Clinical Information Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test
Albumin is a carbohydrate-free protein, which constitutes 55% to 65% of total plasma protein. It maintains oncotic plasma pressure, is involved in the transport and storage of a wide variety of ligands, and is a source of endogenous amino acids. Albumin binds and solubilizes various compounds, including bilirubin, calcium, long-chain fatty acids, toxic heavy metal ions, and numerous pharmaceuticals.
Hypoalbuminemia is caused by several factors: impaired synthesis due either to liver disease (primary) or due to diminished protein intake (secondary); increased catabolism as a result of tissue damage and inflammation; malabsorption of amino acids; and increased renal excretion (eg, nephrotic syndrome).
Plasma or serum levels of albumin are frequently used to assess nutritional status.
Hyperalbuminemia is of little diagnostic significance except in the case of dehydration. When plasma or serum albumin values fall below 2.0 g/dL, edema is usually present.
Cautions Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances
Albumin values determined by the bromcresol green method may not be identical to the albumin values determined by electrophoresis.
Reference Values Describes reference intervals and additional information for interpretation of test results. May include intervals based on age and sex when appropriate. Intervals are Mayo-derived, unless otherwise designated. If an interpretive report is provided, the reference value field will state this.
> or =12 months: 3.5-5.0 g/dL
Reference values have not been established for patients who are <12 months of age.
Clinical References Provides recommendations for further in-depth reading of a clinical nature
1. Tietz Textbook of Clinical Chemistry. Edited by CA Burtis, ER Ashwood. Philadelphia, WB Saunders Company, 1994
2. Peters T, Jr: Serum albumin. In The Plasma Proteins. Second edition. Vol 1. Edited by F Putnam, New York, Academic Press, 1975