Table 1.
Double Disc Synergy Test (DDST) for confirmation of ESBL-producing E. coli.
| Clear Zone Inhibition 1 | Diameter (mm) 2 | |||
|---|---|---|---|---|
| 1557 | 1584 | 1587 | 1591 | |
| CTX | 13 | 11 | 12 | 12 |
| CTX/CA | 23 | 19 | 20 | 18 |
| CAZ | 18 | 12 | 12 | 8 |
| CAZ/CA | 25 | 18 | 24 | 15 |
1 Antimicrobial agents are abbreviated as follows: Cefotaxime (CTX), Cefotaxime plus Clavulanic acid (CTX/CA), Ceftazidime (CAZ), Ceftazidime plus Clavulanic acid (CTX/CA). 2 The test was considered to be positive when the zone of inhibition of cefotaxime plus clavulanic acid or ceftazidime plus clavulanic acid was >5 mm compared to their respective single discs.