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Immunoglobulin M (IgM)

What Is Immunoglobulin M (IgM)?
Immunoglobulin M (IgM) is a type of antibody produced by plasma cells as part of the body’s early immune response to infection. It is the first antibody to appear when the immune system detects a new pathogen, making it a key marker for recent or active infections.

Role of IgM in the Immune System
IgM antibodies are larger in size compared to other antibodies and are primarily found in the blood and lymphatic fluid. They are highly effective at binding to and neutralising bacteria and viruses. IgM also activates the complement system—a group of proteins that help eliminate pathogens from the body.

Diagnostic Importance of IgM Antibody Testing
IgM testing is commonly used to detect acute or recent infections, including viral and bacterial illnesses. Elevated levels of IgM in the blood usually indicate a current or very recent infection, while lower levels may suggest recovery.

Limitations and Complementary Testing
Although high IgM levels may signal an active infection, these antibodies can remain in the bloodstream for weeks or months after recovery. Therefore, IgM tests are often used in combination with IgG tests or viral antigen tests to confirm the stage of infection and ensure accurate diagnosis.

Private IgM Antibody Testing in Slough
Individuals in Slough, Windsor, Maidenhead, and surrounding Berkshire areas can access private IgM antibody testing to assess recent infections and monitor immune response. This test is valuable for early detection and is frequently used in both routine diagnostics and specialist infectious disease assessments.

There is an additional £20 phlebotomy fee for every donation.