Table 3. Performance of the Fungitell assay and the Wako β-glucan test using indicated cutoffs to distinguish between IFD and non-IFD patientsa.
| Parameter | Fungitell assay result (cutoff of ≥80 pg/mL) | Wako β-glucan test result (cutoff of ≥11 pg/mL) | Wako β-glucan test result (cutoff of ≥7 pg/mL) |
|---|---|---|---|
| Invasive candidiasis, n = 78 | |||
| True positives | 78 | 71 | 77 |
| False negatives | 0 | 7 | 1 |
| True negatives | 182 | 186 | 182 |
| False positives | 5 | 1 | 5 |
| Sensitivity, % (95% CIb) | 100.0 (95.3–100.0) | 91.0 (82.6–95.5) | 98.7 (93.0–99.9) |
| Specificity, % (95% CI) | 97.3 (93.8–98.8) | 99.5 (97.0–99.9) | 97.3 (93.8–98.8) |
| Invasive aspergillosis, n = 40 | |||
| True positives | 37 | 24 | 32 |
| False negatives | 3 | 16 | 8 |
| True negatives | 182 | 186 | 182 |
| False positives | 5 | 1 | 5 |
| Sensitivity, % (95% CI) | 92.5 (80.1–97.4) | 60.0 (44.6–73.6) | 80.0 (65.2–89.5) |
| Specificity, % (95% CI) | 97.3 (93.8–98.8) | 99.5 (97.0–99.9) | 97.3 (93.8–98.8) |
| Pneumocystis jirovecii pneumonia, n = 17 | |||
| True positives | 17 | 15 | 16 |
| False negatives | 0 | 2 | 1 |
| True negatives | 182 | 186 | 182 |
| False positives | 5 | 1 | 5 |
| Sensitivity, % (95% CI) | 100.0 (81.5–100) | 88.2 (65.6–97.9) | 94.1 (73.0–99.7) |
| Specificity, % (95% CI) | 97.3 (93.8–98.8) | 99.5 (97.0–99.9) | 97.3 (93.8–98.8) |
a Serum samples from 135 patients with invasive fungal disease (IFD) and from 187 patients without evidence of IFD (non-IFD controls) were tested with the Fungitell assay (FA) and the Wako β-glucan test (GT). The manufacturers’ cutoff values (FA, ≥80 pg/mL, and GT, ≥11 pg/mL) and, only for the GT, the optimized cutoff value (≥7 pg/mL) were used as sample’s positivity thresholds.
b CI, confidence interval.