Table 4.
Antimicrobials, dilution ranges, and cut-off values used for MIC determination of Campylobacter.
| Antimicrobials | MIC breakpoints (µg/mL) | Distribution % of MIC (µg/mL) | MIC50 (µg/mL) | MIC90 (µg/mL) | Number of resistant isolates (%) | Number of resistant C. jejuni (%) | Number of resistant C. coli (%) | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| S | R | 0.06 | 0.12 | 0.25 | 0.5 | 1 | 2 | 4 | 8 | 16 | 32 | 64 | ||||||
| Chloramphenicol | ≤8 | ≥32 | 76.5 | 21 | 1.2 | 0 | 1.3 | 2 | 4 | 9 (1.2%) | 8 (1.71%) | 1 (0.34%) | ||||||
|
| ||||||||||||||||||
| Ciprofloxacin | ≤1 | ≥4 | 7.2 | 0.4 | 0 | 0.1 | 0 | 1.9 | 90.4 | 4 | 4 | 696 (90.4%) | 424 (90.79%) | 272 (93.15%) | ||||
|
| ||||||||||||||||||
| Erythromycin | ≤0.5 | ≥8 | 72 | 8.5 | 1.2 | 0.4 | 0.3 | 0.5 | 17.1 | 0.5 | 32 | 139 (18%) | 29 (6.20%) | 110 (41.98%)* | ||||
|
| ||||||||||||||||||
| Gentamicin | ≤4 | ≥16 | 39 | 14.3 | 31 | 13.3 | 1.6 | 0.2 | 0.3 | 0.3 | 0.25 | 1 | 2 (0.3%) | 2 (0.42%) | 0 | |||
|
| ||||||||||||||||||
| Nalidixic acid | ≤16 | ≥32 | 6.6 | 0.7 | 0.7 | 1.6 | 8.4 | 82 | 64 | 64 | 697 (90%) | 428 (91.64%) | 269 (92.12%) | |||||
|
| ||||||||||||||||||
| Streptomycin | ≤2 | ≥8 | 66.5 | 18.2 | 14.3 | 0.4 | 0.6 | 1 | 4 | 8 (1%) | 7 (0.14%) | 1 (0.34%) | ||||||
|
| ||||||||||||||||||
| Tetracycline | ≤4 | ≥16 | 33 | 1.3 | 0.2 | 0.5 | 0.2 | 0.8 | 64 | 16 | 16 | 492 (64%) | 272 (58.24%) | 220 (75.34%)** | ||||
S = sensible, R = resistant.
*Statistically significant versus C. jejuni group (P < 0.05, χ 2 test), **statistically significant versus C. jejuni group (P ≤ 0.01, χ 2 test).