TABLE 4.
Organism (no. of isolates) | Antibiotic | MIC (μg/ml)
|
||
---|---|---|---|---|
Range | 50% | 90% | ||
All isolates (272) | Ceftazidime | 2->64 | 32 | >64 |
Cefotaxime | ≤4->32 | >32 | >32 | |
Ceftriaxone | ≤4->32 | >32 | >32 | |
Cefepime | ≤2->16 | 8 | >16 | |
Imipenem | ≤0.12-32 | 0.25 | 1 | |
Piperacillin-tazobactam | ≤8->64 | ≤8 | >64 | |
Tobramycin | ≤0.25->32 | 32 | >32 | |
Levofloxacin | ≤0.12->16 | 8 | >16 | |
Minocycline | ≤0.12->64 | 8 | 64 | |
Tigecycline | 0.12-16 | 0.5 | 2 | |
All E. coli isolates (98) | Ceftazidime | 2->64 | 32 | >64 |
Cefotaxime | ≤4->32 | >32 | >32 | |
Ceftriaxone | ≤4->32 | >32 | >32 | |
Cefepime | ≤2->16 | 16 | >16 | |
Imipenem | ≤0.12-0.5 | ≤0.12 | 0.25 | |
Piperacillin-tazobactam | ≤8->64 | ≤8 | 16 | |
Tobramycin | ≤0.25->32 | 32 | >32 | |
Levofloxacin | ≤0.12->16 | 16 | >16 | |
Minocycline | 1->64 | 4 | 32 | |
Tigecycline | 0.12-2 | 0.25 | 0.5 | |
All K. pneumoniae isolates (153) | Ceftazidime | 2->64 | 32 | >64 |
Cefotaxime | ≤4->32 | >32 | >32 | |
Ceftriaxone | ≤4->32 | >32 | >32 | |
Cefepime | ≤2->16 | 8 | >16 | |
Imipenem | ≤0.12-32 | 0.25 | 1 | |
Piperacillin-tazobactam | ≤4->64 | 16 | >64 | |
Tobramycin | ≤0.25->32 | 32 | >32 | |
Levofloxacin | ≤0.12->16 | 2 | >16 | |
Minocycline | ≤0.12->64 | 4 | 64 | |
Tigecycline | 0.25-8 | 0.5 | 2 | |
All P. mirabilis isolates (21) | Ceftazidime | 2->64 | 64 | >64 |
Cefotaxime | ≤0.25->32 | 32 | >32 | |
Ceftriaxone | ≤1-64 | 8 | 32 | |
Cefepime | ≤1->16 | 2 | >16 | |
Imipenem | 0.5-4 | 2 | 4 | |
Piperacillin-tazobactam | ≤4->64 | 8 | >64 | |
Tobramycin | 0.5->32 | 8 | >32 | |
Levofloxacin | ≤0.12->16 | 8 | >16 | |
Minocycline | 16->64 | 64 | >64 | |
Tigecycline | 0.5-16 | 2 | 16 | |
E. coli blaSHVa (7) | Ceftazidime | 16->64 | NAb | NA |
Cefotaxime | ≤4-32 | NA | NA | |
Ceftriaxone | ≤4-32 | NA | NA | |
Cefepime | ≤2-4 | NA | NA | |
Imipenem | ≤0.12-0.5 | NA | NA | |
Piperacillin-tazobactam | ≤4->64 | NA | NA | |
Tobramycin | ≤0.25->32 | NA | NA | |
Levofloxacin | ≤0.12->16 | NA | NA | |
Minocycline | 2->64 | NA | NA | |
Tigecycline | 0.12-2 | NA | NA | |
E. coli blaCTX, single determinant (33) | Ceftazidime | 2->64 | 16 | 64 |
Cefotaxime | ≤4->32 | >32 | >32 | |
Ceftriaxone | ≤4->32 | >32 | >32 | |
Cefepime | ≤2->16 | 16 | >16 | |
Imipenem | ≤0.12-0.5 | ≤0.12 | 0.25 | |
Piperacillin-tazobactam | ≤8->64 | ≤8 | 32 | |
Tobramycin | 0.5->32 | 32 | >32 | |
Levofloxacin | ≤0.12->16 | 16 | >16 | |
Minocycline | 1->64 | 4 | 32 | |
Tigecycline | 0.12-2 | 0.25 | 0.5 | |
E. coli blaCTX, multiple determinants (18) | Ceftazidime | 2->64 | 32 | 64 |
Cefotaxime | 32->32 | >32 | >32 | |
Ceftriaxone | >32 | >32 | >32 | |
Cefepime | 4->16 | 16 | >16 | |
Imipenem | ≤0.12-0.25 | ≤0.12 | 0.25 | |
Piperacillin-tazobactam | ≤8-16 | ≤8 | 16 | |
Tobramycin | 0.5->32 | 32 | >32 | |
