Department of Microbiology, Kelvin Laboratories, Royal Victoria Hospital, Belfast Trust, Grosvenor Road, BT126BA Belfast, UK.
J Antimicrob Chemother. 2011 Sep;66(9):2152-8. doi: 10.1093/jac/dkr264. Epub 2011 Jun 23.
A Trust strategy to reduce ciprofloxacin use was implemented at a University hospital. This study aimed to investigate whether the susceptibility of Gram-negative organisms (GNO) to alternative antimicrobials (co-amoxiclav, doxycycline, aztreonam, piperacillin/tazobactam, meropenem and gentamicin) changed, and whether there was any relationship between GNO susceptibility to these antimicrobials and ciprofloxacin usage.
The first isolate of each GNO from blood cultures, sputum and urine of hospitalized adults, between January 2008 and August 2009, was included. Antibiotic usage and GNO susceptibility were investigated using linear regression. The association between defined daily dose/1000 occupied bed days (DDD/1000 OBD) and susceptibility was assessed using Pearson correlation and linear regression.
Ciprofloxacin use decreased significantly by 4.37 DDD/1000 OBD per month [95% confidence interval (CI) 2.99, 5.75; P < 0.001], while aztreonam and gentamicin use increased significantly (aztreonam: 0.22 DDD/1000 OBD increase per month; 95% CI 0.10, 0.34; P = 0.001; gentamicin: 0.46 DDD/1000 OBD increase per month; 95% CI 0.12, 0.79; P = 0.01). There was no change in meropenem, co-amoxiclav, doxycycline or piperacillin/tazobactam use. When DDD/1000 OBD for all non-quinolone antimicrobials were pooled, use increased significantly by 3.33 DDD/1000 OBD per month (95% CI 0.79, 5.87; P = 0.013). There were 5410 GNO isolates. A significant increase was recorded in the proportion of GNO susceptible to ciprofloxacin (0.55% increase in susceptibility per month; 95% CI 0.38, 0.72; P < 0.001), aztreonam (1.87% susceptibility increase per month; 95% CI 1.18, 2.55; P < 0.001), piperacillin/tazobactam (0.18% susceptibility increase per month; 95% CI 0.03, 0.33; P = 0.021), meropenem (0.27% susceptibility increase per month; 95% CI 0.08, 0.47; P = 0.009) and gentamicin (0.17% susceptibility increase per month; 95% CI 0.04, 0.29; P = 0.011). An inverse association between ciprofloxacin use and susceptibility to ciprofloxacin (P < 0.001), piperacillin/tazobactam (P = 0.12), aztreonam (P= 0.002), meropenem (P = 0.015) and gentamicin (P = 0.034) is suggested.
These data demonstrate reduced ciprofloxacin usage and concomitant increasing GNO susceptibility to β-lactams. While definitive evidence of a causal relationship is beyond the capability of a single-centre study, the results suggest that reducing quinolone exposure may exert a favourable effect on the quinolone, β-lactam and gentamicin susceptibility of GNO.
一家大学医院实施了一项环丙沙星使用的信托策略。本研究旨在调查革兰氏阴性菌（GNO）对替代抗菌药物（复方新诺明、强力霉素、氨曲南、哌拉西林/他唑巴坦、美罗培南和庆大霉素）的敏感性是否发生变化，以及这些抗菌药物对 GNO 的敏感性与环丙沙星使用之间是否存在任何关系。
纳入 2008 年 1 月至 2009 年 8 月期间住院成人血培养、痰和尿的每一种 GNO 的首次分离株。使用线性回归调查抗生素使用和 GNO 敏感性。使用 Pearson 相关系数和线性回归评估每个定义日剂量/1000 占用床日（DDD/1000 OBD）与敏感性之间的关系。
环丙沙星的使用量每月显著减少 4.37 DDD/1000 OBD[95%置信区间（CI）2.99，5.75；P<0.001]，而氨曲南和庆大霉素的使用量则显著增加（氨曲南：每月增加 0.22 DDD/1000 OBD；95%CI 0.10，0.34；P=0.001；庆大霉素：每月增加 0.46 DDD/1000 OBD；95%CI 0.12，0.79；P=0.01）。美罗培南、复方新诺明、强力霉素或哌拉西林/他唑巴坦的使用量没有变化。当所有非喹诺酮类抗菌药物的 DDD/1000 OBD 汇总时，每月使用量显著增加 3.33 DDD/1000 OBD（95%CI 0.79，5.87；P=0.013）。共分离出 5410 株 GNO。GNO 对环丙沙星的敏感性显著增加（每月增加 0.55%的敏感性；95%CI 0.38，0.72；P<0.001）、氨曲南（每月增加 1.87%的敏感性；95%CI 1.18，2.55；P<0.001）、哌拉西林/他唑巴坦（每月增加 0.18%的敏感性；95%CI 0.03，0.33；P=0.021）、美罗培南（每月增加 0.27%的敏感性；95%CI 0.08，0.47；P=0.009）和庆大霉素（每月增加 0.17%的敏感性；95%CI 0.04，0.29；P=0.011）。环丙沙星的使用与环丙沙星（P<0.001）、哌拉西林/他唑巴坦（P=0.12）、氨曲南（P=0.002）、美罗培南（P=0.015）和庆大霉素（P=0.034）的敏感性之间存在显著的负相关关系。
这些数据表明环丙沙星的使用减少，同时革兰氏阴性菌对β-内酰胺类药物的敏感性增加。虽然单一中心研究的能力无法确定因果关系的明确证据，但结果表明，减少喹诺酮类药物的暴露可能对革兰氏阴性菌的喹诺酮类、β-内酰胺类和庆大霉素的敏感性产生有利影响。
