Getting to know albumin physiology

Serum albumin is a highly sensitive marker for an individual patient's nutritional status. In this video, from our Liver Lab Essentials course, we look at how serum albumin levels can help you to determine whether your patient is suffering from an acute or chronic liver disease.

Interpreting the results of a liver function test can sometimes stump even the most experienced clinicians! In this course, we'll cover which tests to order, the clinical implications of lab abnormalities seen with common liver function tests, and what to do about them. After attending this course, your ability to confidently interpret liver function tests and take the next steps will become second nature!

Albumin is the most abundant circulating protein found in the plasma. It represents half of the total protein content in the plasma of healthy patients. In normal plasma albumin concentration in healthy patients is 3.5 to five grams per deciliter. Albumin is synthesized by liver hepatocytes but very little albumin is stored in the liver.

It is rapidly excreted into the bloodstream at the rate of 10 to 15 grams per day in people with normally functioning livers. In humans, serum albumin functions as a significant modulator of plasma oncotic pressure, and a transporter of endogenous and exogenous ligands, such as drugs.

In clinical medicine, the measurement of serum albumin is a highly sensitive marker for an individual patient's nutritional status. Low albumin levels may indicate malnutrition, liver disease or inflammatory disease. The half-life of albumin is approximately three weeks. When liver function is impaired over a prolonged period, albumin synthesis is impaired which will result in low levels of albumin.

Thus, hypoalbuminemia is a common finding in chronic liver disease. However, a significant reduction in serum albumin level will not be observed in patients with acute liver failure.