Incidence, target antigens, and clinical implications of antineutrophil cytoplasmic antibodies in rheumatoid arthritis.
OBJECTIVE
To determine the incidence of antineutrophil cytoplasmic antibodies (ANCA) in rheumatoid arthritis (RA), to detect the target antigens of ANCA, and to compare clinical and laboratory data of ANCA+ with ANCA- patients with RA.


METHODS
385 sera of patients with RA were screened for ANCA by indirect immunofluorescence. ANCA+ sera were further analyzed for target antigens by ELISA: The ANCA+ patients were compared to randomly selected ANCA- patients with RA with respect to serological and radiological variables and extraarticular involvement.


RESULTS
ANCA were found in 16% of patients with RA (61/385 sera). All sera showed a perinuclear (pANCA) pattern. Antibodies directed against proteinase 3 were not observed. The analysis of ANCA+ and ANCA- patients revealed that the pANCA+ group exhibited significantly higher serological markers of inflammation (p < 0.005) and a higher incidence of rheumatoid factor (p < 0.005). Furthermore, vasculitic involvement was found at a higher frequency (p < 0.05) in the pANCA+ group. Five patients in the pANCA+ group had pulmonary involvement, but none in the pANCA- group.


CONCLUSIONS
pANCA in RA may be a marker for a more aggressive course of disease in respect to serological variables and extraarticular manifestations including rheumatoid vasculitis and lung involvement.
Braun
M G
MG
Poliklinik für Rheumatologie, Universität Lübeck, Germany.
Csernok
E
E
Schmitt
W H
WH
Gross
W L
WL
D000368:Aged; D000937:Antigen-Antibody Reactions / Q000276:immunology*; D001172:Arthritis, Rheumatoid / Q000175:diagnosis / Q000276:immunology*; D001323:Autoantibodies / Q000032:analysis / Q000276:immunology*; D015415:Biomarkers / Q000032:analysis; D002574:Cervical Vertebrae / Q000000981:diagnostic imaging; D018450:Disease Progression; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D019084:Fluorescent Antibody Technique, Indirect; D006801:Humans; D008297:Male; D008875:Middle Aged; D009504:Neutrophils / Q000276:immunology*; D017063:Outcome Assessment, Health Care; D011446:Prospective Studies; D011859:Radiography; D012698:Serologic Tests; D014657:Vasculitis / Q000175:diagnosis / Q000276:immunology
D001323:Autoantibodies; D015415:Biomarkers