Lee Yi-Tzu, Chiang Mei-Chun, Kuo Shu-Chen, Wang Yung-Chih, Lee I-Hsin, Chen Te-Li, Yang Ya-Sung
Faculty of Medicine, School of Medicine, National Yang-Ming University, Taipei, Taiwan.
Department of Emergency Medicine, Taipei Veterans General Hospital, Taipei, Taiwan.
PLoS One. 2016 Sep 19;11(9):e0163271. doi: 10.1371/journal.pone.0163271. eCollection 2016.
The carbapenem breakpoints set by different organizations for Acinetobacter are discordant, but supporting clinical data are lacking. This study aimed to provide the first clinical outcome data to support the carbapenem breakpoints for Acinetobacter baumannii (Ab) group in patients with bacteremia. This study included 117 adults who received carbapenems for treatment of Ab group bacteremia in Taipei Veterans General Hospital over an 8-year period. We analyzed 30-day mortality rates among patient groups acquiring isolates with different carbapenem minimal inhibitory concentrations (MICs). The carbapenem MIC breakpoint derived from classification and regression tree (CART) analysis to delineate the risk of 30-day mortality was between MICs of ≤ 4 mg/L and ≥ 8 mg/L. Mortality rate was higher in patients acquiring isolates with carbapenem MIC ≥ 8 mg/L than ≤ 4 mg/L, by bivariate (54.9% [28/51] vs 25.8% [17/66]; P = 0.003) and survival analysis (P = 0.001 by log-rank test). Multivariate analysis using logistic regression and Cox regression models including severity of illness indices demonstrated that treating patients with Ab group bacteremia caused by isolates with a carbapenem MIC ≥ 8 mg/L with carbapenem was an independent predictor of 30-day mortality (odds ratio, 5.125; 95% confidence interval [CI], 1.946-13.498; P = 0.001, and hazard ratio, 2.630; 95% CI, 1.431-4.834; P = 0.002, respectively). The clinical outcome data confirmed that isolates with MIC ≤ 4 mg/L were susceptible to carbapenem, and those with MIC ≥ 8 mg/L were resistant in patients with Ab group bacteremia.
不同组织针对不动杆菌设定的碳青霉烯类药物断点不一致，但缺乏支持性临床数据。本研究旨在提供首个临床结局数据，以支持用于菌血症患者鲍曼不动杆菌（Ab）组的碳青霉烯类药物断点。本研究纳入了在8年期间于台北荣民总医院接受碳青霉烯类药物治疗Ab组菌血症的117名成年人。我们分析了获得不同碳青霉烯类药物最低抑菌浓度（MIC）分离株的患者组的30天死亡率。通过分类回归树（CART）分析得出的用于描述30天死亡风险的碳青霉烯类药物MIC断点在≤4 mg/L和≥8 mg/L的MIC之间。获得碳青霉烯类药物MIC≥8 mg/L分离株的患者死亡率高于MIC≤4 mg/L的患者，经双变量分析（54.9% [28/51] 对25.8% [17/66]；P = 0.003）和生存分析（对数秩检验P = 0.001）。使用包括疾病严重程度指数的逻辑回归和Cox回归模型进行的多变量分析表明，用碳青霉烯类药物治疗由碳青霉烯类药物MIC≥8 mg/L分离株引起的Ab组菌血症患者是30天死亡率的独立预测因素（比值比，5.125；95%置信区间[CI]，1.946 - 13.498；P = 0.001，危险比，2.630；95% CI，1.431 - 4.834；P = 0.002）。临床结局数据证实，在Ab组菌血症患者中，MIC≤4 mg/L的分离株对碳青霉烯类药物敏感，而MIC≥8 mg/L的分离株耐药。
