An albumin blood test is ordered out to assess the levels of albumin circulating in the blood. It is useful for assessing a person's nutritional status and for identifying possible kidney or liver problems.
Albumin is the protein that is produced in the liver and is present in detectable levels in the blood. This protein is needed to transport hormones and nutrients around the body and to regulate pH. It also helps to maintain the body's osmotic pressure by regulating the amount of water in the blood.
The albumin blood test is usually ordered together with an albumin urine test to help detect any impaired functioning in the kidneys.
Normal albumin levels can vary according to the laboratory where the test is carried out and also according to age.
- 0 to 4 months: 20 to 45 g/L (or 2.0 to 4.5 g/dL)
- 4 months to 16 years: 32 to 52 g/L (or 3.2 to 5.2 g/dL)
- Over 16 years: 35 to 50 g/L (or 3.5 to 5 g/dL)
The normal reference values can vary from lab to lab. Other factors that can influence levels include the patient's age, medication, long-term diarrhea, burns and malnutrition.
What results mean
Albumin can be high or low for a number of reasons:
High albumin levels
High albumin levels in the blood, also referred to as hyperalbuminemia, are usually related to dehydration, which can be caused by diarrhea, for example. This is because dehydration reduces the volume of water in the body, which leads to a higher concentration of albumin in the blood.
Low albumin levels
Low albumin levels, also referred to as hypoalbuminemia, can occur for the following reasons:
- Kidney problems, in which there is increased urine output such as nephrotic syndrome or chronic renal failure.
- Intestinal problems, in which there is a large loss of proteins, including albumin, through the gastrointestinal tract. This can occur in diseases such as ulcerative colitis, Crohn's disease and celiac disease.
- Malnutrition, in which there nutrients are not adequately absorbed or there is a reduced production of albumin.
- Serious illnesses that alter the distribution of albumin between the intra- and extravascular spaces. This can affecting its production in the body and trigger its breakdown.
- Inflammation, such as heart failure, burns, pancreatitis or more delicate surgery;
In addition, low albumin levels in the blood can also be a sign of a liver problem, which can reduce the production of albumin. The doctor may opt to order additional tests to assess liver functioning. Learn more about other liver tests, like the AST and ALT levels, that your doctor may order.
Why it is ordered
The albumin blood test is ordered by the doctor to assess the person's nutritional status and help diagnose kidney and liver diseases. It is often ordered before surgery to check the person's general condition and to assess whether the patient is fit for surgery.
Albumin blood tests are usually ordered with other tests, such as urea, creatinine and total blood protein levels, especially when the patient presents with symptoms of liver disease or symptoms of kidney disease.
How it's done
The albumin blood test does not require fasting and is done by collecting a blood specimen and analyzing it in the laboratory.
Prior to the test, the patient should disclose any medications they are on, especially anabolic steroids, insulin and growth hormone, as these can interfere with the test result and should therefore be taken into account at the time of analysis.