Prealbumin (Transthyretin)
| Units | Nonpregnant Adult | First Trimester | Second Trimester | Third Trimester |
|---|---|---|---|---|
| mg/dL | 17 – 34 | 8.5 – 32.9 | 16.7 – 30.3 | 8.8 – 28 |
| mg/L | 170 – 340 | 85 – 329 | 167 – 303 | 88 – 280 |
Note: Prealbumin is a short–half-life hepatic protein and decreases in response to inflammation, hemodilution, and reduced hepatic synthesis.
Pregnancy Physiology
- Plasma volume expansion decreases measured prealbumin concentration.
- Hemodilution and increased vascular permeability reduce serum levels.
- Prealbumin is a negative acute-phase reactant and falls with inflammation.
- Maternal nutritional status affects prealbumin more strongly than albumin.
- Low levels do not reliably indicate fetal nutritional issues.
Causes of LOW Prealbumin
- Malnutrition / protein-energy deficiency
- Acute or chronic inflammation (negative acute-phase reactant)
- Liver disease (reduced hepatic synthesis)
- Hyperemesis gravidarum
- Nephrotic syndrome
- Major illness, trauma, burns
- Zinc deficiency (required for prealbumin synthesis)
- Thyroid disease (low in hypothyroidism)
Causes of HIGH Prealbumin
- Dehydration (hemoconcentration)
- High-protein diet
- Chronic kidney disease
- Hodgkin lymphoma
References
1. Lockitch G. Handbook of Diagnostic Biochemistry and Hematology in Normal Pregnancy. CRC Press; 1993.
2. Abbassi-Ghanavati M, Greer LG, Cunningham FG. Pregnancy and laboratory studies: a reference table for clinicians.
Obstet Gynecol. 2009;114:1326-31.
PMID: 19935037