Table 3.
Susceptibility of 120 Escherichia coli clinical isolates to alternative antimicrobial agents in relation to ST131 status and resistance groupa
| Agentb | Phenotype | No. (%) of isolates with phenotyped |
P valuee |
|||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Total (n = 120) | FQ-S, ESC-S (group 1) |
FQ-R, ESC-S (group 2) |
FQ-R, ESC-R (group 3) |
ST131 vs. other |
Group 1 vs. 2 vs. 3, otherc | |||||||
| ST131 | Other | ST131 | Other | ST131 | Other | FQ-S, ESC-S | FQ-R, ESC-S | ESC-R, FQ-R | ||||
| Azithromycin | S | 45 (30) | 9 (45) | 13 (65) | 8 (40) | 6 (30) | 6 (30) | 3 (15) | 0.004 | |||
| S or I | 68 (57) | 11 (55) | 18 (90) | 12 (60) | 11 (55) | 10 (50) | 6 (30) | 0.03 | <0.001 | |||
| Doxycycline | S | 68 (57) | 14 (70) | 15 (75) | 15 (75) | 7 (35) | 12 (60) | 5 (25) | 0.03 | 0.05 | 0.005 | |
| S or I | 90 (75) | 18 (90) | 16 (80) | 20 (100) | 11 (55) | 17 (85) | 8 (40) | 0.001 | 0.008 | 0.04 | ||
| Minocycline | S | 81 (68) | 17 (85) | 15 (75) | 16 (80) | 9 (45) | 18 (90) | 6 (30) | 0.048 | <0.001 | 0.02 | |
| S or I | 99 (83) | 18 (90) | 16 (80) | 20 (100) | 15 (75) | 19 (95) | 11 (55) | 0.047 | 0.008 | |||
| Chloramphenicol | S | 73 (61) | 13 (65) | 16 (80) | 12 (60) | 8 (40) | 13 (65) | 11 (55) | 0.04 | |||
| S or I | 106 (88) | 17 (85) | 19 (95) | 19 (95) | 17 (85) | 18 (90) | 16 (80) | |||||
| Fosfomycin | S | 118 (98) | 20 (100) | 20 (100) | 19 (95) | 20 (100) | 19 (95) | 20 (100) | ||||
| S or I | 119 (99) | 20 (100) | 20 (100) | 19 (95) | 20 (100) | 20 (100) | 20 (100) | |||||
a
FQ-S and FQ-R, fluoroquinolone resistant and susceptible; ESC-S and ESC-R, extended-spectrum-cephalosporin resistant and susceptible.
b
Agents shown are those with ≥1 susceptible (S) or intermediate (I) isolate. All isolates were resistant to rifampin.
c
No significant between-group susceptibility differences were found for ST131 isolates.
d
For each group, n = 40.
e
P values of ≤0.05 (determined by Fisher's exact test) are shown.