Prealbumin

Definition

Prealbumin is a protein synthesized by the liver, primarily serving as a transport protein for thyroxine and retinol-binding protein. It is often used as a nutritional marker to assess protein status and is particularly sensitive to changes in dietary intake, making it a valuable indicator for malnutrition and other health conditions, including cancer.

5 Must Know Facts For Your Next Test

1. Prealbumin has a shorter half-life (about 2-3 days) compared to albumin, making it a more responsive marker for assessing short-term changes in nutritional status.
2. Normal prealbumin levels range from 15 to 36 mg/dL, and levels below 10 mg/dL often indicate severe malnutrition or acute illness.
3. Because prealbumin is affected by hydration status, it's important to consider fluid balance when interpreting test results.
4. In patients with cancer, prealbumin levels may decrease due to increased metabolic demands or reduced intake, indicating potential malnutrition risk.
5. Prealbumin levels can be influenced by liver function; compromised liver function may lead to lower synthesis of prealbumin.

Review Questions

• How does prealbumin serve as an indicator of nutritional status, and why is it preferred over other proteins like albumin for short-term assessments?
  • Prealbumin is a sensitive marker for assessing nutritional status because of its short half-life, which allows it to reflect recent dietary intake more accurately than longer-lasting proteins like albumin. While albumin can indicate chronic malnutrition or liver issues, prealbumin levels can change rapidly with fluctuations in nutrition, making it particularly useful in clinical settings where immediate dietary intervention is necessary.
• Discuss the implications of altered prealbumin levels in patients with cancer and how this information can guide nutritional interventions.
  • Altered prealbumin levels in cancer patients can signify inadequate nutritional intake or increased metabolic demand due to the disease. Lower prealbumin levels often correlate with a higher risk of malnutrition, which can lead to poorer treatment outcomes and decreased quality of life. Understanding these changes enables healthcare professionals to tailor nutritional interventions that address specific needs, potentially improving patient recovery and overall health.
• Evaluate the role of prealbumin in the context of interpreting biochemical test results for patients experiencing inflammation or infection.
  • In cases of inflammation or infection, interpreting prealbumin levels requires careful consideration because they can be influenced by acute phase responses. While low prealbumin may suggest malnutrition, it could also reflect changes due to systemic inflammation that increase other markers like C-reactive protein (CRP). Therefore, a comprehensive evaluation that includes understanding the patient's overall clinical picture is essential to distinguish between nutritional deficiency and effects caused by illness.

Related terms

Albumin: A major plasma protein that helps maintain osmotic pressure and transport various substances in the blood; lower levels may indicate malnutrition or liver dysfunction.

Nutritional Status: The condition of the body as it relates to the intake and utilization of nutrients; can be assessed through various indicators, including serum proteins.

C-Reactive Protein (CRP): An acute-phase protein that increases in response to inflammation; can provide context when interpreting prealbumin levels, especially in illness.