Table 5.
Performance of the calprotectin assays for detecting disease activity in Crohn’s disease
| Assay | Cut off (µg/g) | SES-CD 1–4 (n=9) vs. SES-CD 0 (n=5) | SES-CD >4 (n=7, except Calprest/Calfast n=6) vs. SES-CD 0 (n=5) | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Sensitivity | Specificity | NPV | PPV | LR+ | LR– | Sensitivity | Specificity | NPV | PPV | LR+ | LR– | ||
| Calprolab | 89 | 22 | 80 | 36 | 67 | 1.1 | 1.0 | 86 | 80 | 80 | 86 | 4.3 | 0.18 |
| QB BM | 77.5 | 44 | 80 | 44 | 80 | 2.2 | 0.7 | 100 | 80 | 100 | 88 | 5 | 0 |
| Phadia EliA | 28.5 | 22 | 80 | 36 | 67 | 1.1 | 1.0 | 86 | 80 | 80 | 86 | 4.2 | 0.21 |
| Calfast | 75.5 | 33 | 80 | 40 | 75 | 1.7 | 0.8 | 83 | 80 | 80 | 83 | 3.3 | 0.2 |
| Calprest | 46.5 | 44 | 80 | 44 | 80 | 2.2 | 0.7 | 100 | 80 | 100 | 86 | 5 | 0 |
| Certest | 50 | 33 | 40 | 25 | 50 | 0.56 | 1.7 | 100 | 40 | 100 | 70 | 1.7 | 0 |
| 200 | 22 | 100 | 42 | 100 | / | 0.8 | 71 | 100 | 71 | 100 | / | 0.3 | |
IBD, inflammatory bowel disease; LR+, positive likelihood ratio; LR–, negative likelihood ratio; NPV, negative predictive value; PPV, positive predictive value; QB BM, Quantum Blue Bühlmann; SES-CD, simple endoscopic score for Crohn’s disease.