Table 3. Characteristics of all isolates of colistin-resistant Enterobacteriaceae from all study pigs.
| Colistin-resistant Enterobacteriaceae | n | ESBL-producer | Colistin MIC50/MIC90 (MIC range) | mcr-1 positive |
|---|---|---|---|---|
| E. coli | 120 (79.5%) | 119 (99.2%) | 8/>128 (4 to >128 mg/L) | 84 (70.0%) |
| K. pneumoniae | 21 (13.9%) | 21 (100%) | 16/64 (4 to >128 mg/L) | 2 (9.5%) |
| Enterobacter spp. | 5 (3.3%) | 5 (100%) | 8/16 (4 to >128 mg/L) | 0 (0.0%) |
| Citrobacter freundii | 4 (2.6%) | 4 (100%) | 8/8 (8 to >128 mg/L) | 0 (0.0%) |
| Edwardsiella tarda | 1 (0.7%) | 1 (100%) | N/A | 1 (100%) |
| All | 151 (100%) | 150 (99.3%) | 8/>128 (4 to >128 mg/L) | 87 (57.6%) |
Abbreviations: ESBL, extended spectrum beta-lactamase; MIC, minimum inhibitory concentration; mcr-1 gene, mobilized plasmid-borne colistin resistance gene; E. coli; Escherichia coli; K. pneumoniae, Klebsiella pneumoniae; N/A, not applicable.