Automatic reading of ANCA-slides: evaluation of the AKLIDES system

Clin Dev Immunol. 2012:2012:762874. doi: 10.1155/2012/762874. Epub 2012 Nov 5.

Abstract

The ANCA consensus prescribes screening by indirect immunofluorescence on neutrophils. We evaluated the first automated ANCA-pattern recognition system. C-ANCA (n = 39) and P-ANCA (n = 40) samples were selected from patients with ANCA-associated vasculitis (AAV). Non-AAV controls included sera from healthy controls (n = 40), sera with possible interfering antibodies (n = 46), or miscellaneous ANCA reactivity (n = 31). 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.

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Anti-Neutrophil Cytoplasmic Antibody-Associated Vasculitis / blood*
  • Anti-Neutrophil Cytoplasmic Antibody-Associated Vasculitis / diagnosis*
  • Anti-Neutrophil Cytoplasmic Antibody-Associated Vasculitis / immunology
  • Anti-Neutrophil Cytoplasmic Antibody-Associated Vasculitis / pathology
  • Antibodies, Antineutrophil Cytoplasmic / blood*
  • Antibodies, Antineutrophil Cytoplasmic / immunology
  • Female
  • Fluorescent Antibody Technique, Indirect / methods*
  • Humans
  • Male
  • Microscopy, Fluorescence / methods
  • Middle Aged
  • Neutrophils / immunology
  • Neutrophils / pathology
  • Pattern Recognition, Automated / methods*
  • Young Adult

Substances

  • Antibodies, Antineutrophil Cytoplasmic