TABLE 2.
PPA and NPA of QIAstat-Dx ME Panel performance by target based on concordance with results from BioFire FilmArray ME Panel a
| Pathogen type | Pathogen | PPA | NPA | ||
|---|---|---|---|---|---|
| TP/(TP + FN) | % (95% CI) | TN/(TN + FP) | % (95% CI) | ||
| All | All pathogens | 135/146 | 92.5 (87.0–95.7) | 7,377/7,387 | 99.9 (99.8–99.9) |
| Bacteria | Escherichia coli K1 | 1/1 | 100.0 (20.7–100.0) | 579/579 | 100.0 (99.3–100.0) |
| Haemophilus influenzae | 4/5 | 80.0 (37.6–96.4) | 572/574 | 99.7 (98.7–99.9) | |
| Listeria monocytogenes | 1/1 | 100.0 (20.7–100.0) | 578/578 | 100.0 (99.3–100.0) | |
| Neisseria meningitidis (encapsulated) | 1/1 | 100.0 (20.7–100.0) | 578/578 | 100.0 (99.3–100.0) | |
| Streptococcus agalactiae | 3/3 | 100.0 (43.9–100.0) | 576/576 | 100.0 (99.3–100.0) | |
| Streptococcus pneumoniae | 15/17 | 88.2 (65.7–96.7) | 561/562 | 99.8 (99.0–100.0) | |
| Overall (bacteria) | 25/28 | 89.3 (72.8–96.3) | 3,444/3,447 | 99.9 (99.7–100.0) | |
| Virus | Enterovirus | 7/9 | 77.8 (45.3–93.7) | 569/570 | 99.8 (99.0–100.0) |
| Herpes simplex virus 1 | 20/20 | 100.0 (83.9–100.0) | 561/561 | 100.0 (99,3–100.0) | |
| Herpes simplex virus 2 | 21/23 | 91.3 (73.2–97.6) | 555/557 | 99.6 (98.7–99.9) | |
| Human parechovirus | 579/579 | 100.0 (99.3–100.0) | |||
| Human herpes virus 6 | 9/10 | 90.0 (59.6–98.2) | 568/570 | 99.7 (98.7–99.9) | |
| Varicella zoster virus | 52/55 | 94.6 (85.2–98.1) | 523/525 | 99.6 (98.6–99.9) | |
| Overall (virus) | 109/117 | 93.2 (87.1–96.5) | 3,355/3,362 | 99.8 (99.6–99.9) | |
| Yeast | Cryptococcus neoformans/gattii (not differentiated) | 1/1 | 100.0 (20.7–100.0) | 578/578 | 100.0 (99.3–100.0) |
PPA analysis includes only targets with reference results detected in clinical samples tested, thus Mycoplasma pneumoniae, Streptococcus pyogenes, and human parechovirus are excluded. Specificity analysis includes targets with reference results not detected in clinical samples. Mycoplasma pneumoniae and Streptococcus pyogenes are excluded because they were not detected in the clinical samples tested and they are not tested by the BioFire FilmArray ME Panel. In this study, the internal control failed to amplify for six clinical specimens. However, these specimens tested positive for the following pathogens: Escherichia coli K1 (one case), herpes simplex virus 1 (two cases), herpes simplex virus 2 (one case), varicella zoster virus (one case), and human herpes virus 6 (one case). These positive results were considered valid, while the rest of the results for that run were considered invalid.