What are the four items of ANCA?

The four ANCA items are used to examine the indicators of diseases related to anti-neutrophil cytoplasmic antibodies, and are mainly used to diagnose and evaluate specific autoimmune diseases, such as vasculitis, lupus, etc. The main detection contents include PR3-ANCA and MPO-ANCA, which can be used to determine the type and activity of the disease, thereby assisting doctors in formulating targeted treatment plans.

1. Purpose of the four ANCA tests

ANCA (anti-neutrophil cytoplasmic antibodies) is an important marker of autoimmune diseases and consists of two major categories of indicators: proteinase 3 antibodies (PR3-ANCA) and myeloperoxidase antibodies (MPO-ANCA). This test is mainly used for early diagnosis and monitoring of autoimmune diseases, especially small vessel inflammation, such as microscopic polyangiitis (MPA) and granulomatosis with polyangiitis (GPA). PR3-ANCA is mostly closely related to GPA, while MPO-ANCA is common in MPA and other forms of vasculitis. By detecting these two indicators, it is possible to determine whether the disease involves abnormalities in the immune system and to assess the activity of the disease.

2. Check the indications

The four ANCA tests are usually applicable to the following clinical situations:

- Patients suspected of systemic vasculitis: often experience unexplained fever, joint swelling and pain, skin purpura, nasal ulcers, etc.

- Recurrent immune system-related symptoms such as cough, wheezing, shortness of breath with blood in sputum, and possible progression to renal failure; this test should be considered when serious infection has been ruled out.

- Screening for other autoimmune diseases: When there is a possibility of synergy between rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE), ANCA should be used to screen for the range of diseases.

3. How to carry out relevant treatment

After the ANCA test results are clear, targeted treatments can be taken, including drug therapy, regular follow-up testing, and lifestyle management:

-Medication

-Glucocorticoids: such as prednisone, can quickly reduce inflammatory responses and are often used to control acute attacks of the disease.

-Immunosuppressants: such as cyclophosphamide, are used to suppress an overactive immune system, but be aware of the side effects of long-term use.

- Biological agents: such as rituximab, are mainly used to treat patients who are ineffective with traditional drugs or have severe diseases.

- Follow-up review

According to the disease activity, ANCA indicators (MPO and PR3) should be reviewed regularly to evaluate the treatment effect and adjust the medication regimen in time.

- Lifestyle Adjustments

- Low-salt and low-fat diet to reduce cardiovascular risk;

-Avoid sources of infection and strengthen immunity, such as receiving routine vaccinations;

- Quit smoking and limit alcohol consumption to reduce stress on the respiratory system and kidneys.

4. Inspection precautions

The four ANCA tests are blood tests, usually performed by drawing blood. Before the test, it is recommended to fast and avoid strenuous exercise. Accurate test results also need to be combined with the patient's symptoms and signs and other auxiliary test results (such as urine routine, renal function tests or lung imaging tests) to rule out the possibility of misdiagnosis.

The four ANCA tests are of great significance in the diagnosis and management of autoimmune diseases. If you experience similar symptoms, you should seek medical attention as soon as possible for relevant examinations and follow-up diagnosis, so that intervention measures can be taken early to effectively control the progression of the disease.