Table 1.
MIC distributions for eight broad-spectrum β-lactams tested against 499 KPC-producing Enterobacteriaceae isolates collected in the SENTRY Antimicrobial Surveillance Program and MYSTIC Program USA
| Antimicrobial agent and organism (no. tested) | No. (cumulative %) inhibited at MICa (μg/ml): |
|||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| ≤0.25 | 0.5 | 1 | 2 | 4 | 8 | 16 | 32 | 64 | >64b | |
| Aztreonam | ||||||||||
| All species (408) | 1 | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 3 (0.7) | 3 (1.5) | —c | — | 402 (100.0) |
| K. pneumoniae (306) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 1 (0.3) | 2 (1.0) | — | — | 303 (100.0) |
| Non-K. pneumoniae (102) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 2 (2.0) | 1 (2.9) | — | — | 99 (100.0) |
| Cefepime | ||||||||||
| All species (499) | 0 (0.0) | 1 (0.2) | 3 (0.8) | 10 (2.8) | 18 (6.4) | 40 (14.4) | 337 (82.0) | — | — | 90 (100.0) |
| K. pneumoniae (389) | 0 (0.0) | 1 (0.3) | 0 (0.0) | 1 (0.5) | 9 (2.8) | 20 (8.0) | 275 (78.7) | — | — | 83 (100.0) |
| Non-K. pneumoniae (110) | 0 (0.0) | 0 (0.0) | 3 (2.7) | 9 (10.9) | 9 (19.1) | 8.0 (37.3) | 62 (93.6) | — | — | 7 (100.0) |
| Ceftazidime | ||||||||||
| All species (499) | 0 (0.0) | 0 (0.0) | 2 (0.4) | 3 (1.0) | 8 (2.6) | 19 (6.4) | 28 (12.0) | — | — | 439 (100.0) |
| K. pneumoniae (389) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 1 (0.3) | 3 (1.0) | 11 (3.9) | 12 (6.9) | — | — | 362 (100.0) |
| Non-K. pneumoniae (110) | 0 (0.0) | 0 (0.0) | 2 (1.8) | 2 (3.6) | 5 (8.2) | 8 (15.5) | 16 (30.0) | — | — | 77 (100.0) |
| Ceftriaxone | ||||||||||
| All species (499) | 0 (0.0) | 0 (0.0) | 1 (0.2) | 0 (0.0) | 5 (1.2) | 8 (2.8) | — | — | — | 485 (100.0) |
| K. pneumoniae (389) | 0 (0.0) | 0 (0.0) | 1 (0.3) | 0 (0.0) | 0 (0.0) | 1 (0.5) | — | — | — | 387 (100.0) |
| Non-K. pneumoniae (110) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 5 (4.5) | 7 (10.9) | — | — | — | 98 (100.0) |
| Ertapenem | ||||||||||
| All species (481) | 0 (0.0) | 2 (0.4) | 8 (2.1) | 12 (4.6) | 34 (11.6) | 58 (23.7) | — | — | — | 367 (100.0) |
| K. pneumoniae (381) | 0 (0.0) | 1 (0.5) | 4 (1.6) | 4 (2.6) | 12 (5.8) | 27 (12.9) | — | — | — | 332 (100.0) |
| Non-K. pneumoniae (100) | 0 (0.0) | 0 (0.0) | 4 (4.0) | 8 (12.0) | 22 (34.0) | 31 (65.0) | — | — | — | 35 (100.0) |
| Imipenem | ||||||||||
| All species (497) | 0 (0.0) | 2 (0.4) | 1 (0.6) | 0 (0.0) | 54 (11.5) | 124 (36.4) | — | — | — | 316 (100.0) |
| K. pneumoniae (387) | 0 (0.0) | 2 (0.5) | 0 (0.0) | 0 (0.0) | 22 (6.2) | 89 (29.2) | — | — | — | 274 (100.0) |
| Non-K. pneumoniae (110) | 0 (0.0) | 0 (0.0) | 1 (0.9) | 0 (0.0) | 32 (30.0) | 35 (61.8) | — | — | — | 42 (100.0) |
| Meropenem | ||||||||||
| All species (499) | 1 (0.2) | 8 (1.8) | 6 (3.0) | 29 (8.8) | 56 (20.0) | 76 (35.3) | — | — | — | 323 (100.0) |
| K. pneumoniae (389) | 1 (0.3) | 5 (1.5) | 3 (2.3) | 11 (5.1) | 20 (10.3) | 51 (23.4) | — | — | — | 298 (100.0) |
| Non-K. pneumoniae (110) | 0 (0.0) | 3 (2.7) | 3 (5.5) | 18 (21.8) | 36 (54.5) | 25 (77.3) | — | — | — | 25 (100.0) |
| Piperacillin-tazobactam | ||||||||||
| All species (499) | 0 (0.0) | 0 (0.0) | 0 (0.0) | (0.0) | 0 (0.0) | 3 (0.6) | 0 (0.0) | 3 (1.2) | 13 (3.8) | 480 (100.0) |
| K. pneumoniae (389) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 3 (0.8) | 0 (0.0) | 2 (1.3) | 3 (2.1) | 381 (100.0) |
| Non-K. pneumoniae (110) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 1 (0.9) | 10 (10.0) | 99 (100.0) |
a
Susceptible MIC ranges by CLSI criteria are highlighted in gray; EUCAST susceptibility MIC ranges are in boldface.
b
Greater than the highest dilution tested.
c
—, untested concentration.