Albumin, Serum

Albumin, Serum

CPT Test code: 82040

Specimen: Serum (preferred) or plasma
Volume: 1 mL
Minimum Volume: 0.5 mL
Container: Red-top tube, gel-barrier tube, green-top (heparin) tube, or lavender-top (EDTA) tube
Collection: Separate serum or plasma from cells within 45 minutes of collection.
Storage Instructions: Maintain specimen at room temperature.
Causes for Rejection: Fluoride plasma specimen; gross hemolysis; lipemia; improper labeling
Use: Evaluation of nutritional status, blood oncotic pressure; evaluation of renal disease with proteinuria and other chronic diseases.

High albumin may indicate dehydration. Look for increase in hemoglobin, hematocrit in such patients.

Low albumin is found with use of I.V. fluids, rapid hydration, overhydration; cirrhosis, other liver disease, including chronic alcoholism; in pregnancy and with oral contraceptive use; many chronic diseases including the nephrotic syndromes, neoplasia, protein-losing enteropathies (including Crohn’s disease and ulcerative colitis), peptic ulcer, thyroid disease, burns, severe skin disease, prolonged immobilization, heart failure, chronic inflammatory diseases such as the collagen diseases and other chronic catabolic states.

Starvation, malabsorption, or malnutrition: In the absence of I.V. fluid therapy and in patients without liver or renal disease, low albumin may be regarded as an indication of inadequate body protein reserves. It is described as the most common nutrition-related abnormality in patients with infection.1 Serum albumin has a half-life of about 18 to 20 days. Its half-life is decreased in patients with catabolic states: infection and with protein loss through the kidneys (eg, nephrosis), gastrointestinal tract, and skin (eg, burns). Its prognostic application is most useful in patients with weight loss, anorexia, stress, surgical therapy, hemorrhage, and infection. Total iron binding capacity <240 μg/dL1 and/or low transferrin levels would support an impression of inadequate protein reserves. Absolute lymphocyte counts <1500/mm3 may also be seen with protein malnutrition.2 In severe malnutrition, albumin has been reported as <2.5 g/dL, total lymphocytes as <800/mm3 and TIBC as <150 μg/dL.2

Albumin levels ≤2.0-2.5 g/dL may be the cause of edema (eg, nephrotic syndrome, protein-losing enteropathies).

Albumin, prealbumin, and transferrin are regarded as “negative” acute phase reactants (ie, these proteins decrease with acute inflammatory/infectious processes).

Low albumin values are associated with longer hospital stay.1

Additional Information: Twenty-four hour urine collection to measure protein loss is helpful in work-up of some patients with hypoalbuminemia. Other tests useful in assessment of nutritional status include TIBC, transferrin, iron, absolute lymphocyte count, and vitamin B12/folate levels.
Footnotes: 1. Anderson CF, Wochos DN, “The Utility of Serum Albumin Values in the Nutritional Assessment of Hospitalized Patients,” Mayo Clin Proc, 1982, 57(3):181-4. PubMed 6801397

2. Shapiro M, Rhodes JB, Beyer PL, “Malnutrition. Recognition and Correction by Enteral Nutrition,” J Kans Med Soc, 1983, 84(6):341-5, 356.PubMed 6409975

References: Tonks DB, “A Study of the Accuracy and Precision of Clinical Chemistry Determinations in 170 Canadian Laboratories,” Clin Chem, 1963, 9:217-63.PubMed 13985504