Table 4.
Summary of P. aeruginosa isolates from SMART (N = 1200) NS to IMI/RELa,b
| MICc (μg/mL) | N | Class A | Class B | Class C | ||||
|---|---|---|---|---|---|---|---|---|
| PER | GES | VEB | Other ESBL | KPC | Any MBL | AmpC onlyd | ||
| 4 | 313 | 12 (4%) | 9 (3%) | 18 (6%) | 8 (3%) | 3 (1%) | 9 (3%) | 254 (81%) |
| 8 | 239 | 4 (2%) | 49 (21%) | 7 (3%) | 3 (1%) | 5 (2%) | 29 (12%) | 142 (59%) |
| 16 | 128 | – | 37 (29%) | 1 (1%) | 3 (2%) | 9 (7%) | 31 (24%) | 47 (37%) |
| 32 | 84 | – | 26 (31%) | – | – | 6 (7%) | 36 (43%) | 16 (19%) |
| 64 | 404 | – | 12 (3%) | 1 (< 1%) | – | 9 (2%) | 370 (92%) | 12 (3%) |
| 128 | 14 | – | – | – | – | – | 14 (100%) | – |
| > 128 | 18 | – | – | – | – | – | 17 (94%) | 1 (6%) |
| Total number of isolates | 16 | 133 | 27 | 14 | 32 | 506 | 472 | |
ESBL extended-spectrum β-lactamase, IMI/REL imipenem/relebactam, KPC Klebsiella pneumoniae carbapenemase, MBL metallo-β-lactamase, MIC minimum inhibitory concentration, NS non-susceptible
aClass D enzymes were not detected in any of the isolates collected
bIncludes SMART 2009, 2011, 2015, and 2016 data. Approximately 100 isolates possessed more than one acquired β-lactamase. For purposes of this table, each of these isolates was only counted once; the specific category each isolate was assigned to was based on the following algorithm: MBL > KPC > GES > other ESBL
cImipenem minimum inhibitory concentration in the presence of 4 μg/mL of relebactam
dIsolates that only encoded AmpC, and not any of the other studied β-lactamases. All 472 isolates contained a gene for chromosomal PDC and 2 isolates also that contained a gene for a plasmid-borne AmpC (ie, FOX-14 and DHA-1); both of these isolates had an imipenem/relebactam MIC of 8 μg/mL