Prealbumin
Prealbumin, also know as thyroxine binding prealbumin and transthyretin, is a glycoprotein of approximately 54,000 daltons that is synthesized in the liver. Of all the serum proteins, prealbumin is the best indicator of protein-energy malnutrition because it has a circulating half life of 2 days and responds rapidly to changes in nutritional status. Measurement of prealbumin levels in all newly admitted patients is the most cost effective method of detecting protein-energy malnutrition.
Serum prealbumin levels show a linear relationship to the degree of protein-energy malnutrition.
|
Prealbumin (mg/dL) |
Malnutrition |
|
>17 |
No Risk |
|
10 – 17 |
Moderate Risk |
|
<10 |
Severe |
A low prealbumin concentration is useful in identifying at-risk patients who require careful monitoring and possibly nutritional support. Prealbumin levels should be measured every other day to monitor nutritional support. Levels should increase at a rate of 1 mg/dL per day, if a patient is responding to protein replenishment. Patients can be converted to oral nutrients when the serum level reaches 16 mg/dL or more.
Serum prealbumin concentration is affected by a few non-nutritional factors. Prealbumin is a negative acute phase reactant, which means that levels decrease during inflammation or infection. Severe liver disease may also cause decreased levels. Serum prealbumin is increased by end stage renal disease and glucocorticoid administration.
Reference range is 17 - 39 mg/dL.
Specimen requirement is one SST tube of blood.
