Universal MRSA Decolonization in ICU Leads to Fewer Bloodstream Infections
Clinical question
Does universal decolonization for methicillin-resistant Staphylococcus aureus (MRSA) in patients in the intensive care unit decrease the rate of MRSA-positive clinical cultures?
Bottom line
As compared with no decolonization or a targeted decolonization, a universal decolonization strategy for MRSA using intranasal mupirocin and chlorhexidine bathing cloths for all patients admitted to the intensive care unit (ICU) is most effective at decreasing MRSA-positive clinical cultures and ICU-acquired bloodstream infections. Overall, you would need to treat 54 patients with universal decolonization to prevent one bloodstream infection. The cost effectiveness of this strategy as well as the concern of emerging resistance was not addressed in this study. (LOE = 1b-)
Reference
Study design
Randomized controlled trial (nonblinded)
Funding source
Government
Allocation
Uncertain
Setting
Inpatient (ICU only)
Synopsis
Prior research has shown that daily bathing with chlorhexidine lowers the rate of MRSA acquisition and decreases the overall number of hospital-acquired bloodstream infections in the ICU (Daily POEM 4/26/13). The current study’s goal was to identify whether targeted or universal MRSA decolonization is the most effective at reducing MRSA infections in the ICU. Investigators randomized 43 hospitals to use 1 of 3 strategies within all their adult ICUs: (1) MRSA screening and contact isolation only; (2) screening, isolation, and decolonization of MRSA carriers; (3) decolonization of all patients without any screening procedures. Screening for MRSA was performed via swabs of bilateral nares upon ICU admission in the first 2 groups. Contact precautions were implemented for those with a positive MRSA screening result in groups 1 and 2 and for those with history of MRSA colonization or infection in all groups. Decolonization in groups 2 and 3 consisted of 5 days of twice-daily intranasal mupirocin, as well as daily bathing with chlorhexidine cloths during the entire ICU stay. Baseline characteristics of the patient populations in each group were similar. Patients in all adult ICUs of a participating hospital were assigned to the same study group. Although both universal and targeted decolonization resulted in a significant reduction in the primary outcome of MRSA-positive clinical cultures, the universal strategy was found to be most effective (hazard ratio [HR] = 0.63 for the universal strategy; HR = 0.75 for the targeted strategy; and HR = 0.92 for screening and isolation; P = .01). Additionally, universal decolonization led to the greatest reduction of overall bloodstream infections (HR = 0.56 for universal; HR = 0.78 for targeted; HR = 0.99 for screening and isolation; P < .001). Of note, the universal decolonization group contained 3 of the 4 hospitals that performed bone marrow and solid-organ transplantations, resulting in a higher baseline risk of infection than the other groups, but this difference was not statistically significant. Overall, only severe adverse events were noted in this study and all were classified as mild pruritus or rash due to chlorhexidine bathing. Investigators did not evaluate the cost-effectiveness of the different strategies nor did they examine the emergence of resistance with widespread use of chlorhexidine and mupirocin.
Dr. Kulkarni is an assistant professor of hospital medicine at Northwestern University in Chicago.