Diagnostic performance of commercially available enzyme linked immunosorbent assay kits for detection of MPO-ANCA compared with direct immunofluorescence using optimum cut off levels calculated by ROC curve analysis
| Test | Optimum cut off | Sensitivity | Specificity | PPV | NPV | AUC | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Mean | 95% CI | Mean | 95% CI | Mean | 95% CI | |||||||||||||
| AUC, area under the curve; CI, confidence interval; IFT, indirect immunofluorescence technique; IHELI, in-house enzyme linked immunosorbent assay; MPO-ANCA, antineutrophil cytoplasmic antibodies to myeloperoxidase; NPV, negative predictive value; PA, P-ANCA; PPV, positive predictive value; ROC, receiver operating characteristic. | ||||||||||||||||||
| IFT (PA) | >0 | 86.7 | 59.9 to 98.0 | 98 | 91.7 to 99.7 | 86.67 | 96.15 | 0.931 | 0.852 to 0.976 | |||||||||
| IHELI | >0 | 60.0 | 32.2 to 83.6 | 100 | 94.4 to 100.0 | 100 | 89.29 | 0.800 | 0.696 to 0.881 | |||||||||
| A | >1.85 | 66.7 | 38.4 to 88.1 | 94 | 87.1 to 99.0 | 92.31 | 94.34 | 0.866 | 0.772 to 0.932 | |||||||||
| B | >12.06 | 80.0 | 51.9 to 95.4 | 92 | 85.0 to 98.3 | 83.34 | 94.34 | 0.885 | 0.794 to 0.945 | |||||||||
| E | >3 | 73.7 | 44.9 to 92.0 | 90 | 81.0 to 96.5 | 57.89 | 91.31 | 0.905 | 0.819 to 0.959 | |||||||||
| F | >2.03 | 86.7 | 59.5 to 98.0 | 94 | 87.1 to 99.0 | 100 | 94.34 | 0.933 | 0.854 to 0.976 | |||||||||
| G | >1.57 | 80.0 | 51.9 to 95.4 | 90 | 81.0 to 96.5 | 70.58 | 95.74 | 0.933 | 0.855 to 0.977 | |||||||||
| H | >0.77 | 80.0 | 51.9 to 95.4 | 98 | 94.4 to 100 | 86.67 | 100 | 0.907 | 0.821 to 0.960 | |||||||||
| I | >4.33 | 80.0 | 51.9 to 95.4 | 98 | 91.7 to 99.7 | 85.71 | 98.04 | 0.883 | 0.792 to 0.944 | |||||||||
| J | >2.56 | 66.7 | 38.4 to 88.1 | 96 | 89.3 to 99.5 | 77.78 | 100 | 0.846 | 0.748 to 0.917 | |||||||||
| K | >5.34 | 93.3 | 68.0 to 98.9 | 92 | 81.0 to 96.5 | 56.00 | 100 | 0.956 | 0.886 to 0.989 | |||||||||
| L | >0 | 73.3 | 44.9 to 92.0 | 100 | 94.4 to 100 | 92.31 | 96.15 | 0.867 | 0.772 to 0.932 | |||||||||
| M | >4.43 | 80.0 | 51.9 to 95.4 | 98 | 94.4 to 100 | 100 | 94.34 | 0.878 | 0.786 to 0.940 | |||||||||