Table 1.
Performance of the Accelerate Pheno™ system and VITEK® 2 systems compared with BMD for Gram-negative bacterial species (n = 62)
| BMD |
Accelerate Pheno™ system [% (n/N)] |
VITEK® 2 system [% (n/N)] |
||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Antimicrobial | n | S | I | R | categorical agreementa | errors |
categorical agreementa | errors |
||||
| VMEs | MEs | mEs | VMEs | MEs | mEs | |||||||
| E. coli | 19 | |||||||||||
| TZP | 16 | 1 | 2 | 94.7 (18/19) | 0.0 (0/2) | 0.0 (0/16) | 5.3 (1/19) | 89.5 (17/19) | 0.0 (0/2) | 0.0 (0/16) | 10.5 (2/19) | |
| cefepime | 13 | 1 | 5 | 78.9 (15/19) | 0.0 (0/5) | 0.0 (0/13) | 21.1 (4/19) | 84.2 (16/19) | 0.0 (0/5) | 0.0 (0/13) | 15.8 (3/19) | |
| ceftazidime | 11 | 3 | 5 | 89.5 (17/19) | 0.0 (0/5) | 0.0 (0/11) | 10.5 (2/19) | 84.2 (16/19) | 0.0 (0/5) | 0.0 (0/11) | 15.8 (3/19) | |
| ertapenem | 19 | 0 | 0 | 100 (19/19) | NA (0/0) | 0.0 (0/19) | 0.0 (0/19) | 100 (19/19) | NA (0/0) | 0.0 (0/19) | 0.0 (0/19) | |
| meropenem | 19 | 0 | 0 | 100 (19/19) | NA (0/0) | 0.0 (0/19) | 0.0 (0/19) | 94.7 (18/19) | NA (0/0) | 0.0 (0/19) | 5.3 (1/19) | |
| amikacin | 18 | 1 | 0 | 94.7 (18/19) | NA (0/0) | 0.0 (0/18) | 5.3 (1/19) | 78.9 (15/19) | NA (0/0) | 0.0 (0/18) | 21.1 (4/19) | |
| gentamicin | 16 | 0 | 3 | 100 (19/19) | 0.0 (0/3) | 0.0 (0/16) | 0.0 (0/19) | 94.7 (18/19) | 0.0 (0/3) | 0.0 (0/16) | 5.3 (1/19) | |
| ciprofloxacin | 10 | 1 | 8 | 94.7 (18/19) | 0.0 (0/8) | 0.0 (0/10) | 5.3 (1/19) | 94.7 (18/19) | 0.0 (0/8) | 0.0 (0/10) | 5.3 (1/19) | |
| colistin | 19 | 0 | 0 | 94.7 (18/19) | NA (0/0) | 5.3 (1/19) | 0.0 (0/19) | 100 (19/19) | NA (0/0) | 0.0 (0/19) | 0.0 (0/19) | |
| K. pneumoniae | 18 | |||||||||||
| TZP | 6 | 2 | 10 | 83.3 (15/18) | 10.0 (1/10) | 0.0 (0/6) | 11.1 (2/18) | 83.3 (15/18) | 0.0 (0/10) | 0.0 (0/6) | 16.7 (3/18) | |
| cefepime | 8 | 0 | 10 | 100 (17/17) | 0.0 (0/9) | 0.0 (0/8) | 0.0 (0/17) | 88.9 (16/18) | 0.0 (0/10) | 0.0 (0/8) | 11.1 (2/18) | |
| ceftazidime | 8 | 0 | 10 | 100 (18/18) | 0.0 (0/10) | 0.0 (0/8) | 0.0 (0/18) | 100 (18/18) | 0.0 (0/10) | 0.0 (0/8) | 0.0 (0/18) | |
