Long-term treatment results and the immunoglobulin G subclass distribution patterns of proteinase-3-antineutrophil cytoplasm antibody (ANCA) and myeloperoxidase-ANCA in ANCA-associated vasculitis.
OBJECTIVE
Small vessel vasculitis associated with antibodies to neutrophil cytoplasm antigens has been denominated antineutrophil cytoplasm antibody (ANCA)-associated vasculitis (AAV).


METHODS
Ninety-eight patients with various forms of AAV with renal involvement were studied retrospectively with regard to treatment, side-effects and outcome. The immunoglobulin G (IgG) subclass distribution patterns in serum were determined in 51 patients with nephelometry and those of anti-proteinase-3 (PR3) and anti-myeloperoxidase (MPO) in 44 patients by enzyme-linked immunosorbent assay.


RESULTS
Fifty-nine patients with a mean age of 63 years were given treatment with intermittent intravenous regimens of cyclophosphamide and continuous corticosteroids, whereas 39 patients with a mean age of 58 years were given continuous oral treatment. Malignancy, mainly due to skin tumours, was more common in AAV than in the general population. The total IgG subclass distribution pattern was asymmetric. The response to PR3 was of IgG(1), IgG(3) and IgG(4) isotypes, while IgG(1) and IgG(3) predominated in the response to MPO.


CONCLUSIONS
The aberrant IgG subclass distribution pattern detected in the autoantibodies may be of importance in the pathogenesis of AAV.
Almroth
Gabriel
G
Departments of Nephrology, University Hospital, Linköping, Sweden. gabriel.almroth@lio.se
Berlin
Gosta
G
Andersson
Bengt
B
Hahn-Zoric
Mirjana
M
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019268:Antibodies, Antineutrophil Cytoplasmic / Q000276:immunology*; D003520:Cyclophosphamide / Q000008:administration & dosage; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood*; D007155:Immunologic Factors / Q000276:immunology*; D007166:Immunosuppressive Agents / Q000008:administration & dosage; D008297:Male; D008875:Middle Aged; D053146:Myeloblastin / Q000276:immunology; D009195:Peroxidase / Q000276:immunology; D010951:Plasma Exchange; D012074:Remission Induction; D016896:Treatment Outcome; D014657:Vasculitis / Q000276:immunology* / Q000401:mortality
D019268:Antibodies, Antineutrophil Cytoplasmic; D007074:Immunoglobulin G; D007155:Immunologic Factors; D007166:Immunosuppressive Agents; D003520:Cyclophosphamide; D009195:Peroxidase; D053146:Myeloblastin