TABLE 6.
BCID-GN panel antimicrobial resistance markers clinical performance
| Target | Clinical samples |
Contrived samples |
Combined samples |
|||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| PPA |
NPA |
PPA |
NPA |
PPA |
NPA |
|||||||
| TP/TP+FN | % (95% CI) | TN/TN+FP | % (95% CI) | TP/TP+FN | % (95% CI) | TN/TN+FP | % (95% CI) | TP/TP+FN | % (95% CI) | TN/TN+FP | % (95% CI) | |
| CTX-Ma | 74/85 | 87.1 (78.3–92.6) | 754/754 | 100 (99.5–100) | 75/75 | 100 (95.1–100) | 437/437 | 100 (99.1–100) | 149/160 | 93.1 (88.1–96.1) | 1,191/1,191 | 100 (99.7–100) |
| IMP | 0/0 | 829/829 | 100 (99.5–100) | 40/40 | 100 (91.2–100) | 436/436 | 100 (99.1–100) | 40/40 | 100 (91.2–100) | 1,265/1,265 | 100 (99.7–100) | |
| KPC | 7/8 | 87.5 (52.9–97.8) | 821/822 | 99.9 (99.3–100) | 44/44 | 100 (92.0–100) | 477/477 | 100 (99.2–100) | 51/52 | 98.1 (89.9–99.7) | 1,298/1,299 | 99.9 (99.6–100) |
| NDM | 0/0 | 829/829 | 100 (99.5–100) | 54/54 | 100 (93.4–100) | 422/422 | 100 (99.1–100) | 54/54 | 100 (93.4–100) | 1,251/1,251 | 100 (99.7–100) | |
| OXAb | 10/13 | 76.9 (49.7–91.8) | 814/816 | 99.8 (99.1–99.9) | 37/37 | 100 (90.6–100) | 439/439 | 100 (99.1–100) | 47/50 | 94.0 (83.8–97.9) | 1,253/1,255 | 99.8 (99.4–100) |
| VIM | 0/0 | 829/829 | 100 (99.5–100) | 42/42 | 100 (91.6–100) | 434/434 | 100 (99.1–100) | 42/42 | 100 (91.6–100) | 1,263/1,263 | 100 (99.7–100) | |
a
For 8/11 remaining false-negative CTX-M target detections, discordant analysis was not evaluable due to sample contamination.
b
In 1/3 false-negative clinical samples, the OXA signal was above the threshold for detection; however, an associated organism was not detected by the BCID-GN, and the OXA target was reported as NA. One additional false-negative sample was tested with an FDA-cleared multiplex assay, and OXA was not detected. The isolate from the remaining false-negative sample tested negative for OXA-23 and OXA-48 by qPCR.