Table 2.
Diagnostic performance of presence of gluten immunogenic peptides (GIPs) in stool and serum anti-tissue transglutaminase (tTG) IgA assays to detect mucosal damage in duodenal biopsies.
| Marsh0 | Marsh1/2/3 | Total | AUC | AG | SE | SP | PPV | NPV | |
|---|---|---|---|---|---|---|---|---|---|
| GIP (iVYCHECK, Biomedal) | |||||||||
| Positive (>0.15 µg/g) | 13 | 9 | 22 | - | 68.0% | 33.3% | 81.4% | 40.9% | 76.0% |
| Negative (<0.15 µg/g) | 57 | 18 | 75 | ||||||
| Anti-tTG IgA (Liaison, Diasorin) | |||||||||
| Positive (>8 UA/mL) | 0 | 2 | 2 | 0.549 | 75.4% | 11.8% | 100% | 100% | 74.6% |
| Negative (<8 UA/mL) | 44 | 15 | 59 | ||||||
| Anti-tTG IgA (Quanta Flash, Werfen) | |||||||||
| Positive (>20 UA/mL) | 6 | 3 | 9 | 0.564 | 59.4% | 30.0% | 72.7% | 33.3% | 69.6% |
| Negative (<20 UA/mL) | 16 | 7 | 23 | ||||||
AUC: area under the receiver operating characteristic curve; AG: agreement; SE: sensitivity; SP: specificity; PPV: positive predictive value; NPV: negative predictive value.