Table 1.
Resistance phenotype and minimum inhibitory concentrations (in mg/L) for carbapenem-resistant Enterobacteriaceaea
| Case | Species | MER [≥4] | IPM [≥4] | DOR [≥4] | ERT [≥1] | CAZ [≥16] | TZP [≥128] | CIP [≥4] | GEN [≥16] | AMK [≥64] | TOB [≥16] | SXT [≥4/76] | SUL [≥512] | FOS [≥256] | COL [>2] | TIG [>4] | MHT |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 | Serratia marcescens | S (1) | R (>32) | S (2) | R (2) | S | S | S | S | S | S | S | S | S (12) | R (>256) | S (4) | − |
| 2 | Escherichia coli | R (16) | R (32) | R (16) | R (>32) | R | R | S | S | S | S | S | R | S (6) | S (0.38) | S (0.125) | − |
| 3 | E. coli | R (16) | R (32) | R (16) | R (>32) | R | R | R | S | I | R | S | R | S (4) | S (0.125) | S (0.5) | − |
| 4 | Klebsiella pneumoniae | R (32) | R (32) | R (32) | R (32) | R | R | R | R | R | R | R | R | R (256) | S (0.5) | S (1) | + |
| 5 | K. pneumoniae | R (16) | S (1.5) | R (4) | R (32) | R | R | I | R | S | S | R | R | R (1024) | S (1) | S (1.5) | − |
| 6 | K. pneumoniae | S (1.5) | S (0.25) | S (1) | R (12) | R | R | R | R | S | S | R | R | S (64) | S (1) | S (0.75) | − |
MER, meropenem; IPM, imipenem; DOR, doripenem; ERT, ertapenem; CAZ, ceftazidime; TZP, piperacillin/tazobactam; CIP, ciprofloxacin; GEN, gentamicin; AMK, amikacin; TOB, tobramycin; SXT, trimethoprim/sulfamethoxazole; SUL, sulfamethoxazole; FOS, fosfomycin; COL, colistin; TIG, tigecycline; MHT, Modified Hodge test; S, susceptible; I, intermediate; R, resistant.
Reported interpretation (S, I and R) and minimum inhibitory concentration breakpoints [in brackets] are per Clinical and Laboratory Standards Institute (CLSI) document M100-S21, with the exception of colistin and tigecycline where European Committee on Antimicrobial Susceptibility Testing (EUCAST) 2010 breakpoints were used.