Albumin blood test – biochemical analysis aimed at quantifying the largest protein fraction of blood serum. There are five protein fractions in total: one albumin fraction and four globulins (alpha1-, alpha2-, beta- and gamma-globulins). Albumin in the blood makes up 60% of the total plasma protein, is synthesized in the liver, is the main oncotic component of plasma, serves as the main source of amino acids in it. Determination of albumin in the blood is used for the diagnosis and monitoring of kidney diseases, liver, cancer, the condition of patients with injuries and burns. For analysis, blood is taken from a vein. The deadline for the analysis is one day.
Albumin is a simple globular protein with a molecular weight of 66.3 Da. Albumin synthesis occurs in liver cells. The rate of synthesis is controlled by two factors: protein intake with food and the amount of oncotic pressure. The cleavage of albumin is carried out in lysosomes. Measurement of albumin levels is a component of a laboratory liver function test. Albumin in the blood maintains osmotic pressure, performs a transport function (the transfer of bilirubin, bile acids, vitamins, metal ions, drugs), serves as a protein reserve of the body. There are many methods for determining serum albumin. The photometric method with bromocresol green is unified. There is also an immunological method and electrophoresis (the latter is very time-consuming).
Albumin is the most important indicator by which the overall health of a person is assessed. Albumin blood test is often performed in combination with enzymes that reflect liver function (ALT, AST, GGT). This is due to the fact that albumin is synthesized by liver cells, and when it is damaged, albumin synthesis is disrupted. Therefore, the analysis is indicated for monitoring the condition of patients with liver diseases.
Albumin blood test used in patients with diseases of the gastrointestinal tract (malabsorption syndrome, gastritis, enteritis), as they have a violation of protein absorption. The study is also performed in patients with kidney diseases (nephrotic syndrome, diabetic nephropathy), severe burns and injuries, rheumatic and oncological diseases.
Preparation for analysis and material collection
Blood plasma is used for the analysis. It is recommended to donate blood for albumin in the morning (from 8 to 10 o’clock), strictly on an empty stomach (the last meal no later than 12 hours, a light dinner is recommended the day before). 24 hours before the test, it is necessary to exclude the use of alcohol, as well as the adoption of thermal procedures (bath, sauna). When conducting repeated tests, it is recommended to donate blood at the same time and in the same laboratory – so the results will be as reliable as possible. In addition, it is recommended to take blood before taking medications and other medical manipulations (injections, massage, X-rays).
For this study, blood is taken from a vein using a syringe or a vacuum system. Blood is delivered to the laboratory in specialized transport boxes. Albumin blood test is carried out within an hour, with a heavy workload of the laboratory, the biological material is placed in the refrigerator. Determination of albumin in blood serum is carried out by a unified colorimetric method with bromocresol green. This method is simple, accurate and short-lived. The result is given to the patient or doctor within an hour or at the end of the day (the time of issuing the result depends on the methodology used, equipment and workload of the laboratory).
Normally, in the serum of a healthy person, the albumin content ranges from 35 to 50 g / l, while the values of the indicator are the same for men and women. There are no sharp fluctuations in the albumin content in the blood during a person’s life. Thus, values from 38 to 54 g/l are normal for children, and from 34 to 48 g/l for the elderly. A slight decrease in the albumin content in the blood is typical for pregnant and lactating women. The results of the analysis may be influenced by dietary characteristics (excessive consumption of protein foods leads to an increase in albumin content in the blood), stressful situations, and features of the patient’s constitution. Changes in the albumin content in the blood caused by physiological reasons are insignificant and not persistent.
Raising the level
An increase in the albumin content in the blood is called hyperalbuminemia. There is only relative hyperalbuminemia. Any condition accompanied by water loss (dehydration of the body), in particular, caused by vomiting and diarrhea, can cause an increase in albumin in the blood. Less often, the cause of hyperalbuminemia is intravenous infusions of large doses of albumin solution, hemoconcentration (blood thickening), collagenosis (rheumatoid arthritis, SLE, etc.).
Lowering the level
Hypoalbuminemia is a decrease in the albumin content in the blood. Hypoalbuminemia can be congenital (primary), most often they occur in newborn children with impaired functioning of hepatocytes, and secondary. Secondary hypoalbuminemia develops due to various pathological conditions. A decrease in albumin in the blood can be observed with insufficient intake from food (fasting, an unbalanced diet), as well as with poor absorption in the intestine in various diseases (malabsorption syndrome, enteritis). The reasons for the decrease in albumin in the blood may be chronic liver diseases (hepatitis, cirrhosis, liver failure), in which the synthesis of endogenous albumin is disrupted.
A decrease in albumin is observed in various infectious diseases, sepsis, parasitic lesions, necrotic processes, malignant neoplasms. Increased protein loss is accompanied by diabetic nephropathy and nephrotic syndrome, bleeding, burns and injuries, the formation of transudates and exudates in serous cavities. Also, hypoalbuminemia occurs during pregnancy, taking medications: estrogens, COCs, prednisolone in high doses, azathioprine, valproic acid and others. A decrease in the albumin content below 22-24 g / l is accompanied by the development of pulmonary edema.
Treatment of abnormalities
Determining the concentration of albumin in the blood allows you to detect a large number of diseases, as well as monitor their dynamics. To determine the cause of the change in albumin values, you should consult a doctor who will prescribe an additional examination and make a diagnosis. It is important to note that treatment is not performed on the basis of a single biochemical indicator, a comprehensive examination and determination of the value of albumin in dynamics is necessary.
Treatment, depending on the diagnosis, is prescribed by a gastroenterologist, a nephrologist, a hepatologist, an infectious disease specialist. A change in the albumin content in the blood caused by physiological reasons does not require treatment. It is recommended to get rid of provoking factors: eliminate heavy physical exertion, stress, normalize nutrition.