Serum albumin

Albumin is a protein produced by the liver and the most abundant protein in blood. The test measures its serum concentration and helps assess liver and kidney function, swelling and long-term illness, and interpret other findings such as calcium.

Who is this test for

• people undergoing liver function assessment, particularly with chronic liver disease, alongside other liver tests;
• people with swelling of the legs, face or abdomen;
• people with suspected kidney disease causing urinary protein loss, for example when proteins are found in urine;
• people with prolonged diarrhoea, poor absorption or unintentional weight loss;
• people whose doctor is interpreting total blood calcium, because much calcium is carried bound to albumin;
• people with severe or long-term illness, for monitoring.

What albumin is and what it shows

Albumin accounts for more than half of all blood proteins. It keeps fluid inside blood vessels; when there is too little, fluid enters tissues and swelling develops. It also transports calcium, bilirubin, fatty acids, certain hormones and medicines through blood.

Albumin levels depend on how much the liver produces, how much is lost through urine, intestines or damaged skin, and fluid distribution in the body. Albumin is also a negative acute-phase reactant: during inflammation, infection, after surgery or injury, the liver produces less, so it falls regardless of diet.

Panels including this test

Test Serum albumin is also included in this panel.

Free testosterone paneltotal testosterone, SHBG, serum albumin37.00€Details ›

All panels including Serum albumin (2) ›

Preparation and sample

Albumin is measured in venous blood. Fasting is not required for this test alone, but if other tests such as glucose or lipids are performed the same day, come fasting in the morning. Tell your doctor about recent infection, surgery or intravenous fluids.

How results are interpreted

Albumin is expressed in g/L. In adults, the reference interval is usually approximately 35 to 52 g/L but depends on age and method and is printed on your report. One value rarely establishes a diagnosis alone: a doctor interprets it alongside symptoms, total proteins, liver tests, kidney findings and inflammatory markers.

Low albumin

• Inflammation and acute illness are the most common reasons for mildly low albumin, for example during infection, after surgery or with chronic inflammatory disease. In these cases, albumin is considered alongside CRP.
• Liver disease: in advanced disease such as cirrhosis, the liver produces less albumin.
• Kidney disease: in nephrotic syndrome and some other kidney disorders, albumin is lost in urine. A doctor then requests urinalysis, urine proteins and creatinine.
• Loss through the intestines or skin: in certain intestinal diseases, extensive burns and severe skin diseases.
• Severe malnutrition and poor absorption, for example in untreated coeliac disease.
• Blood dilution: during pregnancy, heart failure or after large amounts of intravenous fluids.

Albumin is not a reliable nutritional marker. In its 2021 position paper, the American Society for Parenteral and Enteral Nutrition (ASPEN) states that low albumin primarily reflects inflammation and disease severity, not dietary protein deficiency. With inflammation, albumin may be low even in someone who eats well.

High albumin

High albumin almost always results from dehydration, for example after diarrhoea, vomiting or insufficient fluid intake. Less fluid in the blood makes proteins more concentrated. Once fluids are replaced, the value returns within range. A protein-rich diet or supplements do not increase albumin.

How to arrange testing

You can come for blood collection without an appointment or referral at one of our branches throughout Croatia (listed on the Contactpage). Prices for all tests and panels are listed in the service price list. Take the result to the doctor who recommended the test.

Frequently asked questions

What is the difference between serum albumin and urine microalbumin?

Serum albumin shows how much albumin is in the blood. Urine microalbumin is a different test: it detects small amounts of albumin passing through the kidneys and is used for early detection of kidney damage, for example in diabetes or high blood pressure. Blood albumin can remain entirely normal.

What does low blood albumin mean?

Most often inflammation or acute illness; with markedly low values, also liver disease or protein loss through the kidneys or intestines. A doctor assesses the cause alongside other findings and may also suggest protein electrophoresis.

Can I raise albumin through diet?

If albumin is low due to inflammation or disease, eating more protein will not increase it by itself. The level improves when the cause is treated. Nutrition matters in true malnutrition, as assessed by a doctor.