In addition to bilirubin, albumin is another mainstay on a typical liver function panel. Let’s review how albumin is formed, its functions, and what serum albumin levels can tell us about your patients’ health.
Where is albumin formed and what does it do?
Albumin is the most abundant circulating protein found in the plasma. It represents half of the total protein content in the plasma of a healthy patient. A normal plasma albumin concentration in a healthy patient is 3.5–5.0 g / dL.
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 10–15 g / day in people with normally functioning livers.
In humans, serum albumin functions as a significant modulator of plasma oncotic pressure and as a transporter of endogenous and exogenous ligands (e.g., drugs).
What can serum albumin measurements tell us?
In clinical medicine, serum albumin measurements are a highly sensitive marker of a patient's nutritional status. Low albumin levels may indicate malnutrition, chronic 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 also impaired, which results in low levels of albumin. For this reason, hypoalbuminemia is a common finding in chronic liver disease. However, a significant reduction in serum albumin levels is not observed in patients with acute liver failure.
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