Table 3. Antibiotic susceptibilities of bla NDM-1-positive E. cloacae and transconjugants (μg/mL).
| Isolate no. a | Antibiotics b | |||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| TZP | CAZ | FEP | IPM | ETP | CIP | LEV | GEN | AMK | SXT | ATM | CHL | TET | FOS | TGC | CST | |
| ECL-2 | >256 | >256 | >256 | 32 | >32 | 1 | 1 | >256 | >256 | >320 | >256 | 64 | >256 | 32 | 2 | 0.5 |
| ECL-4 | >256 | >256 | >256 | 64 | >32 | 16 | >32 | 8 | 16 | >320 | >256 | 32 | 128 | 64 | 16 | 0.5 |
| ECL-27 | >256 | >256 | >256 | >64 | >32 | >32 | 16 | 64 | 2 | >320 | >256 | 64 | >256 | 16 | 3 | 1 |
| ECL-36 | >256 | >256 | >256 | 32 | >32 | <0.25 | <0.25 | 32 | <2 | >320 | 256 | 8 | 4 | 8 | 2 | 1 |
| ECL-37 | >256 | >256 | >256 | 16 | 32 | 16 | >32 | >256 | >256 | >320 | >256 | 32 | 128 | 64 | 3 | 1 |
| ECL-62 | >256 | >256 | >256 | 64 | 32 | 16 | 32 | >256 | >256 | >320 | >256 | 256 | >256 | >512 | 4 | 1 |
| ECL-ZMD10 | 64 | >256 | >256 | 8 | 32 | >32 | >32 | >256 | >256 | >320 | 256 | 256 | 256 | 128 | 1 | 1 |
| ECL-ZMD12 | >256 | >256 | >256 | 8 | 32 | >32 | >32 | >256 | >256 | >320 | >256 | 256 | 256 | 32 | 3 | 2 |
| E. coli Transconjugant Strains | ||||||||||||||||
| ECL-2-J53 | >256 | >256 | >256 | 32 | 32 | 1 | 0.5 | 64 | 64 | >320 | 128 | 8 | 64 | 16 | 1 | 0.5 |
| ECL-4-J53 | >256 | >256 | >256 | 32 | 32 | 16 | 32 | 2 | 8 | >320 | 128 | 8 | 32 | 16 | 4 | 0.5 |
| ECL-27-J53 | >256 | >256 | >256 | 32 | >32 | 16 | 8 | 16 | 2 | >320 | >256 | 32 | 64 | 8 | 1.5 | 1 |
| ECL-36-J53 | 64 | >256 | >256 | 32 | >32 | <0.25 | <0.25 | 32 | <2 | >320 | <1 | 8 | 8 | 8 | 1.5 | 1 |
| ECL-37-J53 | >256 | >256 | >256 | 16 | 32 | 16 | 32 | 16 | >64 | >320 | >256 | 16 | 128 | 32 | 1.5 | 1 |
| ECL-62-J53 | >256 | >256 | >256 | 32 | 16 | 16 | 32 | 64 | >64 | >320 | >256 | 32 | 128 | >512 | 2 | 1 |
| ECL-ZMD10-J53 | 64 | >256 | >256 | 4 | 16 | 32 | 16 | >256 | >256 | >320 | 128 | 256 | 256 | 128 | 1 | 0.5 |
| ECL-ZMD12-J53 | >256 | >256 | >256 | 8 | 32 | 32 | 32 | >256 | 16 | <20 | >256 | 256 | 256 | 32 | 3 | 1 |
| EC J53 | <4 | <1 | <1 | <1 | <0.5 | <0.25 | <0.25 | <1 | <2 | <20 | <1 | 8 | 2 | 2 | 0.25 | 0.5 |
a ECL, E. cloacae strains; For the transconjugants, all were E. coli J53 harboring plasmids from the respective clinical isolates. All of the bla NDM-1-positive isolates were multidrug-resistant (MDR) strains, the XDR isolates are highlighted in bold type.
b Abbreviations used:TZP, piperacillin/tazobactam (0.5/4-256/4); CAZ, ceftazidime (0.03–256); FEP, cefepime (0.015–256); IPM, imipenem(0.06–64); ETP, ertapenem(0.004–32); CIP, ciprofloxacin (0.004–32); LEV, levofloxacin (0.008–32); GEN, gentamicin (0.25–256); AMK, amikacin (0.5–256); ATM, aztreonam (0.06–256); CHL, chloroamphenicol (0.016–256); TET, tetracycline (0.016–256); FOS, fosfomycin (0.25–512); TGC, tigecycline (0.016–256); CST, colistin (0.016–256). The numbers in parentheses indicate the test range (μg/mL) for each agent.