| ertapenem | 9 | 0 | 9 | 94.4 (17/18) | 11.1 (1/9) | 0.0 (0/9) | 0.0 (0/18) | 100 (18/18) | 0.0 (0/9) | 0.0 (0/9) | 0.0 (0/18) | |
| meropenem | 9 | 0 | 9 | 88.9 (16/18) | 22.2 (2/9) | 0.0 (0/9) | 0.0 (0/18) | 100 (18/18) | 0.0 (0/9) | 0.0 (0/9) | 0.0 (0/18) | |
| amikacin | 15 | 3 | 0 | 77.8 (14/18) | NA (0/0) | 0.0 (0/15) | 22.2 (4/18) | 72.2 (13/18) | NA (0/0) | 13.3 (2/15) | 16.7 (3/18) | |
| gentamicin | 14 | 0 | 4 | 94.4 (17/18) | 0.0 (0/4) | 0.0 (0/14) | 5.6 (1/18) | 72.2 (13/18) | 0.0 (0/4) | 0.0 (0/14) | 27.8 (5/18) | |
| ciprofloxacin | 8 | 0 | 10 | 94.4 (17/18) | 10.0 (1/10) | 0.0 (0/8) | 0.0 (0/18) | 100 (18/18) | 0.0 (0/10) | 0.0 (0/8) | 0.0 (0/18) | |
| colistin | 16 | 0 | 2 | 94.4 (17/18) | 0.0 (0/2) | 6.3 (1/16) | 0.0 (0/18) | 94.4 (17/18) | 50.0 (1/2) | 0.0 (0/16) | 0.0 (0/18) | |
| P. aeruginosa | 8 | |||||||||||
| TZP | 3 | 0 | 5 | 100 (8/8) | 0.0 (0/5) | 0.0 (0/3) | 0.0 (0/8) | 87.5 (7/8) | 0.0 (0/5) | 33.3 (1/3) | 0.0 (0/8) | |
| cefepime | 4 | 0 | 4 | 100 (8/8) | 0.0 (0/4) | 0.0 (0/4) | 0.0 (0/8) | 100 (8/8) | 0.0 (0/4) | 0.0 (0/4) | 0.0 (0/8) | |
| ceftazidime | 3 | 0 | 5 | 62.5 (5/8) | 0.0 (0/5) | 100 (3/3) | 0.0 (0/8) | 87.5 (7/8) | 0.0 (0/5) | 33.3 (1/3) | 0.0 (0/8) | |
| meropenem | 3 | 0 | 5 | 87.5 (7/8) | 0.0 (0/5) | 0.0 (0/3) | 12.5 (1/8) | 87.5 (7/8) | 0.0 (0/5) | 0.0 (0/3) | 12.5 (1/8) | |
| amikacin | 3 | 1 | 4 | 87.5 (7/8) | 0.0 (0/4) | 0.0 (0/3) | 12.5 (1/8) | 100 (8/8) | 0.0 (0/4) | 0.0 (0/3) | 0.0 (0/8) | |
| gentamicin | 2 | 0 | 6 | 100 (8/8) | 0.0 (0/6) | 0.0 (0/2) | 0.0 (0/8) | 87.5 (7/8) | 16.6 (1/6) | 0.0 (0/2) | 0.0 (0/8) | |
| ciprofloxacin | 1 | 0 | 7 | 87.5 (7/8) | 14.3 (1/7) | 0.0 (0/1) | 0.0 (0/8) | 100 (8/8) | 0.0 (0/7) | 0.0 (0/1) | 0.0 (0/8) | |
| colistin | 8 | 0 | 0 | 100 (8/8) | NA (0/0) | 0.0 (0/8) | 0.0 (0/8) | 100 (8/8) | NA (0/0) | 0.0 (0/8) | 0.0 (0/8) | |
| A. baumannii | 8 | |||||||||||
| meropenem | 1 | 0 | 7 | 100 (8/8) | 0.0 (0/7) | 0.0 (0/1) | 0.0 (0/8) | 100 (8/8) | 0.0 (0/7) | 0.0 (0/1) | 0.0 (0/8) | |
