Volume 12, Number 8—August 2006
Research
Carbapenem Resistance in Klebsiella pneumoniae Not Detected by Automated Susceptibility Testing
Table 1
Carbapenem susceptibility and strain typing results for isolates tested in the study*
Organism | Imipenem broth microdilution MIC† (μg/mL) and CLSI interpretation | Meropenem broth microdilution MIC (μg/mL) and CLSI interpretation | PFGE profile | Hospital identification no. |
---|---|---|---|---|
1 Klebsiella pneumoniae | 8 I | 16 R | A | 1 |
2 K. pneumoniae | 16 R | >16 R | A | 1 |
3 K. pneumoniae | 16 R | 16 R | A | 2 |
4 K. pneumoniae | 8 I | 8 I | A | 2 |
5 K. pneumoniae | 16 R | >16 R | A | 2 |
6 K. pneumoniae | 16 R | 16 R | A | 2 |
7 K. pneumoniae | 16 R | 16 R | A | 3 |
8 K. pneumoniae | 32 R | 16 R | A | 4 |
9 K. pneumoniae | 16 R | >16 R | B | 1 |
10 K. pneumoniae | 16 R | >16 R | B | 1 |
11 K. pneumoniae | 16 R | 16 R | C | 4 |
12 K. pneumoniae | 16 R | 16 R | D | 1 |
13 K. pneumoniae | 16 R | 16 R | E | 4 |
14 K. pneumoniae | 16 R | >16 R | F | 1 |
15 K. pneumoniae | 16 R | >16 R | F1 | 4 |
K. pneumoniae 1534 (control) | 16 R | >16 R | NA | NA |
Serratia marcescens 525 (control) | >16 R | >16 R | NA | NA |
*CLSI, Clinical and Laboratory Standards Institute; PFGE, pulsed-field gel electrophoresis; NA, not applicable.†Interpretations of MIC results used CLSI criteria (18); I, intermediate; R, resistant.
References
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