitive to detect early tubular injury, such as rejection after renal transplantation, etc., and is not affected by malignant tumors, which is more reliable than β2 microglobulin. (2) Impaired glomerular filtration function: high blood α1 microglobulin suggests that the glomerular filtration rate has decreased, and if combined with high urinary α1 microglobulin, it indicates that the glomerular filtration rate and tubular absorption function are both impaired, especially in the early stage. If you have high serum or urine α1-microglobulin, we suggest you to consult the hospital in time to find out the reason and follow the doctor's advice to treat it actively.