Table 3

Comparison of visual and automated interpretation of IIF ANCA patterns of the 'test set' patients (n = 342) on ethN and formN.

ethN

Automated interpretation by AKLIDES™

n (%)

cytoplasmic

nuclear

atypical

negative

cytoplasmic

59 (17.2)

0 (0)

7 (2.0)

22 (6.4)

nuclear

0 (0)

61 (17.8)

4 (1.2)

0 (0)

atypical

3 (0.9)

10 (2.9)

40 (11.7)

2 (0.6)

negative

0 (0)

0 (0)

1 (0.3)

133 (38.9)

Visual interpretation

formN

n (%)

cytoplasmic

atypical

negative

cytoplasmic

91 (26.6)

0 (0)

9 (2.6)

atypical

8 (2.3)

0 (0)

0 (0)

negative

9 (2.6)

0 (0)

225 (65.8)

ANCA IIF patterns were first read automatically with AKLIDES™ followed by manual interpretation with a routine fluorescence microscope. Both interpretation methods demonstrated good agreement on ethN and formN (κ = 0.746, 95% CI: 0.667 to 0.825; κ = 0.847, 95% CI: 0.79 to 0,904; respectively). ANCA, antineutrophil cytoplasmic antibody; ethN, ethanol-fixed neutrophils; formN, formalin-fixed neutrophils; IIF, indirect immunofluorescence.

Knütter et al. Arthritis Research & Therapy 2012 14:R271   doi:10.1186/ar4119