What is a serum Albumin test?
You need a proper balance of albumin to keep fluid from leaking out of blood vessels (= oncotic pressure). It also carries vital nutrients and hormones. Albumin also gives your body the proteins it needs to keep growing and repairing tissue.
A serum albumin test is a simple blood test that measures the amount of albumin in your blood. Having surgery, getting burned, or having an open wound raises your chances of having a low albumin level.
What Is Albumin?
Albumin is the most common protein found in the blood. It represents half (~50%) of the total protein content (reference range: 3.8 g/dL to 4.8 g/dL) of plasma in healthy human patients.
Albumin is synthesized (= produced) by liver hepatocytes (= the major cells in the liver). Very little albumin is stored in the liver, and most of it gets rapidly excreted into the bloodstream.
Albumin has two main functions:
1. Maintenance (modulation) of appropriate oncotic pressure in the vascular system.
Albumin is responsible for much of the colloidal osmotic pressure of the blood, and hence is a very important factor in regulating the exchange of water between the plasma and the interstitial compartment, which is the space between the cells. Due to the hydrostatic pressure, water is forced through the walls of the capillaries in the tissue space. This flow of water is continuous until the osmotic pull of protein, in this case albumin molecules, causes it to stop. An abnormal deficiency of albumin can lead to water passing from the bloodstream into the tissues (edema).
2. Transporter of endogenous and exogenous (i.e. drugs) ligands.
Albumin serves as a transport protein carrying large organic anions, those such as fatty acids, hormones (cortisol and thyroxine when their specific binding globulins are saturated), bilirubin and many drugs. Severe liver disease can result in hypoalbuminemia (hypo = below, beneath), which leads to fewer available binding sites for exogenous drugs. This results in larger amounts of unbound exogenous drugs, which can lead to increased drug sensitivity. This sensitivity manifests when patients have serum albumin concentrations lower than 2.5 g/dL.
Normal range for Albumin levels:
→ The normal range is 3.8 - 4.8 g/dL (38 to 48 g/L).
Normal value ranges may vary slightly among different laboratories. Some labs use different measurements or test different samples.
Yuwen P, Chen W, Lv H, Feng C, Li Y, Zhang T, Hu P, Guo J, Tian Y, Liu L, Sun J, Zhang Y. Albumin and surgical site infection risk in orthopaedics: a meta-analysis. BMC Surg. 2017 Jan 16;17(1):7. doi: 10.1186/s12893-016-0186-6. PMID: 28093079; PMCID: PMC5238522.
Anderson CF, Wochos DN. The utility of serum albumin values in the nutritional assessment of hospitalized patients. Mayo Clin Proc. 1982 Mar;57(3):181-4. PMID: 6801397.
Shapiro M, Rhodes JB, Beyer PL. Malnutrition. Recognition and correction by enteral nutrition. J Kans Med Soc. 1983 Jun;84(6):341-5, 356. PMID: 6409975.
Martin Kroll, Tietz Textbook of Clinical Chemistry, Third Edition. Carl A. Burtis and Edward R. Ashwood, eds. Philadelphia, PA: WB Saunders, 1998, 1917 pp., ISBN 0-7216-5610-2., Clinical Chemistry, Volume 45, Issue 6, 1 June 1999, Pages 913–914, https://doi.org/10.1093/clinchem/45.6.913
Moman RN, Gupta N, Varacallo M. Physiology, Albumin. [Updated 2022 Dec 26]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2023 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK459198/
Conditions associated with low levels of albumin are as follows:
- Ascites (= a buildup of fluid in your abdomen. It often occurs as a result of cirrhosis, a liver disease.)
- Glomerulonephritis (= inflammation and damage to the filtering part of the kidneys (glomerulus)).
- Liver disease (hepatitis or cirrhosis)
- Malabsorption syndromes (eg, Crohn disease, celiac disease, or Whipple disease)
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.
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.
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 (= TIBC) <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.
In severe malnutrition, albumin has been reported as <2.5 g/dL, total lymphocytes as <800/mm3 and TIBC as <150 μg/dL.
- 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.
- A low albumin level in patients with hepatitis C can be a sign of cirrhosis (advanced liver disease). Albumin levels can go up and down slightly. Very low albumin levels can cause symptoms of edema, or fluid accumulation, in the abdomen (called ascites) or in the leg (called edema).
- A low albumin level can also come from kidney disease, malnutrition, or acute illness.
- A low albumin level causing fluid overload is often treated with diuretic medications, or "water pills."
Potential treatment options:
The best option for treating hypoalbuminemia is to address the underlying cause. So people may need to have a variety of tests to determine why there is not enough albumin in their blood.
Treatment may include:
- blood pressure medication for people with kidney disease or heart failure
- lifestyle changes, particularly avoiding alcohol in people with liver disease
- medications to manage chronic gastrointestinal disease or reduce inflammation in the body
- medications, such as antibiotics, if a person has hypoalbuminemia after a severe burn
- dietary changes to reduce the severity of heart or kidney disease
→ Critically ill patients may require intravenous albumin to raise their levels. It is currently unclear how intravenous administration may benefit other patients.
→ People experiencing hypoalbuminemia due to organ failure may need an organ transplant. People with kidney disease may need dialysis as they await a kidney transplant.
→ People with hypoalbuminemia may need to be hospitalized and monitored until the condition is corrected.
- Higher than normal albumin levels may be a sign of dehydration, which may be caused by severe diarrhea or other conditions. Also look for increase in hemoglobin, hematocrit.
- Higher albumin levels may be caused by acute infections, burns, and stress from surgery or a heart attack.
- Certain medicines can raise your albumin levels. These include insulin, steroids, and hormones.
- If your albumin levels are not in the normal range, it doesn't always mean you have a medical condition that needs treatment. Certain medicines, including steroids, insulin, and hormones, can increase albumin levels.
- Many things may affect your lab test results. These include the method each lab uses to do the test. Even if your test results are different from the normal value, you may not have a problem.
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