ANCA-P test is a test that detects anti-neutrophil cytoplasmic antibodies in your blood. Antibodies are proteins that help in fighting against foreign substances. But ANCA as an anti-neutrophil antibody attacks healthy cells of the body and leads to several disorders. An ANCA test is most often used to find out if you have a type of autoimmune vasculitis.

ANCA are of two types that target a specific protein inside white blood cells:

• ANCA-P- A type of anti-neutrophil cytoplasmic antibody that targets a protein called Myeloperoxidase (MPO).
• ANCA-C- The second type of ANCA targets a protein called Proteinase (PR3).

The p-ANCA test can show whether you have one or both types of antibodies and help to diagnose several autoimmune diseases. These immune-mediated diseases cause inflammation, swelling of blood vessels, tissue damage and organ failure and need early detection for treatment.

A p-ANCA test helps detect, diagnose and monitor systemic vasculitis (an autoimmune disorder); also, it helps distinguish between the type of IBD (inflammatory bowel disease), either Crohn's disease or ulcerative colitis.

Along with detection, it's also important to interpret the results of the p-ANCA test carefully. In the case of a negative result, your symptoms are probably not the result of autoimmune vasculitis. But, if your test results are positive, you may have autoimmune disorders.

Consequently, after diagnosing the autoimmune disorders and p-ANAC testing is positive, there is a need for an additional test like a biopsy to confirm the diagnosis. The doctor will consider your signs and symptoms as well as the results of the laboratory tests and other types of tests, including imaging studies, to confirm the diagnosis of auto-immune disorders.

Additionally, the p-ANCA test is also known as the MPO test, where MPO stands for Myeloperoxidase. The p-ANCA test is done if one has a fever, muscle aches and weight loss, impaired kidney or lung function, chronic diarrhoea or abdominal pain.

In several studies, 90% of patients are diagnosed positive with microscopic polyangiitis (MPA) in the p-ANCA test. The p-ANCA test detects a positive result in 40% of the cases of Churg Strauss or Granulomatosis with Polyangiitis.

Other names of the p-ANCA Test

• ACPA test

• ACNA test

• Cytoplasmic antibody test

• Myeloperoxidase antibodies test
• Serum anti-cytoplasmic antibodies test
• Wegener's Disease test

What does the p-ANCA test measure and who is this prescribed for?

The p-ANCA test measures the levels of perinuclear antineutrophil antibodies in the blood. High positivity can affect several health conditions related to the body or damage the body.

Improper functioning of the immune system and the presence of anti-neutrophil antibodies is indicated if a person is experiencing the following conditions:

• Redness, itching, and stiffness in the eyes
• Problems with vision like loss of vision, blurred vision
• Skin rashes or sores
• Running nose
• Shortness or difficulty breathing
• Respiratory problems
• Hearing loss or problems with hearing
• Kidney problems like proteinuria (the presence of protein in the urine)
• Diarrhoea (continues watery passing of stool)
• Mild to severe abdominal pain
• Abdominal cramps
• Fever
• Fatigue

For people with such complaints, amongst other tests, the p-ANCA test is prescribed by the consulting physician.

Some disease conditions for which a p-ANCA test can be prescribed are:

• Rectal bleeding
• Low growth and development in children
• Wegener's granulomatosis
• Kidney diseases
• Microscopic polyangiitis

Following a diagnosis, an immunologist, rheumatologist or physician will initiate treatment for auto-immune disorders. The p-ANCA test may be prescribed every 6 months to monitor and regulate the dosage.

By analyzing the results of the p-ANCA test, your doctor can determine whether to continue the same treatment or modify its dosage. The p-ANCA test applies to males and females, both adults and children.