Cranendonk Duncan R, van der Valk Marc, Langenberg M L, van der Meer Jan T M
Department of Infectious Diseases, Academic Medical Center, Amsterdam, The Netherlands.
Scand J Infect Dis. 2012 May;44(5):363-8. doi: 10.3109/00365548.2011.641506. Epub 2011 Dec 27.
Escherichia coli is a common cause of bacteraemia and is increasingly resistant to ciprofloxacin and gentamicin. The primary objective of this study was to investigate how often this leads to inadequate initial antimicrobial treatment. Secondary goals were to determine factors associated with inadequate empirical therapy and to assess its impact on mortality and length of stay.
All patients with an E. coli bacteraemia hospitalized in 2008 were identified retrospectively. Initial antimicrobial therapy and clinical outcomes of all patients with an isolate resistant to gentamicin and/or ciprofloxacin (cases) were compared to those of a group of randomly selected patients in whom a gentamicin and ciprofloxacin susceptible E. coli was isolated (controls).
One hundred and thirty-six unique patients had E. coli bacteraemia. Of these, 34 patients were identified as cases and were compared to 34 controls. Among the cases, 97% of the E. coli was resistant to ciprofloxacin and 44% to gentamicin. Resistance to amoxicillin was high in both cases (94%) and controls (65%). In 41% of the cases initial antimicrobial therapy was inadequate, compared to only 3% in the controls. The majority of inadequately treated cases had a biliary focus (64%). Infections in cases were more often healthcare-associated than infections in controls (62% vs 26%). E. coli with the same resistance pattern had been isolated before in adequately treated cases more often than in inadequately treated cases. Mortality did not differ significantly between cases and controls.
Neither ciprofloxacin nor amoxicillin should be used as empirical therapy in patients with a presumed E. coli bacteraemia.
大肠杆菌是菌血症的常见病因，且对环丙沙星和庆大霉素的耐药性日益增强。本研究的主要目的是调查这种情况导致初始抗菌治疗不充分的频率。次要目标是确定与经验性治疗不充分相关的因素，并评估其对死亡率和住院时间的影响。
回顾性确定2008年住院的所有大肠杆菌菌血症患者。将所有分离出对庆大霉素和/或环丙沙星耐药的菌株的患者（病例组）的初始抗菌治疗和临床结局，与一组随机选择的分离出对庆大霉素和环丙沙星敏感的大肠杆菌的患者（对照组）进行比较。
136例独特患者患有大肠杆菌菌血症。其中，34例患者被确定为病例组，并与34例对照组进行比较。在病例组中，97%的大肠杆菌对环丙沙星耐药，44%对庆大霉素耐药。病例组（94%）和对照组（65%）对阿莫西林的耐药率都很高。41%的病例组初始抗菌治疗不充分，而对照组仅为3%。大多数治疗不充分的病例有胆道感染源（64%）。病例组的感染比对照组更常与医疗保健相关（62%对26%）。在充分治疗的病例中，之前分离出具有相同耐药模式的大肠杆菌的情况比治疗不充分的病例更常见。病例组和对照组的死亡率没有显著差异。
对于疑似大肠杆菌菌血症的患者，不应将环丙沙星或阿莫西林用作经验性治疗药物。
