%0 Journal Article
%T Automatic Reading of ANCA-Slides: Evaluation of the AKLIDES System
%A Jan Damoiseaux
%A Kathleen Mallet
%A Mia Vaessen
%A Jos Austen
%A Jan Willem Cohen Tervaert
%J Journal of Immunology Research
%D 2012
%R 10.1155/2012/762874
%X The ANCA consensus prescribes screening by indirect immunofluorescence on neutrophils. We evaluated the first automated ANCA-pattern recognition system. C-ANCA and P-ANCA samples were selected from patients with ANCA-associated vasculitis (AAV). Non-AAV controls included sera from healthy controls , sera with possible interfering antibodies , or miscellaneous ANCA reactivity . ANCA slides were analysed by AKLIDES and routine fluorescence microscopy. The C-ANCA pattern was recognized by routine microscopy in 92% and 97% on ethanol- and formalin-fixed slides, respectively. AKLIDES reported C-ANCA in 74% and 95%, respectively. P-ANCA was recognized by routine microscopy on ethanol-fixed neutrophils in 90%, while AKLIDES reported P-ANCA in 80%. Typically, only 65% and 33% of these samples showed the expected C-ANCA on formalin-fixed neutrophils by routine microscopy and AKLIDES, respectively. A C- or P-ANCA pattern was observed on ethanol-fixed neutrophils in 28% and 23% of the controls by routine microscopy and AKLIDES, respectively. Only 5% of the controls revealed C-ANCA on formalin-fixed neutrophils by routine microscopy and AKLIDES. Altogether, automated ANCA-pattern recognition by AKLIDES is promising. Distinction of C- and P-ANCA is good, but sensitivity on ethanol-fixed neutrophils needs improvement. When optimized, pattern recognition software may play an important role in AAV diagnostics. 1. Introduction Detection of antineutrophil cytoplasmic antibodies (ANCAs) is relevant for the diagnosis of the ANCA-associated vasculitides (AAV), including granulomatosis with polyangiitis (GPA, previously referred to as WegenerĄ¯s granulomatosis), eosinophilic granulomatosis with polyangiitis (EGPA; previously referred to as the Churg-Straus syndrome), microscopic polyangiitis (MPA), and renal-limited necrotizing crescentic glomerulonephritis (NCGN) [1]. Classification criteria for these diseases have been defined by the American college of rheumatology (ACR) [2] and the Chapel Hill consensus conference [3]. The presence of ANCA, however, is not part of these criteria which are primarily based on clinical manifestations and histopathology as observed in biopsies obtained from the affected tissues. More recently, a novel consensus methodology for the classification of AAV was developed and validated for epidemiological studies [4]. Importantly, the latter classification criteria incorporated the ANCA status of the patient. The current international consensus on ANCA testing prescribes screening by indirect immunofluorescence (IIF) on ethanol-fixed neutrophils
%U http://www.hindawi.com/journals/jir/2012/762874/