When Should Contact Precautions and Active Surveillance Be Used to Manage Patients with Multidrug-Resistant Enterobacteriaceae?

Abstract

Affiliations: 1. Department of Microbiology and Infection Prevention and Control, Auckland City Hospital, Auckland, New Zealand; 2. Duke Infection Control Outreach Network, Division of Infectious Diseases, Duke University Medical Center, Durham, North Carolina. Received November 28, 2011; accepted February 23, 2012; electronically published May 9, 2012. 2012 by The Society for Healthcare Epidemiology of America. All rights reserved. 0899-823X/2012/3307-0016$15.00. DOI: 10.1086/666333 Approximately 30% of all healthcare-associated infections (HAIs) are caused by Enterobacteriaceae. This percentage may be even higher among critically ill patients, in whom Enterobacteriaceae may cause up to 70% of HAIs. It is concerning, therefore, that the prevalence of acquired b-lactamases is rapidly increasing among common Enterobacteriaceae species. In addition, the genes encoding these enzymes move readily between strains and species, resulting in the emergence of new multidrug-resistant Enterobacteriaceae (MRE) on a virtually continuous basis. This situation poses a difficult challenge for infection control practitioners that is frequently addressed by using contact precautions (CP). CP involves management of infected patients in a single room and the use of dedicated equipment, gowns, and gloves for all patient contact. In conjunction with this practice, active surveillance (AS) is often used. AS involves screening asymptomatic patients for colonization with MRE (usually followed by implementation of CP). Most of the evidence supporting the use of CP and AS comes from studies of methicillin-resistant Staphylococcus aureus (MRSA), yet even for MRSA these practices remain contentious. For MRE, the evidence is less conclusive. For example, reports describing temporal associations between the resolution of MRE outbreaks and the initiation of CP and AS are frequently confounded by the simultaneous introduction of additional infection control measures. Similarly, descriptive reports of outcomes with CP and AS in nonoutbreak settings are limited by a lack of control groups for comparison. In addition, the use of CP has been associated with adverse patient outcomes, such as depression and reduced contact with attending physicians. Finally, even when the benefits of CP and AS outweigh the risks, their use may not be costeffective, particularly in settings where MRE are endemic. From a practical standpoint, the limited evidence currently available means that the decision to use CP and AS should be based on knowledge of local epidemiology. In the following discussion, we propose some principles to consider (Table 1) and highlight several areas requiring further research regarding the use of CP and AS to control MRE.