Table 4.
Comparison of ELISA detection of autoantibodies recognizing citrullinated minus noncitrullinated recombinant rat filaggrin, expressed as differential ACRF (dACRF) to indirect immunofluorescence assays for AKA and APF detection and ELISA detection of anti-CCP antibodies in sera from 314 patients with very early arthritis (group 2)
| dACRF | |||
|---|---|---|---|
| Autoantibody | positive(n = 58) | negative (n = 256) | Kappa-value |
| AKA | 0·66 | ||
| positive (n = 45) | 37 (63·8) | 8 (3·1) | |
| negative (n = 269) | 21 (36·2) | 248 (96·9) | |
| APF | 0·63 | ||
| positive (n = 77) | 48 (82·7) | 89 (11·3) | |
| negative (n = 237) | 10 (17·3) | 227 (88·7) | |
| anti-CCP | 0·75 | ||
| positive (n = 74) | 53 (91·4) | 21 (8·2) | |
| negative (n = 240) | 5 (8·6) | 235 (91·8) | |
Results are expressed in numbers of patients (% of dACRF-positive or -negative patients). AKA, anti-keratin antibodies; APF, anti-perinuclear factor; dACRF, autoAb recognizing citrullinated minus noncitrullinated rat filaggrin; anti-CCP, anti-cyclic-citrullinated peptides.