| amikacin | 2 | 1 | 5 | 87.5 (7/8) | 0.0 (0/5) | 0.0 (0/2) | 12.5 (1/8) | 87.5 (7/8) | 0.0 (0/5) | 0.0 (0/2) | 12.5 (1/8) | |
| ciprofloxacin | 1 | 0 | 7 | 100 (8/8) | 0.0 (0/7) | 0.0 (0/1) | 0.0 (0/8) | 100 (8/8) | 0.0 (0/7) | 0.0 (0/1) | 0.0 (0/8) | |
| colistin | 6 | 0 | 2 | 62.5 (5/8) | 0.0 (0/2) | 50.0 (3/6) | 0.0 (0/8) | 87.5 (7/8) | 50.0 (1/2) | 0.0 (0/6) | 0.0 (0/8) | |
| Enterobacter spp. | 4 | |||||||||||
| TZP | 3 | 0 | 1 | 75.0 (3/4) | 0.0 (0/1) | 33.3 (1/3) | 0.0 (0/4) | 75.0 (3/4) | 0.0 (0/1) | 0.0 (0/3) | 25.0 (1/4) | |
| cefepime | 4 | 0 | 0 | 100 (4/4) | NA (0/0) | 0.0 (0/4) | 0.0 (0/4) | 100 (4/4) | NA (0/0) | 0.0 (0/4) | 0.0 (0/4) | |
| ceftazidime | 2 | 1 | 1 | 75.0 (3/4) | 0.0 (0/1) | 0.0 (0/2) | 25.0 (1/4) | 75.0 (3/4) | 0.0 (0/1) | 0.0 (0/2) | 25.0 (1/4) | |
| ertapenem | 3 | 1 | 0 | 100 (4/4) | NA (0/0) | 0.0 (0/3) | 0.0 (0/4) | 75.0 (3/4) | NA (0/0) | 0.0 (0/3) | 25.0 (1/4) | |
| meropenem | 4 | 0 | 0 | 100 (4/4) | NA (0/0) | 0.0 (0/4) | 0.0 (0/4) | 100 (4/4) | NA (0/0) | 0.0 (0/4) | 0.0 (0/4) | |
| amikacin | 4 | 0 | 0 | 100 (4/4) | NA (0/0) | 0.0 (0/4) | 0.0 (0/4) | 100 (4/4) | NA (0/0) | 0.0 (0/4) | 0.0 (0/4) | |
| gentamicin | 4 | 0 | 0 | 100 (4/4) | NA (0/0) | 0.0 (0/4) | 0.0 (0/4) | 100 (4/4) | NA (0/0) | 0.0 (0/4) | 0.0 (0/4) | |
| ciprofloxacin | 4 | 0 | 0 | 100 (4/4) | NA (0/0) | 0.0 (0/4) | 0.0 (0/4) | 100 (4/4) | NA (0/0) | 0.0 (0/4) | 0.0 (0/4) | |
| colistin | 4 | 0 | 0 | 100 (4/4) | NA (0/0) | 0.0 (0/4) | 0.0 (0/4) | 100 (4/4) | NA (0/0) | 0.0 (0/4) | 0.0 (0/4) | |
| Proteus mirabilis | 3 | |||||||||||
| TZP | 3 | 0 | 0 | 100 (3/3) | NA (0/0) | 0.0 (0/3) | 0.0 (0/3) | 100 (3/3) | NA (0/0) | 0.0 (0/3) | 0.0 (0/3) | |
| cefepime | 1 | 1 | 1 | 66.6 (2/3) | 0.0 (0/1) | 0.0 (0/1) | 33.3 (1/3) | 66.6 (2/3) | 0.0 (0/1) | 0.0 (0/1) | 33.3 (1/3) | |
| ceftazidime | 1 | 0 | 2 | 100 (3/3) | 0.0 (0/2) | 0.0 (0/1) | 0.0 (0/3) | 100 (3/3) | 0.0 (0/2) | 0.0 (0/1) | 0.0 (0/3) | |
| ertapenem | 3 | 0 | 0 | 100 (3/3) | NA (0/0) | 0.0 (0/3) | 0.0 (0/3) | 100 (3/3) | NA (0/0) | 0.0 (0/3) | 0.0 (0/3) | |
