Prealbumin (PAB) Lab Values

Hi there, Abby, here from nursing.com. In this lesson, we’ll discuss prealbumin levels. We’ll talk about the normal value and times when we might see it increased or decreased in clinical. Let’s get started! 

Prealbumin, abbreviated PAB, measures the amount of prealbumin in circulation, and evaluates nutritional status. So, prealbumin, also known as transthyretin, is a protein that’s synthesized by the liver. Did you notice the pre-albumin? It’s actually a precursor to albumin and other proteins in the body. It’s responsible for transporting thyroxine or T4, and vitamin A through circulation, and it’s produced in hepatocytes, like you can see here in this image. 

Some clinical indications for why we would take this lab are to evaluate nutritional status. We need to know particularly what the protein intake looks like. It is also used to monitor when a patient is on TPN to make sure they’re getting adequate nutrients, if a patient is on dialysis, and in the case of needing to evaluate liver function. Normal therapeutic values are between 16 and 30 milligrams per deciliter. This specimen is collected in a serum separator tube. Lab values will be increased in the case of kidney disease. Also, if there’s high dose corticosteroid use. It will also be increased if we have hyperactive adrenal glands or long term, or high dose use of NSAIDs, and also in Hodgkin’s disease. Prealbumin will be decreased in the case of malnutrition. We’re not getting enough in the diet to produce proteins, right? And so, prealbumin being a protein, its production will go down. Did you guess that we were gonna talk about liver disease? Yes. In the case of liver disease, we’re gonna have a decreased value. It will also be decreased in chronic illness, in trauma, particularly that of burns, and also in inflammatory or infectious states. It will also be an issue if there are digestive disorders, therefore, we’d see a lower prealbumin lab value. 

Our linchpins are that PAB, prealbumin, is a precursor to albumin and other proteins that are synthesized in the liver. It’s measured to evaluate nutrition and patients on kidney dialysis, and those that have known impaired liver function. A normal value is between 16 to 13 milligrams per deciliter. We see it increased in the case of kidney disease, certain medications, and Hodgkin’s disease. And we see a decreased value in times of malnutrition, inflammation or infection processes, and in the case of liver disease. 

You all did great on this lesson. This wraps it up for prealbumin. Remember, we love you guys. We know you can do it and as always, happy nursing.

References:

• https://medlineplus.gov/lab-tests/prealbumin-blood-test/#:~:text=A%20prealbumin%20test%20may%20be,you%20are%20in%20the%20hospital.
• https://pathologytestsexplained.org.au/learning/test-index/prealbumin
• https://www.uptodate.com/contents/laboratory-test-reference-ranges-in-adults?search=prealbumin&sectionRank=1&usage_type=default&anchor=H3339720241&source=machineLearning&selectedTitle=3~52&display_rank=3#H3339720241
• https://www.uptodate.com/contents/assessment-of-nutritional-status-in-hemodialysis-patients?search=prealbumin&source=search_result&selectedTitle=8~52&usage_type=default&display_rank=8
• https://ltd.aruplab.com/Tests/Pub/0050435