Risk of Acquiring Extended-Spectrum Beta-Lactamase-Producing Klebsiella Species and Escherichia coli from Prior Room Occupants in the Intensive Care Unit
Ajao AO, Johnson K, Harris AD, et al
Infect Control Hosp Epidemiol. 2013;34:453-458
The Contaminated Patient Room
An increasing body of literature suggests that environmental contamination with multidrug-resistant organisms (MDROs) in healthcare institutions is frequent and widespread. From that standpoint, proximity or exposure to a patient or the environment of a patient known to be colonized or infected with an MDRO would be expected to increase the risk that a susceptible host would acquire that pathogen.
A great deal of attention is being paid to developing ways of enhancing and improving environmental decontamination to mitigate the risk for nosocomial transmission. As a result of the complexity of transmission dynamics, uncertainty about the mechanism of carriage, and the frequency and extent of shedding, this is not an easy problem to solve.
Study Summary
Ajao and colleagues contributed to the existing data in this field by conducting a retrospective cohort study of patients admitted to medical and surgical intensive care units (ICUs) at an academic medical center between September 2001 and June 2009. They were able to measure colonization rates accurately because perianal surveillance cultures were collected on all patients (about 90%) at ICU admission, weekly, and at discharge.
The main outcome was extended-spectrum beta-lactamase (ESBL) acquisition, defined as negative culture results for ESBL on admission and positive cultures at discharge. A major strength of this study was the ability to obtain pulsed-field gel electrophoresis on ESBL-positive isolates from previous occupants of the room and from patients who acquired the pathogen during their ICU stay.