Abstract:

Objective：To study the value of ANCA in the detection of systemic lupus erythematosus disease activity. Methods：The
serum of 53 patients was tested by indirect immunofluorescence（IIF）, and then the specific target antigen protein 3（PR3）and
myeloperoxidase（MPO）in sera of patients with ANCA were detected by enzyme-linked immunosorbent assay（ELASA）. Laboratory
indexes related to the disease activity of SLE patients were detected. Results：ANCA were detected in 21 patients with SLE: the
positive rate was 39.6%, 20 had pANCA and one Cytoplasm antibody（cANCA）. Target antigen was neither MPO nor PR3. Compared
with ANCA negative group, there was a statistically significant difference in regard to the SLE disease activity in ANCA positive group
（P<0.01）. And the anti- dsDNA antibody was positive, complement（C3, C4） decreased, ESR increased and renal injury was
significantly higher in the positive group than in the negative group. So the result was statistically significant（P<0.05）. Conclusion：
ANCA positive in the activity of SLE disease has a certain value and can be used as one of the indicators to determine the activity of
the disease.

Key words: antineutrophil cytoplasmic antibody, Systemic Lupus Erythematosus, activity