Medyra
Immune System

Reviewed: 13. Juli 2026

IgM Immunoglobulin M (IgM)

Unit: g/l

Quick Explanation

IgM is the first antibody class formed with a new infection, and therefore usually indicates an acute or recently occurred infection. The value is often assessed together with IgG to distinguish acute from past infections.

📊 Reference Values

Normal
0.4 – 2.3 g/l
Elevated
above 2.3 g/l

ℹ️ Reference ranges may vary slightly between laboratories. Always compare your value with the reference range from your own lab report.

🔍 Possible Causes

Value too high — possible causes

  • ·Acute infection
  • ·Certain autoimmune diseases
  • ·Certain blood disorders (e.g. Waldenström's macroglobulinemia)

Value too low — possible causes

  • ·Congenital or acquired immune deficiency

This list shows possible causes — not a diagnosis. Only your doctor can correctly interpret your result.

🩺 Questions for Your Doctor

  • Does my IgM value indicate an acute infection?
  • Should IgG also be measured?

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Medical Disclaimer

The content on this page is for general information only and does not replace professional medical advice, diagnosis, or treatment. Always consult your doctor or pharmacist for health-related questions. Lab values should always be assessed in the context of your personal medical history.

IgM explained | Medyra | Medyra AI