Table 3.
Relationship between ESBL production and antimicrobial susceptibility
| Bacteriuma | ESBL genotype (no. of isolates) | No. of isolates with the indicated susceptibility pattern | Cephalosporin susceptibility patternb |
||
|---|---|---|---|---|---|
| Ceftazidime | Cefepime | Aztreonam | |||
| E. coli (n = 155) | CTX-M-9 group (99) | 22 | S | S | S |
| 13 | R | R | R | ||
| 12 | S | S | R | ||
| 11 | I | R | R | ||
| 11 | S | S | I | ||
| 10 | S | I | R | ||
| 5 | S | I | I | ||
| 4 | R | S | R | ||
| 3 | S | R | R | ||
| 3 | I | I | R | ||
| 3 | I | S | R | ||
| 2 | R | I | R | ||
| CTX-M-1 group (40) | 20 | R | R | R | |
| 8 | R | I | R | ||
| 4 | S | S | R | ||
| 4 | R | S | R | ||
| 1 | I | I | R | ||
| 1 | I | S | I | ||
| 1 | I | S | R | ||
| 1 | S | I | R | ||
| CTX-M-1 group + CTX-M-9 group (13) | 5 | R | R | R | |
| 3 | R | I | R | ||
| 2 | S | I | R | ||
| 1 | R | S | R | ||
| 1 | S | S | R | ||
| 1 | I | R | R | ||
| CTX-M-9 group + CTX-M-25 group (3) | 2 | R | R | R | |
| 1 | S | S | S | ||
| K. pneumoniae | CTX-M-1 group (67) (n = 150) | 57 | R | R | R |
| 6 | R | I | R | ||
| 1 | R | S | R | ||
| 1 | S | S | I | ||
| 1 | I | R | R | ||
| 1 | S | S | S | ||
| CTX-M-9 group (30) | 7 | R | I | R | |
| 6 | S | S | I | ||
| 4 | R | R | R | ||
| 3 | I | R | R | ||
| 3 | R | S | R | ||
| 2 | I | I | R | ||
| 2 | S | S | R | ||
| 1 | S | I | R | ||
| 1 | I | S | I | ||
| 1 | S | S | S | ||
| CTX-M-1 group + SHV (16) | 13 | R | R | R | |
| 1 | R | I | R | ||
| 1 | R | S | R | ||
| 1 | S | S | I | ||
| CTX-M-9 group + SHV (13) | 9 | R | I | R | |
| 2 | R | R | R | ||
| 2 | R | S | R | ||
| CTX-M-1 group + CTX-M-9 group (12) | 11 | R | R | R | |
| 1 | I | S | R | ||
| SHV alone (7) | 5 | R | S | R | |
| 2 | R | I | R | ||
| CTX-M-1 group + CTX-M-9 group + SHV (5) | 3 | R | R | R | |
| 2 | R | I | R | ||
| P. mirabilis (n = 58) | CTX-M-9 group (51) | 44 | S | S | S |
| 5 | S | I | S | ||
| 1 | S | R | S | ||
| 1 | I | I | S | ||
| CTX-M-1 group (3) | 2 | S | S | S | |
| 1 | R | I | R | ||
| CTX-M-1 group CTX-M-9 group (4) | 2 | S | S | S | |
| 2 | I | S | S | ||
a
Genotypes could not be determined in 3 strains of E. coli, 14 of K. pneumoniae, and 2 of P. mirabilis.
b
S, susceptible; R, resistant; I, intermediate.