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Causes of high and low immunoglobulin M
Medical expert of the article
Last reviewed: 06.07.2025
Since IgM-ATs appear at the first stage of the immune response and are mainly found in the vascular bed, they play an important protective role in bacteremia at the early stages of infection. The multivalence of these antibodies makes them especially active in agglutination and lysis reactions. A decrease in their content indicates a deficiency of humoral immunity, a disruption in the synthesis or increased catabolism of immunoglobulin M, as well as its adsorption on immune complexes during inflammatory processes.
Changes in the concentration of immunoglobulin M in blood serum in various diseases
| Increased concentration | Decreased concentration |
Acute bacterial, fungal, parasitic and viral infections Acute viral hepatitis Autoimmune diseases Cirrhosis Rheumatoid arthritis Systemic lupus erythematosus Endothelioma, osteosarcoma Myeloma disease Waldenstrom's macroglobulinemia Candidiasis, cystic fibrosis Respiratory diseases Monoclonal gammopathy Acute and chronic lymphocytic leukemia |
Physiological hypogammaglobulinemia (in children aged 3-5 months) Congenital hypogammaglobulinemia or agammaglobulinemia Diseases that lead to depletion of the immune system:
Treatment with cytostatics and immunosuppressants, ionizing radiation Chronic viral infection Humoral immunity deficiency |