Division of Infectious Diseases, Department of Medicine, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania 19104-6021, USA.
Infect Control Hosp Epidemiol. 2010 Jan;31(1):47-53. doi: 10.1086/649021.
Pseudomonas aeruginosa is one of the most common gram-negative hospital-acquired pathogens. Resistance of this organism to imipenem complicates treatment.
To elucidate the risk factors for imipenem-resistant P. aeruginosa (IRPA) infection or colonization and to identify the effect of resistance on clinical and economic outcomes.
Longitudinal trends in prevalence of IRPA from 2 centers were characterized during the period from 1989 through 2006. For P. aeruginosa isolates obtained during the period from 2001 through 2006, a case-control study was conducted to investigate the association between prior carbapenem use and IRPA infection or colonization, and a cohort study was performed to identify the effect of IRPA infection or colonization on mortality, length of stay after culture, and hospital cost after culture.
From 1989 through 2006, the proportion of P. aeruginosa isolates demonstrating resistance to imipenem increased from 13% to 20% (P < .001, trend). During the period from 2001 through 2006, there were 2,542 unique patients with P. aeruginosa isolates, and 253 (10.0%) had IRPA isolates. Prior carbapenem use was independently associated with IRPA infection or colonization (adjusted odds ratio [OR], 7.92 [95% confidence interval {CI}, 4.78-13.11]). Patients with an IRPA isolate recovered had higher in-hospital mortality than did patients with an imipenem-susceptible P. aeruginosa isolate (17.4% vs 13.4%; P = .01). IRPA infection or colonization was an independent risk factor for mortality among patients with isolates recovered from blood (adjusted OR, 5.43 [95% CI, 1.72-17.10]; P = .004) but not among patients with isolates recovered from other anatomic sites (adjusted OR, 0.78 [95% CI, 0.51-1.21]; P = .27). Isolation of IRPA was associated with longer hospital stay after culture (p < .001) and greater hospital cost after culture (P < .001) than was isolation of an imipenem-susceptible strain. In multivariable analysis, IRPA infection or colonization remained an independent risk factor for both longer hospital stay after culture (coefficient, 0.20 [95% CI, 0.04-0.36]; P = .02) and greater hospital cost after culture (coefficient, 0.30 [95% CI, 0.06-0.54]; P = .02).
The prevalence of IRPA infection or colonization has increased significantly, with important implications for both clinical and economic outcomes. Interventions to curb this continued increase and strategies to optimize therapy are urgently needed.
铜绿假单胞菌是最常见的革兰氏阴性医院获得性病原体之一。该菌对亚胺培南的耐药性使治疗复杂化。
阐明耐亚胺培南铜绿假单胞菌（IRPA）感染或定植的危险因素，并确定耐药性对临床和经济结局的影响。
在 1989 年至 2006 年期间，对来自 2 个中心的 IRPA 的纵向流行趋势进行了描述。对于 2001 年至 2006 年期间获得的铜绿假单胞菌分离株，进行了病例对照研究，以调查先前使用碳青霉烯类药物与 IRPA 感染或定植之间的关系，并进行了队列研究，以确定 IRPA 感染或定植对死亡率、培养后住院时间和培养后住院费用的影响。
从 1989 年到 2006 年，对亚胺培南耐药的铜绿假单胞菌分离株的比例从 13%增加到 20%（P <.001，趋势）。在 2001 年至 2006 年期间，共有 2542 例独特的铜绿假单胞菌分离株患者，其中 253 例（10.0%）为 IRPA 分离株。先前使用碳青霉烯类药物与 IRPA 感染或定植独立相关（调整优势比[OR]，7.92 [95%置信区间{CI}，4.78-13.11]）。携带 IRPA 分离株的患者比携带亚胺培南敏感的铜绿假单胞菌分离株的患者住院死亡率更高（17.4%比 13.4%；P =.01）。IRPA 感染或定植是血液分离株患者死亡率的独立危险因素（调整 OR，5.43 [95% CI，1.72-17.10]；P =.004），但不是其他解剖部位分离株患者死亡率的独立危险因素（调整 OR，0.78 [95% CI，0.51-1.21]；P =.27）。与分离出对亚胺培南敏感的菌株相比，分离出 IRPA 与培养后住院时间延长（p <.001）和培养后住院费用增加（p <.001）有关。在多变量分析中，IRPA 感染或定植仍然是培养后住院时间延长（系数，0.20 [95% CI，0.04-0.36]；P =.02）和培养后住院费用增加（系数，0.30 [95% CI，0.06-0.54]；P =.02）的独立危险因素。
耐亚胺培南铜绿假单胞菌的感染或定植率显著上升，对临床和经济结局均有重要影响。迫切需要采取措施遏制这一持续增长，并优化治疗策略。
