Anti-neutrophil cytoplasmic antibody (ANCA) is an autoantibody present in the blood. After neutrophils are stimulated by antigen, α-particles in the cytosol release protease-3, myeloperoxidase and Leukocyte antigen production, which stimulates the body to produce ANCA, has been confirmed to be a group of serum markers of systemic necrotizing vasculitis. It is of great significance for the diagnosis, classification, differential diagnosis and prognosis evaluation of vasculitis.

Basic Information

Specialist classification: cardiovascular examination classification: blood examination

Applicable gender: whether men and women apply fasting: fasting

Analysis results:

Below normal:

Normal value:
no

Above normal:

negative:
normal.

Positive:
abnormal.

Tips: After 8 pm on the day before the medical examination, you should start fasting for 12 hours. Normal value

Normal human serum is negative.

Clinical significance

Abnormal results ANCA was detected by classical indirect immunofluorescence technique (IIF). The positive fluorescent staining model was divided into two cytoplasmic types (cANCA) and perinuclear type (pANCA). A special fluorescence spectrum has recently been reported as atypical ANCA (xANCA). ANCA is often associated with the activity of the disease, and the titer decreases or disappears during the remission period.

The cANCA antigen is mainly protease-3 (PR3-proteinase). cANCA is mainly found in Wegener's granulomatosis (positive rate accounts for 80% and is associated with disease duration, severity and mobility). A specific antibody to Wegener (WG) granulomatosis. C-ANCA has an affinity for the respiratory tract, causing upper and lower respiratory tract necrosis and granuloma formation. C-ANCA positivity can also be seen in a few microscopic polyarteritis (MPA), Churg-Strauss syndrome (CSS), nodular polyarteritis (PAN), a few giant cell arteritis, allergic purpura, white blood cell-breaking skin Vasculitis and Behcet's disease.

The pANCA antigen is mainly myeloperoxidase (MPO). pANCA is not as diagnostic specific as cANCA. Positive pANC is mainly seen in idiopathic necrotizing crescentic glomerulonephritis (NCGN) and microscopic polyarteritis (MPA). Also found in Churg-Strauss syndrome (CSS), nodular polyarteritis (PAN), SLE, RA, SS, SSc. The positive rates of pANCA and cANCA were almost the same in NCGN and MPA. Relatively speaking, patients with pANCA have severe vasculitis lesions and often have multiple systemic damage.

Atypical ANCA (xANCA) It represents a mixture of pANCA and cANCA. Positive for ulcerative colitis, c and chronic inflammatory diseases.

Need to check the skin bleeding spots, bleeding spots, symptoms such as hematuria, proteinuria and other symptoms.

Positive results may be diseases: benign lymphocytic vasculitis and granulomatous disease, nodular polyarteritis, Wegener's granulomatous scleritis, juvenile rheumatoid arthritis, allergic vasculitis and granulomatosis, erythema Lupus, benign lymphocytic vasculitis and granulomatosis, Terrien corneal marginal degeneration, Wegner granulomatosis associated with uveitis considerations

Inappropriate people: generally no special population.

Contraindications before the examination: After 8 pm on the day before the medical examination, fasting should be started for 12 hours to avoid affecting the test results.

Requirements for examination: neutrophil cytoplasmic toxic particles indicate neutrophil damage, severe inflammatory response, severe disease, more common in patients with blood diseases, extensive burns and severe infections. Patients should pay attention to the doctor to do a good job.

Inspection process

Indirect immunofluorescence: fluorescein is labeled on the corresponding [de] antibody and directly reacts with the corresponding antigen.

In the first step, an unknown unlabeled [de] antibody (sample to be tested) is added to a known antigen sample, and incubated at 37 ° C for 30 min in a wet box to fully bind the antigen antibody, followed by washing to remove unbound [de] antibody. .

In the second step, a fluorescently labeled [de]antiglobulin antibody or an anti-IgG, IgM antibody is added. If an antigen-antibody reaction occurs in the first step, the labeled [de] anti-globulin antibody is further bound to the bound antigen [de] antibody, thereby identifying an unknown antibody.

Not suitable for the crowd

There are no special taboos.

Adverse reactions and risks

There are no related complications and hazards.