Page 182 - The Vasculitides, Volume 1: General Considerations and Systemic Vasculitis

158 Elena Csernok

Moreover, ANCA-negative patients and generalized GPA tend to be younger in age,
more likely to be of female gender, with less lung and kidney involvement, lower rate of
relapse, and improved outcome compared to those ANCA-positive patients.

Conclusion

ANCA serology and the associated clinical manifestation of AAV continue to attract the
attention of clinicians and investigators alike. In addition to be providing a useful diagnostic
tool for small vessel vasculitis, ANCA testing may be useful in predicting relapses and in
guiding therapy. Worldwide, most laboratories perform IFT to screen for ANCA positivity
patients with small-vessel vasculitis, with later confirmation employing PR3- and MPO-
ANCA immunometric assays. Promising new forms of ANCA detection in AAV that may
one day replace present methodologies of combined analysis employing IFT and ELISA
should be analyzed prospectively in multicenter studies.

Notwithstanding, any testing strategy applicable to vasculitis should be able to identify
relevant ANCA target antigens since these correlate best with the clinicopathological aspects,
disease activity, and propensity for relapse. The solution to problems regarding ANCA-
diagnosis lies in focusing upon the implementation of IFT and ELISA testing according to
international consensus, with cautious use of commercial assays, and restriction of such tests
to those with the highest pretest probability of AAV.

References

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[3] Csernok, E., Lamprecht, P., W. L. Gross. Diagnostic significance of ANCA in
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[4] Savige, J., Gillis, D., Benson, E., Davies, D., et al. International consensus statement on
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[5] Csernok, E., Holle, J. U. Twenty-years with ANCA: how to test for ANCA–evidence
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[6] Csernok, E., Holle, J., Hellmich, B., et al. Evaluation of capture ELISA for detection of
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[7] Holle, J. U., Hellmich, B., Backes, M., et al. Variations in performance characteristics
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