Table 4.
Genotypic characteristics of third- and fourth-generation cephalosporin-resistant Enterobacterales strains causing infection in companion animals (n = 10).
| Household | Host | Type of infectiona | Strain code | Bacterial species | Pattern of resistanceb | Beta-lactam-resistant genes |
|---|---|---|---|---|---|---|
| PT110 | Dog | SSTI | PT110/0-D1F3E1 | Escherichia coli | AMC, AMP, C, CIP, CFL, CTX, F, FOX, TMS | blaCTX-M-65, blaTEM-1 |
| PT125 | Dog | SSTI | PT125/0-D1I3E1 | Escherichia coli | AK, AMP, CAZ, CFL, CIP, CTX, CPM, F | bla CTX-M-27 |
| PT202 | Dog | UTI | PT202/0-D1I3E1 | Escherichia coli | AMP, CIP, CFL, CTX, TMS | blaCTX-M-1, blaTEM-1 |
| PT209 | Dog | UTI | PT209/0-D1I3E1 | Escherichia coli | AMC, AMP, CAZ, CFL, CN, CTX, F, FOX, TMS | blaCMY-2, blaTEM-1 |
| PT212 | Dog | UTI | PT212/0-D1I4E1 | Escherichia coli | AMP, CAZ, CFL, CIP, CTX, FOX | bla CTX-M-15 |
| PT213 | Cat | UTI | PT213/T0-C1I3K1 | Klebsiella pneumoniae | AMC, AMP, CAZ, CFL, CN, CPM, CTX, F, FOX, TET, TMS | blaCTX-M-15, blaSHV-28, blaTEM-1 |
| PV001 | Dog | UTI | PV001G1D1U1 | Enterobacter spp. | AMC, AMP, CAZ, CFL, C, CIP, CN, CTX, F, FOX, TET, TMS | bla CMY-2 |
| PV002 | Dog | UTI | PV002V1UD1U1 | Klebsiella pneumoniae | AMC, CAZ, CIP, CFL, CN, CTX, CPM, TMS | blaCTX-M-15, blaCMY-2, blaTEM-1 |
| PV003 | Dog | UTI | PV003V1UD1K5 | Klebsiella pneumoniae | AMP, CAZ, CFL, CTX, CPM, F, TET, TMS | blaCTX-M-15, blaSHV-11, blaTEM-1 |
| PV004 | Cat | UTI | PV004V0C1I0E1 | Escherichia coli | AMP, CAZ, CFL, CIP, CTX, CPM, TET, TMS | bla CTX-M-27 |
a UTI, urinary tract infection; SSTI, skin and soft tissue infection.
b Antibiotics tested: AK, amikacin; AMC, amoxicillin/clavulanate; AMP, ampicillin; C, chloramphenicol; CAZ, ceftazidime; CFL, cephalothin; CIP, ciprofloxacin; CN, gentamicin; CTX, cefotaxime; CPM, cefepime; ETP, ertapenem; F, nitrofurantoin; FOX, cefoxitin; IMP, imipenem; MEM, meropenem; TET, tetracycline; TMS, trimethoprim/sulfamethoxazole.
Minimum inhibitory concentrations (MICs) were interpreted using the criteria of the European Committee on Antimicrobial Susceptibility Testing (EUCAST) 2024 (The European Committee on Antimicrobial Susceptibility Testing, 2024), except for amoxicillin/clavulanate, ampicillin/sulbactam, and trimethoprim/sulfamethoxazole, for which criteria from the Clinical and Laboratory Standards Institute (CLSI) were used (CLSI, 2024).