Albumin is the most abundant protein in serum. More than 50% of all soluble protein in serum is albumin. Albumin is needed for maintaining blood oncotic pressure, as a carrier molecule, and for maintaining normal blood pH. Hypoalbuminemia leads to leakage of fluids into tissues, causing edema. Blood albumin concentrations are used in identifying problems in fluid balance, assessing kidney, liver and intestinal function, and in monitoring inflammatory diseases.