Table 5. Changes in resistance patterns of new extended-spectrum β-lactamase isolates during the preintervention period, Northern Ireland, UK*.
| Antibiotic comparison |
AAH, no. resistant isolates/total tested (%) | CH, no. resistant isolates/total tested (%) | |||||
|---|---|---|---|---|---|---|---|
| Preintervention resistance |
Intervention resistance |
p value |
|
Preintervention resistance |
Intervention resistance |
p value |
|
| Preintervention vs. intervention | |||||||
| Amoxicillin/clavulanic acid | 59/65 (90.8) | 76/129 (58.9) | <0.01 | 38/41 (92.7) | 33/42 (78.6) | 0.07 | |
| Piperacillin/tazobactam | 50/65 (76.9) | 29/131 (22.1) | <0.01 | 28/41 (68.3) | 21/41 (51.2) | 0.11 | |
| Ciprofloxacin | 43/66 (65.2) | 78/132 (59.1) | 0.41 | 25/40 (62.5) | 26/40 (65.0) | 0.82 | |
| Gentamicin |
20/67 (29.9) |
38/135 (28.1) |
0.81 |
|
15/41 (36.6) |
22/42 (52.4) |
0.15 |
| Intervention vs. postintervention | |||||||
| Amoxicillin/clavulanic acid | 76/129 (58.9) | 80/122 (65.6) | 0.28 | NR | NR | NR | |
| Piperacillin/tazobactam | 29/131 (22.1) | 41/121 (33.9) | 0.04 | NR | NR | NR | |
| Ciprofloxacin | 78/132 (59.1) | 92/122 (75.4) | <0.01 | NR | NR | NR | |
| Gentamicin | 38/135 (28.1) | 63/122 (51.6) | <0.01 | NR | NR | NR | |
*In AAH (antibiotic cycling policy) and CH (standard antibiotic policy), the reintervention period was November 2011–September 2013, and the intervention period was October 2013–September 2015. In AAH, the postintervention period was October 2015–September 2016. Bold indicates statistical significance. AAH, Antrim Area Hospital; CH, Causeway Hospital; NR, data not recorded.