Albumin is a crucial protein found in human plasma, responsible for maintaining body nutrition and osmotic pressure. It accounts for approximately 50% of the total plasma protein, with a concentration range of 38-48g/L. The liver produces about 12-20g of albumin daily. The structure of mature albumin is made up of a single chain of polypeptides, containing 585 amino acid residues in an oval shape. Additionally, the concentration of globulin is typically around 15-30g/L. The a/g ratio, which is vital for clinical significance, usually ranges between 1.5-2.5:1. An increase in a/g may result from malnutrition or a lack of immunoglobulin, whereas a decrease may be caused by a drop in albumin synthetic ability or an increase in globulin. Factors that may contribute to a decrease in albumin include renal sclerosis, protein exudation from gastrointestinal inflammation, liver cirrhosis, burns, malignant tumors, and an increase in antibody due to infectious diseases. When a patient has liver cirrhosis, a decrease in serum albumin and a/g ratios is a significant clinical indicator of liver function.
