LounaLab service will close June 18th. As of today, products can no longer be purchased there.

All purchased appointments and test results are safe and are available here until the stated date, then transferred to the current SYNLAB service. For more details see the news or contact our representative.

Immunoglobulin A

S -IgA

Immunoglobulins or antibodies are proteins produced by the cells of the body’s immune system. Antibodies attach to structures that are alien to the body, such as bacteria and viruses, and help the immune system to destroy the intruders. There are five categories of immunoglobulin: A, G, M, E and D.

Antibodies of immunoglobulin category A (IgA) are present specifically on the linings of the respiratory tract and gut, where they protect the body from respiratory infections and infections of the gastrointestinal duct. The level of IgA antibodies can be measured from the bloodstream.

When should IgA be measured?

The ability to produce IgA can be inherently absent. This inherited condition is found in 1:400–1:600 Finns. IgA deficiency can predispose to infections and blood transfusion reactions.

IgA concentration can be elevated in liver cirrhosis, autoimmune diseases and chronic infections. The test is a good idea in connection with recurring infections (especially in the respiratory tract), constipation, stomach ache, weight loss and diarrhoea.

What does the IgA test measure?

The test measures the IgA concentration in the blood. IgA accounts for approximately 15 per cent of the antibodies in the blood. IgA is also present in saliva, tears, respiratory tract and stomach secretions, faeces and breastmilk. The test an therefore detect inherited IgA deficiency. The test shows if the immune system is affected by a condition. Immunoglobulin testing does not indicate a specific disease, but the value can suggest a disease in the body.

Normally, the result is: Reference values:

  • Women: 0,5–4,0 g/l
  • Men: 0,9–4,8 g/l

Please contact your physician or other healthcare professional if you suspect an illness or need help interpreting the results.

The reference values of this examination have changed 11.10.2021. You will find your own result's reference values from My LOUNA in touch with the graph. Read more about defining reference values.

Elevated IgA values are typically seen in the following situations:

  • Acute and chronic infections
  • Autoimmune diseases, such as rheumatoid arthritis
  • Liver damage, or cirrhosis
  • Chronic inflammation
  • Inherited immune system disorder known as the Wiskott-Aldrich syndrome
  • Infection in a newborn during pregnancy, such as in connection with congenital syphilis or rubella

Decreased and negative IgA values can occur in the following situations:

  • Inherited IgA deficiency
  • In connection with the use of certain medicinal products (such as phenytoin, carbamazepine, immunosuppressants)
  • Kidney failure
  • Diabetes
  • Burns


Fasting is not required

This examination does not require fasting