Original Article

Risk Factors for the Acquisition of Nosocomial Infection with Carbapenem-Resistant Klebsiella pneumoniae

Authors: Dandan Wu, MD, Jiachang Cai, PhD, Jin Liu, MD


Objectives: Carbapenem-resistant Klebsiella pneumoniae (CRKP) has been increasingly reported all over the world. In this study, we aimed to investigate the risk factors for the acquisition of nosocomial CRKP infections.

Methods: We conducted a case-control study with data collected from thirty-nine patients with nosocomially acquired CRKP infection between July 2006 and July 2008. Controls were selected at a ratio of 1:2 from patients with nosocomial carbapenem-susceptible Klebsiella pneumoniae (CSKP) infection and were matched with CRKP cases for site of infection and the date of hospital admission (± within 5 days). T test, chi-square test, and logistic regression were used for statistical analysis.

Results: Bivariable analysis showed that the age of the patients (P = 0.038), days of hospital stay prior to isolation of Klebsiella pneumoniae (K. pneumoniae) (P = 0.043), altered consciousness (P = 0.007), intensive care unit (ICU) admission within two weeks (P = 0.003), tracheal intubation (P = 0.027), mechanical ventilation (P = 0.009), number of changes in antibiotics ≥4 (P = 0.001), exposure to carbapenems (P = 0.002), exposure to fourth-generation cephalosporins (P = 0.027), and exposure to piperacillin-tazobactams/cefoperazone-sulbactams (P = 0.043) and glycopeptides (P = 0.042) were related to CRKP infection. The multivariable analysis showed that ICU admission (within two weeks) [odds ratio (OR):4.68, 95% confidence intervals (CI):1.15–19.09, P = 0.031], exposure to carbapenems (OR: 12.69, 95% CI: 2.09–77.10, P = 0.006) and exposure to glycopeptides (OR: 3.57, 95% CI: 1.11–11.42, P = 0.032) were independent risk factors for nosocomial CRKP infections.

Conclusion: Several factors are related to CRKP infections. ICU admission (within two weeks) or prior exposure to carbapenems or glycopeptides are independent risk factors for the acquisition of nosocomial CRKP infections.

Key Points

* The emergence of carbapenem-resistant Klebsiella pneumoniae (CRKP) has been increasingly reported with the widespread use of carbapenems.

* This study found that intensive care unit (ICU) admission within two weeks, or prior exposure to carbapenems or glycopeptides were independent risk factors for the acquisition of nosocomial CRKP infections.

* The practice of aseptic invasive procedures, use of universal precautions, and reasonable and judicious antibiotic utilization (especially carbapenems) are critical for the control of CRKP emergence and spread.

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