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Ancaabseracnc

Published: August 9, 2026Updated: August 17, 2026

A blood test that detects antibodies targeting neutrophils, used to diagnose certain types of blood vessel inflammation (vasculitis).

Quick summary

{"ANCA test helps diagnose autoimmune vasculitis conditions","It measures antibodies that attack white blood cells called neutrophils","Results help distinguish between different types of vasculitis","The test is performed on a blood sample","Results are interpreted alongside clinical symptoms"}

Medically reviewed by WellAlly Editorial TeamLast reviewed August 17, 2026Editorial policy

Key facts at a glance

LOINC
5128-4
Short code
ANCA
Synonyms
ANCA Ab Ser-aCnc
Category
chemistry
Sample
serum
Container
Serum separator tube (SST) or red-top tube
Units
N/A
Ref low
0
Ref high
1
Critical range
0.5 N/A – —
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Method
Enzyme-Linked Immunosorbent Assay (ELISA) with confirmation by indirect immunofluorescence assay (IFA)
CPT
86255
SNOMED
436571000124102
Specimen volume
1-2 mL of serum
Stability
Room temperature: 8 hours; Refrigerated (2-8°C): 7 days; Frozen (-20°C or below): 30 days. Avoid repeated freeze-thaw cycles.
Hemolysis max
100
Lipemia max
100
Icterus max
50
TAT
24–72 hours
Order
routine

What is this test?

The Neutrophil Cytoplasmic Antibody (ANCA) test is a blood test that detects specific antibodies in your blood. These antibodies target neutrophils, a type of white blood cell that helps fight infections. When present, these antibodies can indicate an autoimmune disorder where the immune system mistakenly attacks the body's own blood vessels.

Why is this test performed?

This test is primarily ordered to help diagnose and monitor certain types of vasculitis, including Granulomatosis with Polyangiitis (GPA), Microscopic Polyangiitis (MPA), and Eosinophilic Granulomatosis with Polyangiitis (EGPA). It may also be used to differentiate between these conditions and other diseases with similar symptoms.

How is the test done?

A healthcare professional will draw a blood sample from a vein in your arm. The blood is then sent to a laboratory where it is analyzed for the presence of ANCA antibodies. You may need to fast or avoid certain medications before the test, so follow your doctor's instructions.

Understanding your results

Results are reported as positive or negative, and may include the pattern of staining (c-ANCA or p-ANCA). A positive result suggests the presence of vasculitis, but your doctor will interpret the results along with your symptoms, physical examination, and other tests for an accurate diagnosis.

Reference range

Negative: < 1:20 titer or < 20 Units; results reported as positive or negative depending on assay format. Reference range varies by laboratory and methodology used.N/A

Specimen: serum

No fasting required. Patients should inform their healthcare provider of any medications, as immunosuppressants may affect antibody titers.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

◆Associated findings1

Frequently asked questions

Do I need to prepare for the ANCA test?
You may need to fast for several hours before the test. Inform your doctor about any medications you're taking, as some drugs can affect the test results. Follow your healthcare provider's specific instructions.
What does a positive ANCA result mean?
A positive ANCA result suggests you may have an autoimmune vasculitis condition. However, this alone does not confirm a diagnosis. Your doctor will evaluate the results alongside your symptoms, physical exam, and other laboratory tests to make an accurate diagnosis.
Is the ANCA test painful?
You may feel a brief sting or pain when the needle is inserted to draw blood. This is typically well-tolerated, and the procedure only takes a few minutes.
How long does it take to get results?
Results are usually available within a few days to a week, depending on the laboratory. Your healthcare provider will contact you with the results or discuss them at your follow-up appointment.
Can ANCA be positive in other conditions?
Yes, ANCA can sometimes be positive in other conditions such as inflammatory bowel disease, rheumatoid arthritis, or certain infections. This is why the test results must be interpreted in context of your overall clinical picture.
  1. 1
    Mayo Clinic - ANCA testSource
  2. 2
    MedlinePlus - ANCASource
  3. 3
    Arthritis Foundation - ANCA VasculitisSource

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.

Medical Disclaimer

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 17, 2026. · Read our editorial policy