Table 3.
Correlation of the results of disk diffusion (DD) and automated systems in susceptibility testing to the antibiotics tested: Numbers of discordances.
| Discordances between DD and the three automated systems | Discordances between the three automated systems | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| DD/Phoenix | DD/MicroScan | DD/Vitek2 | Vitek2/MicroScan | Vitek2/Phoenix | Phoenix/MicroScan | |||||||
| Antibiotics | Major* | Minor** | Major* | Minor** | Major* | Minor** | Major* | Minor** | Major* | Minor** | Major* | Minor** |
| MEM | 3 | 30 | 7 | 62 | 15 | 72 | 3 | 62 | 4 | 62 | 31 | |
| PRL | 4 | 4 | 3 | 1 | 1 | 2 | ||||||
| CAZ | 3 | 3 | 10 | 1 | 3 | 2 | 13 | 1 | 2 | 1 | 13 | |
| FEP | 9 | 41 | 4 | 43 | 7 | 34 | 1 | 16 | 3 | 16 | 1 | 20 |
| CTX | 1 | 4 | 1 | 6 | 1 | 4 | 1 | 2 | 1 | 2 | 1 | 2 |
| CIP | 1 | 17 | 7 | 9 | 9 | 14 | 11 | 19 | 15 | |||
| LEV | 1 | 25 | 24 | 1 | 24 | 21 | 22 | 17 | ||||
| CN | 7 | 8 | 4 | 5 | 5 | 3 | 1 | 5 | 5 | 6 | 3 | 7 |
| TE | 5 | 7 | 8 | 5 | 11 | 11 | 3 | 10 | 2 | 18 | 4 | 10 |
| SXT | 15 | 70 | 11 | 4 | 23 | 60 | 17 | 13 | 12 | |||
* Discordances were defined as "major" when A. baumannii was found to be susceptible by one method/system and resistant with the other method/system.
** Discordances were defined as "minor" when A. baumannii was found to be susceptible or resistant by one method/system and intermediate with the other method/system.
*** Imipenem was not included in the table; types of errors in susceptibility testing to imipenem by all systems can be derieved in detail from Table 1.