ANCA are detectable in nearly all patients with active severe Wegener's granulomatosis.
BACKGROUND
The pathogenic significance of antineutrophilic cytoplasmic antibodies (ANCA) in Wegener's granulomatosis is controversial. Their presence is influenced by the extent, severity, and activity of the disease at the time of sampling. The objective of this study was to determine the frequency of ANCA in patients with active Wegener's granulomatosis and to assess the influence of disease severity on test results.


METHODS
Baseline serum samples from the 180 participants in a multicentric prospective trial were tested for ANCA by indirect immunofluorescence, direct enzyme-linked immunosorbent assay (ELISA), and capture ELISA. Disease activity was measured using the Birmingham Vasculitis Activity Score for Wegener's granulomatosis. All patients had active disease at enrollment. Patients were categorized as having severe (n=128) or limited (n=52) Wegener's granulomatosis.


RESULTS
When all ANCA detection methods were combined, 166 patients (92%) were ANCA positive, including 96% with severe disease and 83% with limited disease.


CONCLUSIONS
ANCA are detectable in nearly all patients with active severe Wegener's granulomatosis, but approximately 1 of 5 patients with active limited disease are ANCA negative. Immunofluorescence and both direct and capture ELISAs are required for optimal detection, suggesting that ANCA are not recognized equally well by all testing methods.
Finkielman
Javier D
JD
Thoracic Disease Research Unit, Division of Pulmonary and Critical Care Medicine, Mayo Clinic and Foundation, Rochester, Minn 55905, USA.
Lee
Augustine S
AS
Hummel
Amber M
AM
Viss
Margaret A
MA
Jacob
Gregory L
GL
Homburger
Henry A
HA
Peikert
Tobias
T
Hoffman
Gary S
GS
Merkel
Peter A
PA
Spiera
Robert
R
St Clair
E William
EW
Davis
John C
JC
McCune
W Joseph
WJ
Tibbs
Andrea K
AK
Ytterberg
Steven R
SR
Stone
John H
JH
Specks
Ulrich
U
D000328:Adult; D019268:Antibodies, Antineutrophil Cytoplasmic / Q000097:blood / Q000276:immunology*; D018450:Disease Progression; D005260:Female; D014890:Granulomatosis with Polyangiitis / Q000097:blood / Q000276:immunology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012720:Severity of Illness Index
D019268:Antibodies, Antineutrophil Cytoplasmic