Understanding Your Laboratory Test: What It Is, How It Is Done, and How to Get Ready
A blood test that detects specific antibodies (IgG) in your blood to help diagnose autoimmune diseases affecting blood vessels.
{"ANCA test checks for antibodies that attack white blood cells called neutrophils","It helps diagnose vasculitis, a condition where blood vessels become inflamed","Results are reported as positive or negative (presence or absence of antibodies)","The test is performed on a blood sample taken from a vein in your arm"}
Key facts at a glance
- LOINC
- 17355-9
- Short code
- ANCAB
- Synonyms
- ANCA IgG Ser Ql
- Category
- chemistry
- Sample
- serum
- Container
- Serum separator tube (SST) or red-top tube
- Units
- N/A
- Critical range
- 0.5 N/A – —
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- Immunofluorescence Assay (IFA) on ethanol- and formalin-fixed neutrophils
- CPT
- 86255
- SNOMED
- 40669008
- Specimen volume
- 1 mL serum (minimum 0.5 mL)
- 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
This test gives your healthcare provider important information about your health. It may be used to screen for a medical condition, help confirm a diagnosis, monitor an ongoing problem, or check how well a treatment is working. Your provider will explain what the test measures and why it is recommended for you.
The Neutrophil Cytoplasmic Antibody (ANCA) test is a blood test that detects the presence of IgG antibodies directed against proteins in neutrophils (a type of white blood cell). These antibodies are called anti-neutrophil cytoplasmic antibodies. The test can identify whether these antibodies are present in your bloodstream, which helps doctors determine if you have certain autoimmune conditions.
The test is usually performed in a clinic, hospital, or laboratory by a trained member of your care team. Depending on the type of test, it may involve a small blood sample drawn from a vein in your arm, a urine or saliva sample, a swab, or an imaging procedure. Most tests take only a few minutes, and you can usually return to your normal activities right afterward.
A healthcare professional will draw a small sample of blood from a vein in your arm using a needle. The blood sample is then sent to a laboratory where it is analyzed to detect the presence or absence of ANCA antibodies. You may experience slight discomfort or bruising at the needle site, but the procedure is generally quick and safe.
In many cases little or no preparation is needed, but some tests have specific requirements. You may be asked to fast for a certain number of hours, avoid certain foods or medications, or drink extra water before your appointment. Tell your provider about all medicines, supplements, and allergies you have, and follow the instructions you are given so your results are as accurate as possible.
No special preparation is typically required for the ANCA test. You can eat and drink normally before the test. However, it is important to inform your doctor about any medications, supplements, or health conditions you have, as certain drugs or infections may affect test results.
Reference range
Negative: No neutrophil cytoplasmic IgG antibodies detected. Positive results reported as titer with cytoplasmic (c-ANCA), perinuclear (p-ANCA), or atypical pattern.N/A
No fasting required. Patients should inform their healthcare provider of any current medications, particularly immunosuppressants, as therapy may affect antibody titers.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
◆Associated findings1
Frequently asked questions
What does a positive ANCA result mean?
What does a negative ANCA result mean?
Is the ANCA test painful?
How long does it take to get results?
Sources
- 1Mayo Clinic - ANCA testSource
- 2
- 3Lab Tests Online - ANCASource
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 17, 2026. · Read our editorial policy