Table 2.
In vitro activities of orally prescribed antimicrobial agents against E. coli isolated from urine specimens in clinical laboratories across Canada from 2010 to 2013a.
| E. coli isolate phenotypeb (number tested) | Antimicrobial agent | MIC interpretation | |
|---|---|---|---|
| % susceptible | % resistant | ||
| All E. coli (868) | Fosfomycin | 99.4 | 0.1 |
| Amoxicillin-clavulanate | 81.3 | 5.7 | |
| Ciprofloxacin | 77.4 | 22.5 | |
| Nitrofurantoin | 96.1 | 1.5 | |
| TMP-SMXc | 74.7 | 25.3 | |
|
| |||
| TMP-SMX-resistant (219) | Fosfomycin | 99.1 | 0 |
| Amoxicillin-clavulanate | 67.1 | 6.4 | |
| Ciprofloxacin | 51.6 | 47.9 | |
| Nitrofurantoin | 91.8 | 3.2 | |
| TMP-SMX | 0 | 100 | |
|
| |||
| Ciprofloxacin-resistant (195) | Fosfomycin | 97.9 | 0 |
| Amoxicillin-clavulanate | 66.0 | 6.7 | |
| Ciprofloxacin | 0 | 100 | |
| Nitrofurantoin | 91.3 | 4.1 | |
| TMP-SMX | 45.9 | 54.1 | |
|
| |||
| ESBL-producing (42) | Fosfomycin | 100 | 0 |
| Amoxicillin-clavulanate | 33.3 | 11.9 | |
| Ciprofloxacin | 9.5 | 90.5 | |
| Nitrofurantoin | 83.3 | 4.8 | |
| TMP-SMX | 35.7 | 64.3 | |
|
| |||
| AmpC-producing (16) | Fosfomycin | 100 | 0 |
| Amoxicillin-clavulanate | 6.3 | 87.4 | |
| Ciprofloxacin | 75.0 | 25.0 | |
| Nitrofurantoin | 100 | 0 | |
| TMP-SMX | 75.0 | 25.0 | |
|
| |||
| Multidrug-resistant (15) | Fosfomycin | 100 | 0 |
| Amoxicillin-clavulanate | 13.3 | 66.7 | |
| Ciprofloxacin | 0 | 100 | |
| Nitrofurantoin | 60.0 | 40.0 | |
| TMP-SMX | 6.7 | 93.3 | |
aData adapted from [9].
bESBL, extended-spectrum β-lactamase; AmpC, chromosomal AmpC β-lactamase; multidrug-resistant was defined as isolates resistant to ≥3 agents from different antimicrobial classes (amoxicillin-clavulanate, ciprofloxacin, nitrofurantoin, and TMP-SMX).
cTMP-SMX, trimethoprim-sulfamethoxazole.