Myeloperoxidase IgG Antibodies, Serum or Plasma
This test looks for IgG antibodies directed against myeloperoxidase (MPO), an enzyme found in certain white blood cells. These antibodies can be a marker of certain autoimmune conditions affecting small blood vessels.
["An MPO IgG antibody result is interpreted alongside your symptoms and other tests, and it is not a diagnosis on its own."]
Key facts at a glance
- LOINC
- 108860-8
- Short code
- Myeloperoxidase IgG Msmt SerPl
- Synonyms
- Myeloperoxidase IgG Msmt SerPl
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- CPT
- 82784
- Specimen volume
- 5 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 4–24 hours
- Order
- routine
What Is Being Measured
Myeloperoxidase (MPO) is an enzyme stored in a type of white blood cell called neutrophils. This test measures IgG-class antibodies that bind to MPO. The specimen is serum or plasma, and the result is reported from an immunoassay method.
Why Your Clinician May Order It
This test is often ordered when an autoimmune inflammation of small blood vessels (vasculitis) is suspected, or to help monitor a known condition. It may be part of a panel that also includes other antibody tests.
How the Test Is Done
A blood sample is collected from a vein, usually in your arm, and sent to the laboratory. There is no special preparation required unless your clinician gives other instructions.
How to Understand Your Result
Results are usually reported as positive, negative, or with a numeric level, depending on the laboratory. A positive result does not by itself mean you have a disease, and a negative result does not always rule one out. Your clinician interprets the result together with your symptoms, physical exam, and other laboratory findings.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
MPO IgG antibodies are associated with certain forms of small-vessel vasculitis and can also appear in other inflammatory or autoimmune conditions, and sometimes at low levels in people without disease. Because of this, the test is used as one piece of a broader clinical picture rather than as a stand-alone diagnosis.
Short name
MPO IgG Antibody
Frequently asked questions
Does a positive MPO antibody result mean I have vasculitis?
Do I need to fast before this test?
Can the result change over time?
Sources
- 1
- 2Lab Tests OnlineSource
- 3
Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy