Introduction
Materials and methods
Assessment of the Carba NP and CarbAcineto tests: strain collection and cultivation media
Species, total number | Carbapenemase genes | No. |
---|---|---|
Carbapenemase-positive, n = 81 | ||
Enterobacteriaceae, n = 34 | ||
K. pneumoniae, n = 15 | KPC | 4 |
NDM | 5 | |
VIM | 2 | |
IMP | 1 | |
OXA-48 | 3 | |
K. oxytoca, n = 3 | NDM | 1 |
VIM | 2 | |
E. coli, n = 9 | KPC | 2 |
NDM | 4 | |
OXA-48 | 3 | |
E. cloacae, n = 5 | KPC | 1 |
NDM | 1 | |
VIM | 3 | |
C. freundii, n = 2 | KPC | 2 |
Pseudomonas spp., n = 15 | ||
P. aeruginosa, n = 9 | VIM | 8 |
IMP | 1 | |
P. putida, n = 6 | VIM | 6 |
Acinetobacter spp., n = 32 | ||
A. baumannii
| VIM | 6 |
A. lwoffii
| VIM | 7 |
A. junii
| VIM | 3 |
A. baumannii
| OXA-23 | 9 |
A. baumannii
| OXA-24/40 | 6 |
A. baumannii
| OXA-58 | 1 |
Carbapenemase-negative, n = 26a
| ||
K. pneumoniae
| No | 10 |
P. aeruginosa
| No | 6 |
Acinetobacter spp.
| No | 10 |
Microbiological media | Manufacturer | VIM; n = 7a
| IMP; n = 1a
| NDM; n = 11a
| KPC; n = 9a
| OXA-48; n = 6a
| c-npb; n = 10a
| ||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
+ | +/− | − | NG (NI) | + | NG | + | +/− | − | NG (NI) | + | NG | + | +/− | − | NG | + | +/− | − | NG (NI) | ||
Columbia blood agar | BD | 7 | 1 | 10 | (1) | 9 | 6 | 10 | |||||||||||||
chromID CPS agar | bioMérieux | 7 | 1 | 11 | 9 | 6 | 10 | ||||||||||||||
CHROMagar Orientation Medium | BD | 7 | 1 | 11 | 9 | 6 | 1 | 9 | |||||||||||||
Brilliance UTI agar | Oxoid | 7 | 1 | 11 | 9 | 5 | 1 | 3 | 7 | ||||||||||||
Brilliance UTI Clarity agar | Oxoid | 7 | 1 | 11 | 9 | 5 | 1 | 3 | 7 | ||||||||||||
Brilliance ESBL agar | Oxoid | 6 | (1) | 1 | 10 | (1) | 9 | 3 | 1 | 2 | 1 | 9 | |||||||||
chromID ESBL agar | bioMérieux | 7 | 1 | 11 | 9 | 5 | 1 | 9 | 1 | ||||||||||||
Brilliance CRE agar | Oxoid | 6 | 1 | 1 | 11 | 8 | 1 | 2 | 1 | 3 | 2 | 8 | |||||||||
chromID CARBA agar | bioMérieux | 3 | 2 | 2 | 1 | 10 | 1 | 9 | 5 | 1 | 7 | 3 | |||||||||
KPC CHROM agar | GRASO | 7 | 1 | 11 | 9 | 5 | 1 | 2 | 1 | 6 | 1 | ||||||||||
chromID OXA-48 agar | bioMérieux | 7 | 1 | 1 | 10 | 9 | 6 | 10 | |||||||||||||
MH | BD | 7 | 1 | 10 | 1 | 9 | 6 | 2 | 7 | (1) | |||||||||||
MHE | bioMérieux | 7 | 1 | 10 | 1 | 9 | 6 | 8 | (2) | ||||||||||||
MHF | bioMérieux | 1 | 6 | 1 | 2 | 3 | 6 | 9 | 6 | 10 | |||||||||||
MH | Oxoid | 7 | 1 | 11 | 9 | 5 | 1 | 3 | (7) | ||||||||||||
MH | GRASO | 7 | 1 | 11 | 9 | 6 | 1 | 6 | (3) | ||||||||||||
MH | Liofilchem | 7 | 1 | 10 | 1 | 9 | 6 | 9 | (1) | ||||||||||||
MH | Bio-Rad | 5 | 2 | 1 | 2 | 3 | 6 | 9 | 6 | 1 | 1 | 8 |
Carba NP | CarbAcineto | ||||||||||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Pseudomonas spp. |
Acinetobacter spp. | ||||||||||||||||||||||
Microbiological media | Manufacturer | VIM; n = 14a
| IMP; n = 1a
| c-npb; n = 6a
| VIM; n = 16a
| OXA-like; n = 16a
| c-npb; n = 10a
| ||||||||||||||||
+ | +/− | − | NG (NI) | + | NG (NI) | + | +/− | − | NG (NI) | + | +/− | − | NG (NI) | + | +/− | − | NG (NI) | + | +/− | − | NG (NI) | ||
Columbia blood agar | BD | 14 | 1 | 6 | 16 | 16 | 10 | ||||||||||||||||
chromID CPS agar | bioMérieux | 14 | 1 | 6 | 14 | 2 | 16 | 9 | (1) | ||||||||||||||
CHROMagar Orientation Medium | BD | 13 | 1 | 1 | 2 | 4 | 11 | 4 | 1 | 15 | 1 | 1 | 9 | ||||||||||
Brilliance UTI agar | Oxoid | 14 | 1 | 3 | 3 | 12 | 4 | 15 | 1 | 9 | (1) | ||||||||||||
Brilliance UTI Clarity agar | Oxoid | 12 | 1 | (1) | 1 | 1 | 2 | 3 | 14 | 2 | 15 | 1 | 1 | 8 | (1) | ||||||||
Brilliance ESBL agar | Oxoid | 8 | 3 | 2 | (1) | 1 | 1 | 5 | 13 (3) | 13 | 2 | 1 | 1 | 2 | 6 (1) | ||||||||
chromID ESBL agar | bioMérieux | 12 | 1 | 1 | 1 | 1 | 4 | 1 | 14 | 1 | 1 | 15 | 1 | 8 | 1 (1) | ||||||||
Brilliance CRE agar | Oxoid | 14 | 1 | 1 | 3 | 2 | 10 | 2 | 4 | 15 | 1 | 7 | 2 (1) | ||||||||||
chromID CARBA agar | bioMérieux | 10 | 1 | 3 | 1 | 1 | 1 | 3 | 1 | 10 | 6 | 15 | 1 | 8 | 2 | ||||||||
KPC CHROM agar | GRASO | 12 | 2 | 1 | 6 | 11 | 2 | 3 | 15 | 1 | 8 | 2 | |||||||||||
chromID OXA-48 agar | bioMérieux | 3 | 3 | 8 | 1 | 3 | 3 | 1 | 9 | 6 | 9 | 2 | 4 | 1 | 3 | 7 | |||||||
MH | Bio-Rad | 9 | 5 | 1 | 1 | 5 | 16 | 16 | 1 | 1 | 8 | ||||||||||||
MH | Liofilchem | 13 | 1 | 1 | 1 | 5 | 16 | 14 | 1 | 1 | 10 | ||||||||||||
MH | GRASO | 13 | 1 | 1 | 6 | 16 | 16 | 1 | 8 | (1) | |||||||||||||
MH | BD | 14 | 1 | 6 | 16 | 15 | 1 | 1 | 2 | 7 | |||||||||||||
MH | Oxoid | 13 | 1 | 1 | 6 | 16 | 16 | 10 | |||||||||||||||
MHE | bioMérieux | 14 | 1 | 2 | 4 | 16 | 16 | 9 | (1) | ||||||||||||||
MHF | bioMérieux | 5 | 3 | 6 | 1 | 6 | 11 | 3 | 2 | 15 | 1 | 1 | 8 | (1) |
The Carba NP and CarbAcineto tests in routine reference diagnostics
Enterobacteriaceae (total, n = 915)a
|
Pseudomonas spp. (total, n = 309)a
|
Acinetobacter spp. (total, n = 58)a
|
---|---|---|
Carbapenemase-positive, n = 451 | Carbapenemase-positive, n = 118 | Carbapenemase-positive, n = 54 |
Carba NP positive, n = 432 | Carba NP positive, n = 115 | CarbAcineto positive, n = 48 |
KPC, n = 77 | VIM, n = 115 |
A. baumannii VIM, n = 2 |
K. pneumoniae, n = 75 |
P. aeruginosa, n = 111 |
A. lwoffii VIM, n = 3 |
E. coli, n = 1 |
P. putida, n = 4 |
A. junii VIM, n = 3 |
E. cloacae, n = 1 |
A. baumannii OXA-24/40-like, n = 30 | |
NDM, n = 275 |
A. baumannii OXA-23-like, n = 10 | |
K. pneumoniae, n = 267 | ||
E. coli, n = 2 | ||
E. cloacae, n = 4 | ||
S. marcescens, n = 2 | ||
VIM, n = 57 | ||
K. pneumoniae, n = 12 | ||
E. coli, n = 6 | ||
E. cloacae, n = 26 | ||
C. freundii, n = 8 | ||
S. marcescens, n = 4 | ||
K. oxytoca, n = 1 | ||
OXA-48, n = 23 | ||
K. pneumoniae, n = 7 | ||
E. coli, n = 14 | ||
E. aerogenes, n = 2 | ||
Carba NP questionable, n = 18 | Carba NP questionable, n = 3 | CarbAcineto questionable, n = 6 |
K. pneumoniae NDM, n = 14 |
P. aeruginosa VIM, n = 3 |
A. baumannii OXA-24/40-like, n = 1 |
K. pneumoniae OXA-48, n = 1 |
A. baumannii OXA-23-like, n = 3 | |
E. coli OXA-48, n = 1 |
A. baumannii OXA-58, n = 2 | |
E. cloacae KPC, n = 1 | ||
C. freundii VIM, n = 1 | ||
Carba NP not interpretable, n = 1 | ||
K. pneumoniae NDM, n = 1 | ||
Carbapenemase-negative, n = 464 | Carbapenemase-negative, n = 191 | Carbapenemase-negative, n = 4 |
Carba NP negative, n = 433 | Carba NP negative, n = 189 | CarbAcineto negative, n = 4 |
Carba NP questionable, n = 30 | Carba NP questionable, n = 2 | |
K. pneumoniae, n = 19 |
P. aeruginosa, n = 2 | |
E. cloacae, n = 9 | ||
S. marcescens, n = 1 | ||
P. mirabilis, n = 1 | ||
Carba NP not interpretable, n = 1 | ||
K. pneumoniae, n = 1 | ||
Sensitivity 95.8% (95% CI, 93.9–97.6%) | Sensitivity 97.5% (95% CI, 94.6–100%) | Sensitivity 88.9% (95% CI, 80.4–97.4%) |
Specificity 93.3% (95% CI, 90.9–95.6%) | Specificity 99.0% (95% CI, 97.6–100%) | |
PPV 95.8% (95% CI, 93.9–97.6%) | PPV 97.5% (95% CI, 94.6–100%) | PPV 88.9% (95% CI, 80.4–97.4%) |
NPV 93.3% (95% CI, 90.9–95.6%) | NPV 99.0% (95% CI, 97.6–100%) |