Role of Persistent Environmental Contamination and Universal Glove and Gown Use in the Acquisition of Extended Spectrum Beta-Lactamase-Producing Enterobacteriaceae in Intensive Care Unit Patients

Abstract

Background: Extended-spectrum beta-lactamase (ESBL)-producing Gram-negative rods (GNR) are emerging pathogens that are associated with considerable morbidity, mortality and costs among hospitalized patients. The association between persistent environmental contamination and acquisition of ESBL-GNR and the effectiveness of universal glove and gown in reducing the transmission of ESBL-GNR among Intensive care unit (ICU) patients has not been well established. Objectives: The objectives of this dissertation are to evaluate the role of persistent environmental contamination using prior room occupant as a proxy in the acquisition of ESBL-GNR and to evaluate the effectiveness of universal glove and gown use in reducing the incidence of ESBL-GNR in ICU patients. Methods: A retrospective cohort study and a quasi-experimental study were conducted using patient data obtained from the central data repository and by laboratory analysis. Peri-anal surveillance cultures were collected from all patients on ICU admission, weekly and at ICU discharge and clinical cultures were collected as medically indicated. Inclusion criteria were ICU length of stay >48 hours and a peri-anal surveillance culture negative for ESBL-GNR on ICU admission. Multivariable logistic regression and segmented linear regression were used to analyze the data. Results: The first study of 18,175 admissions to the University of Maryland Medical Center (UMMC) medical ICU (MICU) and surgical ICU (SICU) between September 1, 2001 and June 30, 2009 showed that prior room occupants' ESBL-Klebsiella and E. coli positive status is not associated with acquiring ESBL- Klebsiella and E. coli after adjusting for potential confounders (Adjusted Odds Ratio (AOR) = 1.39, 95% Confidence Interval (CI) = 0.94 - 2.08). The second study of 6,089 admissions to the MICU between July 1, 2005 and June 30, 2009 showed that universal glove and gown did not reduce acquisition of ESBL-GNR immediately (p =0.48) or long term (p =0.34). Conclusions: Our study results suggest that environmental contamination may not play a significant role in the acquisition of ESBL-GNR at UMMC. Universal glove and gown was not effective at reducing the acquisition of ESBL-GNR immediately and long term at UMMC.