By Stan Deresinski, MD, FACP, FIDSA

Clinical Professor of Medicine, Stanford University

Dr. Deresinski reports no financial relationships relevant to this field of study.

SYNOPSIS: The value of routine contact precautions for VRE and MRSA is strongly challenged.

SOURCES: Martin EM, Russell D, Rubin Z, et al. Elimination of routine contact precautions for endemic methicillin-resistant Staphylococcus aureus and vancomycin-resistant enterococcus: A retrospective quasi-experimental study. Infect Control Hosp Epidemiol 2016;37:1323-1330.

Lemieux C, Gardam M, Evans G, et al. Longitudinal multicenter analysis of outcomes after cessation of control measures for vancomycin-resistant enterococci. Infect Control Hosp Epidemiol 2016:1-7. [Epub ahead of print] PubMed PMID: 27804901.

Making hospital infectious disease rounds has become a continual ballet of donning-doffing-donning gowns and gloves because of the enormous number of patients placed in contact isolation at many hospitals. The most frequent reasons for such precautions are patient infection and/or colonization with methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant enterococcus (VRE), Clostridium difficile, and multidrug-resistant Gram-negative bacilli. It has been pointed out recently, however, that high-quality evidence justifying the use of contact precautions for MRSA and VRE is lacking.

Martin and colleagues at the UCLA Medical Center and Santa Monica Hospital analyzed changes in the epidemiology of MRSA and VRE after their discontinuation of routine contact precautions for patients with these organisms as of July 1, 2014. At UCLA, all rooms were single-patient, while at the Santa Monica Hospital, most were. Prior to that date, all patients with active infection, a history of active infection, or of current or past positive surveillance cultures were placed under contact precautions consisting of the use of gowns and gloves in addition to standard precautions. After that date, contact isolation was required only if the patient had a draining wound. Another policy change, which likely acted as a confounder in interpreting the change in isolation policy, had been made in May 2004. Prior to that time, only intensive care patients received daily chlorhexidine bathing, while thereafter this intervention was applied throughout both hospitals.

Analysis of the first year after discontinuation of routine contact precautions for MRSA and VRE found no evidence of increased rates of recovery of these organisms. Thus, the average positive culture rates of MRSA changed from 0.40 to 0.32 cultures/100 admissions (P = 0.09), while those of VRE changed from 0.48 to 0.40 cultures/100 admissions. Prior to the change, 28.5% of intensive care beds and 19% of medicine surgery beds were on contact isolation. The investigators estimated overall cost savings of $643,776 per year — savings of $729,572 resulting from reduced use of gowns for staff minus $85,796 per year for hospital-wide chlorhexidine bathing. Additional cost savings ($4.6 million) were calculated from an estimate that the total nursing time spent in donning gowns and gloves over one year exceeded 45,000 hours — although it was accepted that the actual dollar cost savings could not be realized but that the extra time would allow for greater focus on direct patient care.

Lemieux and colleagues reported outcomes after all VRE screening and isolation practices at four large academic hospitals in Ontario, Canada, were discontinued on July 1, 2012. Prior to that time, VRE surveillance of stool or rectal swabs was performed. Relative outcomes were expressed as the incidence rate ratio (IRR), with values < 1 indicating a decreased risk of a given outcome. Analysis found that the IRR for VRE infection (not simply colonization) was 0.59, while it was 0.54 for VRE bacteremia, and 0.54 for all-cause mortality — none of these values suggestive of improved outcomes were statistically significant. Thus, the authors concluded that cessation of VRE control measures had no significant negative effect. There appeared to be an increase in numbers of patients with hematological malignancy with VRE infection. This may have accounted, at least in part, for a significant increase in use of daptomycin (but not linezolid) — which, at least in the United States, is a potential cause of financial toxicity.

Although Lemieux et al observed an apparent increase in VRE infections in patients with hematologic malignancies, this result conflicts with that of Almyrouds et al.1 That group of investigators, in examining two consecutive three-year periods, found no evidence of an increase in VRE bacteremia in such patients or in those who had undergone hematopoietic stem cell transplantation after discontinuation of active surveillance and contact precautions for VRE colonization.

COMMENTARY

It has been recommended widely that patients historically or currently colonized or infected with VRE or MRSA be maintained in isolation with use of contact precautions to reduce transmission of these organisms. However, patient isolation is not without its unfavorable consequences. Although not confirmed in all studies, these consequences have included fewer and shorter healthcare provider contact, increased medication errors, increased risk of pressure ulcers and falls, and, importantly, adverse psychological effects. Increased cost also has been added to the list. Thus, Tran and colleagues, in a multicenter, retrospective propensity score-matched cohort study found that respiratory isolation was associated with a prolonged length of stay and of cost.2 These also were true for patients with MRSA placed in isolation with contact precautions, but this group also had a greater 30-day readmission rate. The results reviewed here were confirmed by at least two studies presented at IDWeek (see abstracts 275 and 277 available at https://idsa.confex.com/idsa/2016/webprogram/Session8193.html).

Overall, a reasonably firm conclusion can be reached that routine contact isolation for endemic MRSA and VRE is unnecessary (and may be harmful) when there is active maintenance of hand hygiene, environmental cleaning, and chlorhexidine bathing.

REFERENCES

  1. Almyroudis NG, Osawa R, Samonis G, et al. Discontinuation of systematic surveillance and contact precautions for vancomycin-resistant enterococcus (VRE) and its impact on the incidence of VRE faecium bacteremia in patients with hematologic malignancies. Infect Control Hosp Epidemiol 2016;37:398-403.
  2. Tran K, Bell C, Stall N, et al. The effect of hospital isolation precautions on patient outcomes and cost of care: A multi-site, retrospective, propensity score-matched cohort study. J Gen Intern Med 2016 Oct 17. [Epub ahead of print] PubMed PMID: 27752880.