Which laboratory parameter BEST reflects current nutritional status in a hospitalised patient because of its short half-life?
- A Serum albumin
- B Serum prealbumin (transthyretin) ✓
- C Serum transferrin
- D Total lymphocyte count
Correct answer: B. Serum prealbumin (transthyretin)
Explanation
Prealbumin has a half-life of about 2 days, so it falls and recovers rapidly with changes in protein intake, making it the best short-term marker of visceral protein status. Albumin has a half-life of roughly 20 days, so it reflects nutrition over weeks and is also lowered by inflammation and dilution, which kills option A. Transferrin (half-life about 8 days) is confounded by iron status, and total lymphocyte count is an insensitive adjunct rather than a specific nutritional marker.
Reference: Harrison's Principles of Internal Medicine, 21st ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.