Zhang Qing, Zhang Wenfang, Li Zheng, Bai Changsen, Li Ding, Zheng Shan, Zhang Peng, Zhang Sihe
Medical Laboratory Department, National Clinical Research Center for Cancer, Key Laboratory of Cancer Prevention and Therapy, Tianjin Medical University Cancer Institute and Hospital, Huan Hu Xi Road, Ti Yuan Bei, He Xi District, Tianjin 300060, P.R. China.
Department of Medical Biochemistry & Cell Biology, School of Medicine, Nankai University, 94 Weijin Road, Nankai District, Tianjin, 300071, PR China.
Diagn Microbiol Infect Dis. 2017 Jul;88(3):247-251. doi: 10.1016/j.diagmicrobio.2017.04.006. Epub 2017 Apr 12.
AmpC β-lactamase-producing Escherichia coli (AmpC-EC) is one of the main antimicrobial resistant pathogens in patients with cancer. A cohort study was performed to evaluate the risk factors, antibiotic therapy, and outcomes of AmpC-EC bacteraemia in hospitalized cancer patients from September 2012 through December 2015. Two hundred forty-eight cases of E. coli bacteraemia were documented in cancer patients, 51 (20.6%) were caused by AmpC-EC and 197 (79.4%) were caused with non-AmpC-EC. Prior exposure to cephalosporins (OR 2.786; 95% CI: 1.094-7.091; P=0.032), carbapenems (OR 2.296; 95% CI: 1.054-5.004; P=0.036), and invasive procedures (OR 4.237; 95% CI: 1.731-10.37; P=0.002) were identified as independent risk factors for AmpC-EC. The time to positivity (TTP) of patients with AmpC-EC bacteraemia tended to be significantly shorter than that of non-AmpC-EC (8.33±2.18h versus 9.48±3.82h; P=0.006), and had a higher 30-day mortality rate in AmpC-EC compared with non-AmpC-EC (25.5% versus 12.2%; P=0.018). Metastasis (OR=2.778, 95% CI: 1.078-7.162; P=0.034), the presence of septic shock (OR=4.983, 95% CI: 1.761-14.10; P=0.002), and organ failure (OR=24.51 95% CI: 9.884-60.81; P<0.001) were independently associated with the overall mortality. The mortality rate showed a gradual increase when appropriate antibiotic therapy (AAT) was delayed more than 48h as determined by the trend test (P<0.001). In conclusion, this study showed that prevalence of AmpC-EC was high in hospitalized cancer patients of our area. Thus, it is necessary to apply appropriate therapeutic approaches and improve outcomes based on the analysis of risk factors for the acquisition of AmpC-EC.
产AmpCβ-内酰胺酶的大肠埃希菌（AmpC-EC）是癌症患者主要的抗菌药物耐药病原体之一。进行了一项队列研究，以评估2012年9月至2015年12月期间住院癌症患者中AmpC-EC菌血症的危险因素、抗生素治疗及预后情况。癌症患者中共记录了248例大肠埃希菌菌血症病例，其中51例（20.6%）由AmpC-EC引起，197例（79.4%）由非AmpC-EC引起。先前使用头孢菌素（比值比[OR]2.786；95%置信区间[CI]：1.094 - 7.091；P = 0.032）、碳青霉烯类药物（OR 2.296；95% CI：1.054 - 5.004；P = 0.036）以及侵入性操作（OR 4.237；95% CI：1.731 - 10.37；P = 0.002）被确定为AmpC-EC的独立危险因素。AmpC-EC菌血症患者的阳性时间（TTP）往往显著短于非AmpC-EC患者（8.33±2.18小时对9.48±3.82小时；P = 0.006），且AmpC-EC患者的30天死亡率高于非AmpC-EC患者（25.5%对12.2%；P = 0.018）。转移（OR = 2.778，95% CI：1.078 - 7.162；P = 0.034）、感染性休克的存在（OR = 4.983，95% CI：1.761 - 14.10；P = 0.002）以及器官衰竭（OR = 24.51，95% CI：9.884 - 60.81；P < 0.001）与总体死亡率独立相关。根据趋势检验，当适当的抗生素治疗（AAT）延迟超过48小时时，死亡率呈逐渐上升趋势（P < 0.001）。总之，本研究表明我们地区住院癌症患者中AmpC-EC的患病率较高。因此，有必要基于对AmpC-EC获得的危险因素分析应用适当的治疗方法并改善预后。
