TABLE 1.
Antimicrobial agent or characteristic | Breakpoint(s) (R) | % Resistant
|
|||||
---|---|---|---|---|---|---|---|
All isolates (n = 1,604) | S. sonnei (n = 1,278) | S. flexneri (n = 295) | S. boydii (n = 18) | S. dysenteriae (n = 7) | Unknown (n = 6) | ||
Amikacin | ≥64 | 0.06 | 0.08 | 0 | 0 | 0 | 0 |
Amoxicillin-clavulanic acid | ≥32/16 | 2 | 2 | 5 | 0 | 0 | 0 |
Ampicillin | ≥32 | 78 | 79 | 76 | 0 | 71 | 100 |
Ceftiofura | ≥8 | 0.06 | 0 | 0.3 | 0 | 0 | 0 |
Ceftriaxone | ≥64 | 0 | 0 | 0 | 0 | 0 | 0 |
Cephalothin | ≥32 | 6 | 7 | 3 | 0 | 0 | 0 |
Chloramphenicol | ≥32 | 14 | 1 | 70 | 0 | 43 | 67 |
Ciprofloxacin | ≥4 | 0.06 | 0 | 0.3 | 0 | 0 | 0 |
Gentamicin | ≥16 | 0.2 | 0.2 | 0.3 | 0 | 0 | 0 |
Kanamycin | ≥64 | 0.9 | 0.8 | 1 | 0 | 0 | 0 |
Nalidixic acid | ≥32 | 1 | 1 | 2 | 6 | 0 | 0 |
Streptomycina | ≥64 | 56 | 55 | 55 | 72 | 71 | 83 |
Sulfamethoxazole | ≥512 | 47 | 45 | 54 | 78 | 71 | 50 |
Tetracycline | ≥16 | 45 | 33 | 92 | 50 | 71 | 83 |
TMP-SMX | ≥4/76 | 46 | 48 | 40 | 39 | 57 | 50 |
Ampicillin and TMP-SMX | ≥32 and ≥4/76 | 38 | 39 | 35 | 0 | 43 | 50 |
% Pansusceptible | 7 | 8 | 5 | 17 | 14 | 0 | |
% Multiresistantb | 64 | 59 | 85 | 83 | 71 | 100 |
No CLSI interpretive standards for this antimicrobial agent. The MIC for ceftiofur was based on population distributions of MICs for gram-negative isolates. The MIC of streptomycin is based on the Canadian Integrated Program for Antimicrobial Resistance (19).
Defined as resistant to two or more antimicrobial agents.