| meropenem | 3 | 0 | 0 | 100 (3/3) | NA (0/0) | 0.0 (0/3) | 0.0 (0/3) | 100 (3/3) | NA (0/0) | 0.0 (0/3) | 0.0 (0/3) | |
| amikacin | 1 | 1 | 1 | 66.6 (2/3) | 0.0 (0/1) | 0.0 (0/1) | 33.3 (1/3) | 100 (3/3) | 0.0 (0/1) | 0.0 (0/1) | 0.0 (0/3) | |
| gentamicin | 1 | 0 | 2 | 100 (3/3) | 0.0 (0/2) | 0.0 (0/1) | 0.0 (0/3) | 100 (3/3) | 0.0 (0/2) | 0.0 (0/1) | 0.0 (0/3) | |
| ciprofloxacin | 1 | 0 | 2 | 100 (3/3) | 0.0 (0/2) | 0.0 (0/1) | 0.0 (0/3) | 100 (3/3) | 0.0 (0/2) | 0.0 (0/1) | 0.0 (0/3) | |
| S. marcescens | 2 | |||||||||||
| TZP | 1 | 0 | 1 | 100 (2/2) | 0.0 (0/1) | 0.0 (0/1) | 0.0 (0/2) | 50.0 (1/2) | 0.0 (0/1) | 0.0 (0/1) | 50.0 (1/2) | |
| cefepime | 2 | 0 | 0 | 100 (2/2) | NA (0/0) | 0.0 (0/2) | 0.0 (0/2) | 100 (2/2) | NA (0/0) | 0.0 (0/2) | 0.0 (0/2) | |
| ceftazidime | 2 | 0 | 0 | 100 (2/2) | NA (0/0) | 0.0 (0/2) | 0.0 (0/2) | 100 (2/2) | NA (0/0) | 0.0 (0/2) | 0.0 (0/2) | |
| ertapenem | 2 | 0 | 0 | 100 (2/2) | NA (0/0) | 0.0 (0/2) | 0.0 (0/2) | 100 (2/2) | NA (0/0) | 0.0 (0/2) | 0.0 (0/2) | |
| meropenem | 2 | 0 | 0 | 100 (2/2) | NA (0/0) | 0.0 (0/2) | 0.0 (0/2) | 100 (2/2) | NA (0/0) | 0.0 (0/2) | 0.0 (0/2) | |
| amikacin | 2 | 0 | 0 | 100 (2/2) | NA (0/0) | 0.0 (0/2) | 0.0 (0/2) | 100 (2/2) | NA (0/0) | 0.0 (0/2) | 0.0 (0/2) | |
| gentamicin | 2 | 0 | 0 | 100 (2/2) | NA (0/0) | 0.0 (0/2) | 0.0 (0/2) | 100 (2/2) | NA (0/0) | 0.0 (0/2) | 0.0 (0/2) | |
| ciprofloxacin | 2 | 0 | 0 | 100 (2/2) | NA (0/0) | 0.0 (0/2) | 0.0 (0/2) | 100 (2/2) | NA (0/0) | 0.0 (0/2) | 0.0 (0/2) | |
| Total | 62 | 332 | 18 | 155 | 92.7 (467/504) | 3.9 (6/154) | 2.7 (9/332) | 4.4 (22/504) | 91.7 (463/505) | 1.9 (3/155) | 1.2 (4/332) | 6.9 (35/505) |
NA, not applicable; S, susceptible; I, intermediate; R, resistant; TZP, piperacillin/tazobactam.
a
Values in parentheses are the number of results with same categorical interpretation as the reference BMD results/total number of test results. The Accelerate Pheno™ system did not provide AST results for the cefepime/K. pneumoniae combination (n = 1).