Abstract

Hypoalbuminemia (or hypoalbuminaemia) is a medical sign in which the level of albumin in the blood is abnormally low. It is a type of hypoproteinemia.

Albumin is a major protein in the human body, making up about 55-60% of total human plasma protein by mass. Many hormones, drugs, and other molecules are mostly bound to albumin in the bloodstream and must be released before becoming biologically active. For example, calcium binds to albumin and hypoalbuminemia leads to an increase in free ionized calcium.

Albumin is synthesized in the liver, and low serum albumin may be indicative of liver failure or diseases such as cirrhosis or chronic hepatitis. Hypoalbuminemia can also present as part of the nephrotic syndrome, in which protein is lost in the urine due to kidney damage. Low albumin levels can be an indicator of chronic malnutrition or protein losing enteropathy.

Hypoalbuminemia may cause generalized edema (swelling) via a decrease in oncotic pressure.

The serum albumin level is part of a standard panel of liver function tests. Levels below 3.5 grams per deciliter are generally considered low.

A low serum anion gap is frequently caused by hypoalbuminemia.