Serum Protein Electrophoresis

Serum protein electrophoresis separates blood proteins into several groups, called fractions, and shows whether their relative proportions have changed. A doctor requests it for suspected inflammatory conditions or liver and kidney disease, and particularly to check for a monoclonal protein (M-protein) in the blood. The result alone does not establish a diagnosis but guides further investigation.

Who the test is for

• people with unexplained anaemia, bone pain or fractures, high calcium or kidney damage, when a doctor suspects monoclonal gammopathy or multiple myeloma;
• people with high total protein and low albumin;
• people with an elevated sedimentation rate or frequent infections without a clear cause;
• people with chronic inflammatory and autoimmune diseases or liver disease;
• people losing protein through the kidneys or intestines;
• people with an already detected monoclonal protein, for monitoring at intervals set by a doctor.

What protein electrophoresis is and what it indicates

Blood contains hundreds of different proteins. A total protein test gives only their sum, while electrophoresis separates them and displays a curve with peaks. Alongside the curve, the report lists each fraction as a percentage and often its quantity in g/L.

• Albumin accounts for more than half of blood proteins. Produced in the liver, it keeps fluid within blood vessels and transports hormones, medicines and other substances. Read more in the article on serum albumin.
• Alpha-1 globulins, of which alpha-1-antitrypsin is the most important, rise in inflammation.
• Alpha-2 globulins (haptoglobin, alpha-2-macroglobulin, ceruloplasmin) rise in inflammation and certain kidney diseases.
• Beta globulins include transferrin, which transports iron, part of complement and lipoproteins.
• Gamma globulins are mostly immunoglobulins, or antibodies (IgG, IgA and IgM).

Some laboratories divide the beta fraction into two parts, so the report may show six fractions instead of five.

Preparation and sample

The test uses blood taken from a vein. The laboratory analyses serum, the liquid part of blood remaining after clotting. You do not need to fast for electrophoresis alone, but if glucose, lipids or PT are tested from the same sample, come in the morning after fasting. Tell your doctor about a recent infection because inflammation temporarily changes alpha and gamma fractions.

How protein electrophoresis results are interpreted

Fraction reference ranges depend on the method and are printed on the report. A doctor interprets results alongside total protein, albumin, CRP, blood count and kidney results, because the same pattern can have several causes.

Result pattern	Most common meaning
low albumin, high alpha-1 and alpha-2 fractions	acute inflammation or infection
broadly elevated gamma fraction	chronic inflammation, autoimmune diseases, chronic infections, liver disease
low albumin, high gamma fraction, often merged beta and gamma peaks	liver cirrhosis
low albumin, markedly elevated alpha-2 fraction, low gamma fraction	protein loss in urine, e.g. nephrotic syndrome
low gamma fraction	inherited or acquired antibody deficiency
a narrow, sharp peak, most often in the gamma and less often in the beta region	monoclonal protein (M-protein)

Monoclonal protein (M-protein)

M-protein is an antibody or antibody fragment produced by one group of identical plasma cells. It most often represents monoclonal gammopathy of undetermined significance (MGUS). This affects 3 to 4 % of people over 50, usually causes no symptoms, and most people with it never develop disease. The risk of progression to multiple myeloma or a related condition is approximately 1 % per year or less, so MGUS is monitored regularly.

Less often, M-protein indicates multiple myeloma, Waldenström’s macroglobulinaemia, lymphoma or amyloidosis. After such a result, a doctor, usually a haematologist, therefore requests further tests: immunofixation to identify the M-protein type, serum free light chains, blood count, calcium and creatinine. Assessment is based on all these findings together.

Normal electrophoresis does not exclude every monoclonal disorder. Very small amounts of M-protein and disease producing only light chains may go undetected, so when suspicion is strong a doctor requests other tests alongside electrophoresis.

How to arrange testing

You can have blood taken without an appointment or referral at one of our branches across Croatia (listed on the Contact page). Prices for all tests and panels are available in the service price list. Take the results to the doctor who recommended the test.

Frequently asked questions

Is protein electrophoresis a cancer test?

No. Electrophoresis is not used to detect cancer in healthy people. It may show M-protein, which most often indicates MGUS rather than malignancy. This test does not detect most other tumours, nor do tumour markersreliably detect them.

What does an elevated gamma fraction mean?

A broadly elevated gamma fraction means the body is producing more different antibodies, a common response to chronic inflammation, infection, autoimmune disease or liver disease. A narrow, sharp peak in the gamma region is different: it raises suspicion of M-protein and requires further investigation.

Can a cold affect the result?

Yes. Acute infection raises alpha fractions and may slightly lower albumin. These changes usually disappear after recovery, so a doctor may recommend repeating the test after the infection resolves.

How often is electrophoresis repeated for MGUS?

A doctor sets the interval according to the type and quantity of M-protein and other findings. The first follow-up is usually after several months, with less frequent checks if results remain stable. If new bone pain, fatigue or frequent infections develop between checks, contact your doctor earlier.