Levofloxacin | ≤0.12->16 | >16 | >16 | |
Minocycline | 2-64 | 4 | 32 | |
Tigecycline | 0.12-1 | 0.5 | 0.5 | |
E. coli blaCTX + blaSHVa (16) | Ceftazidime | 2->64 | 16 | 64 |
Cefotaxime | 32->32 | >32 | >32 | |
Ceftriaxone | >32 | >32 | >32 | |
Cefepime | ≤2->16 | 16 | >16 | |
Imipenem | ≤0.12-0.25 | ≤0.12 | 0.25 | |
Piperacillin-tazobactam | ≤4-16 | <4 | 8 | |
Tobramycin | 0.5->32 | 32 | >32 | |
Levofloxacin | ≤0.12->16 | 16 | >16 | |
Minocycline | 1-32 | 4 | 16 | |
Tigecycline | 0.25-0.5 | 0.25 | 0.5 | |
E. coli blaAmpC (5) | Ceftazidime | 4-64 | NA | NA |
Cefotaxime | 4-32 | NA | NA | |
Ceftriaxone | 4-32 | NA | NA | |
Cefepime | ≤2 | NA | NA | |
Imipenem | 0.12-0.25 | NA | NA | |
Piperacillin-tazobactam | ≤4-8 | NA | NA | |
Tobramycin | 1-8 | NA | NA | |
Levofloxacin | ≤0.12->16 | NA | NA | |
Minocycline | 1->64 | NA | NA | |
Tigecycline | 0.25-0.5 | NA | NA | |
E. coli blaAmpC + ESBL (15) | Ceftazidime | 16->32 | >32 | >32 |
Cefotaxime | 16->32 | >32 | >32 | |
Ceftriaxone | 16->32 | >32 | >32 | |
Cefepime | 4->16 | 16 | >16 | |
Imipenem | ≤0.12-0.5 | 0.25 | 0.5 | |
Piperacillin-tazobactam | ≤8-32 | ≤8 | 16 | |
Tobramycin | 1->32 | 16 | >32 | |
Levofloxacin | ≤0.12->16 | 16 | >16 | |
Minocycline | 1->64 | 4 | >64 | |
Tigecycline | 0.12-1 | 0.25 | 0.5 | |
K. pneumoniae blaSHV,a single determinant (14) | Ceftazidime | 2->64 | 8 | >64 |
Cefotaxime | 2->32 | 16 | >32 | |
Ceftriaxone | ≤1->32 | 8 | >32 | |
Cefepime | ≤2->16 | ≤2 | >16 | |
Imipenem | 0.12-16 | 0.25 | 1 | |
Piperacillin-tazobactam | ≤4->64 | 32 | >64 | |
Tobramycin | 0.5->32 | 16 | >32 | |
Levofloxacin | ≤0.12->16 | 0.5 | 16 | |
Minocycline | 0.5-64 | 4 | 64 | |
Tigecycline | 0.25-2 | 0.5 | 1 | |
K. pneumoniae blaSHV,a multiple determinants (3) | Ceftazidime | 16->64 | NA | NA |
Cefotaxime | 2-32 | NA | NA | |
Ceftriaxone | 2-32 | NA | NA | |
Cefepime | ≤2-16 | NA | NA | |
Imipenem | ≤0.12-0.25 | NA | NA | |
Piperacillin-tazobactam | ≤4->64 | NA | NA | |
Tobramycin | 0.5-16 | NA | NA | |
Levofloxacin | ≤0.12-0.5 | NA | NA | |
Minocycline | 2->64 | NA | NA | |
Tigecycline | 0.5-8 | NA | NA | |
K. pneumoniae blaCTX, single determinant (44) | Ceftazidime | 4->64 | 32 | >64 |
Cefotaxime | 16->32 | >32 | >32 | |
Ceftriaxone | 16->32 | >32 | >32 | |
Cefepime | ≤2->16 | 16 | >16 | |
Imipenem | ≤0.12-1 | 0.25 | 0.5 | |
Piperacillin-tazobactam | ≤4->64 | 16 | >64 | |
Tobramycin | ≤0.25->32 | 16 | >32 | |
Levofloxacin | ≤0.12->16 | 4 | >16 | |
Minocycline | ≤0.12->64 | 4 | 32 | |
Tigecycline | 0.25-4 | 1 | 2 | |
K. pneumoniae blaCTX, multiple determinants (20) | Ceftazidime | 2->64 | 32 | >64 |
Cefotaxime | 1->32 | >32 | >32 | |
Ceftriaxone | ≤1->32 | >32 | >32 | |
Cefepime | ≤2->16 | 16 | >16 | |
Imipenem | ≤0.12-1 | 0.25 | 0.5 | |
Piperacillin-tazobactam | ≤4->64 | 16 | >64 | |
Tobramycin | ≤0.25->32 | 32 | >32 | |
