About this Journal Submit a Manuscript Table of Contents
Autoimmune Diseases
Volume 2011 (2011), Article ID 626495, 9 pages
http://dx.doi.org/10.4061/2011/626495
Clinical Study

Antineutrophil Cytoplasmic Antibodies Testing in a Large Cohort of Unselected Greek Patients

Department of Immunology-Histocompatibility, “Evangelismos” General Hospital, 10676 Athens, Greece

Received 18 October 2010; Revised 24 January 2011; Accepted 6 March 2011

Academic Editor: Alexander J. Szalai

Copyright © 2011 Konstantinos Tsiveriotis et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Objective. To retrospectively evaluate ANCA testing in a cohort of unselected Greek in- and outpatients. Methods. In 10803 consecutive serum samples, ANCA were tested by indirect immunofluorescence (IIF) and ELISA. ELISA in inpatients was performed only on IIF positive sera. Results. Low prevalence (6.0%) of IIF positive samples was observed. Among these samples, 63.5% presented perinuclear (p-ANCA), 9.3% cytoplasmic (c-ANCA) and 27.2% atypical (x-ANCA) pattern. 16.1% of p-ANCA were antimyeloperoxidase (anti-MPO) positive, whereas 68.3% of c-ANCA were antiproteinase-3 (anti-PR3) positive. Only 17 IIF negative outpatients' samples were ELISA positive. ANCA-associated vasculitides (AAV), connective tissue disorders and gastrointestinal disorders represented 20.5%, 23.9%, and 21.2% of positive results, respectively. AAV patients exhibited higher rates of MPO/PR3 specificity compared to non-AAV (93.8% versus 8%). Conclusions. This first paper on Greek patients supports that screening for ANCA by IIF and confirming positive results by ELISA minimize laboratory charges without sacrificing diagnostic accuracy.