Immunoglobulin M (IgM)

Immunoglobulin M (IgM) Is a key antibody that is produced during the primary immune response. IgM has a pentameric structure - 5 IgM molecules are linked by a binding oligopeptide. Rheumatoid factor (in most cases) and ABO system, blood group isoagglutinins (α and β) belong to the IgM class.

IgM is a type of antibody that is initially produced during an immune response and a first-class immunoglobulin that is synthesized by the fetus or newborn. IgM does not cross the placenta. For these reasons, the identification of specific IgM antibodies is useful in assessing the stage of infection (acute infection: IgM antibodies present; chronic infection: IgG antibodies predominant) and the likelihood of congenital infection (if IgM antibodies are present - newborn is infected).

Hyper-IgM immunodeficiency syndrome is characterized by the absence of serum IgG and IgA, which is associated with a sharp increase in IgM.

Macroglobulins produced during Waldenstrom's disease also belong to the IgM class.

Elevated IgM levels are observed in various infectious or inflammatory diseases. Its level is usually elevated also during primary biliary cirrhosis. Decreases are observed in congenital or acquired hypogammaglobulinemia, which is clinically characterized by recurrent infections.

When should I get tested for immunoglobulin M (IgM)?

• Assessment of humoral immunity;
• Diagnosis and monitoring of Waldenstrom macroglobulinemia;
• Assess the likelihood of intrauterine infection.

How to prepare for the test?

The test should be performed on an empty stomach.

Research material

Venous blood

Possible interpretation of the results

Immunoglobulin M concentration increases:

• Waldenstrom disease;
• Liver disease, especially primitive biliary cirrhosis;
• Chronic infections;
• Trypanosomiasis;
• Malaria;
• Systemic lupus erythematosus;
• Rheumatoid arthritis;
• Dysgammaglobulinemia (some patients).

Immunoglobulin M concentration decreases:

• Current syndromes of protein loss;
• Non-IgM myeloma;
• Agammaglobulinemia;
• Lymphoid aplasia;
• Dysgammaglobulinemia;
• Chronic lymphocytic leukemia;
• In infants and early childhood.

Resources

https://www.synevo.ro/shop/imunoglobulina-igm/