Levofloxacin | ≤0.12->16 | 4 | 16 | |
Minocycline | 2-32 | 4 | 16 | |
Tigecycline | 0.25-2 | 0.5 | 1 | |
K. pneumoniae blaSHVa + blaCTX (39) | Ceftazidime | 4->64 | 64 | >64 |
Cefotaxime | ≤0.25->32 | >32 | >32 | |
Ceftriaxone | 8->32 | >32 | >32 | |
Cefepime | ≤2->16 | 8 | >16 | |
Imipenem | ≤0.12-4 | 0.25 | 0.5 | |
Piperacillin-tazobactam | ≤4->64 | 8 | >64 | |
Tobramycin | 8->32 | 32 | >32 | |
Levofloxacin | ≤0.12->16 | 0.5 | >16 | |
Minocycline | 1->64 | 8 | 64 | |
Tigecycline | 0.25-2 | 0.5 | 2 | |
K. pneumoniae ESBL + blaAmpC (7) | Ceftazidime | 4->64 | NA | NA |
Cefotaxime | 1->32 | NA | NA | |
Ceftriaxone | 2->32 | NA | NA | |
Cefepime | ≤2->16 | NA | NA | |
Imipenem | ≤0.06-1 | NA | NA | |
Piperacillin-tazobactam | 8->64 | NA | NA | |
Tobramycin | ≤0.25->32 | NA | NA | |
Levofloxacin | 2->16 | NA | NA | |
Minocycline | 4->64 | NA | NA | |
Tigecycline | 0.5-4 | NA | NA | |
K. pneumoniae blaDHA (4) | Ceftazidime | 64->64 | NA | NA |
Cefotaxime | 2->32 | NA | NA | |
Ceftriaxone | ≤1->32 | NA | NA | |
Cefepime | ≤2-16 | NA | NA | |
Imipenem | 0.5-2 | NA | NA | |
Piperacillin-tazobactam | 8->64 | NA | NA | |
Tobramycin | 16->32 | NA | NA | |
Levofloxacin | 1->16 | NA | NA | |
Minocycline | 4-64 | NA | NA | |
Tigecycline | 0.5-1 | NA | NA | |
P. mirabilis ESBL, single determinant (6) | Ceftazidime | 2->64 | NA | NA |
Cefotaxime | ≤0.25->64 | NA | NA | |
Ceftriaxone | ≤1-32 | NA | NA | |
Cefepime | ≤1->16 | NA | NA | |
Imipenem | 0.5-4 | NA | NA | |
Piperacillin-tazobactam | ≤4->64 | NA | NA | |
Tobramycin | 0.5->32 | NA | NA | |
Levofloxacin | ≤0.12-16 | NA | NA | |
Minocycline | 16->64 | NA | NA | |
Tigecycline | 2-16 | NA | NA | |
P. mirabilis ESBL, multiple determinants (7) | Ceftazidime | 2->64 | NA | NA |
Cefotaxime | 8->64 | NA | NA | |
Ceftriaxone | 2-64 | NA | NA | |
Cefepime | ≤1->16 | NA | NA | |
Imipenem | 2-4 | NA | NA | |
Piperacillin-tazobactam | ≤4->64 | NA | NA | |
Tobramycin | 4->32 | NA | NA | |
Levofloxacin | 2->16 | NA | NA | |
Minocycline | 16->64 | NA | NA | |
Tigecycline | 0.5-16 | NA | NA | |
P. mirabilis blaAmpC (3) | Ceftazidime | 64->64 | NA | NA |
Cefotaxime | 16->32 | NA | NA | |
Ceftriaxone | 8-16 | NA | NA | |
Cefepime | 2->16 | NA | NA | |
Imipenem | 1-2 | NA | NA | |
Piperacillin-tazobactam | 8-64 | NA | NA | |
Tobramycin | 4->32 | NA | NA | |
Levofloxacin | 4->16 | NA | NA | |
Minocycline | 16-64 | NA | NA | |
Tigecycline | 2-4 | NA | NA |
Thirty-one percent of blaSHV genes were analyzed by pyrosequencing; and sequence information was derived only for nucleotides encoding residues at positions 35, 238, and 240. Therefore, these genes encode critical residues for the ESBL phenotype but have not been fully sequenced for unambiguous determination of the blaSHV derivative.
NA, not applicable (less than 10 isolates were analyzed).