Prevalence of Carbapenem-Resistant Enterobacteriaceae (CRE) at a Tertiary-Care Center in the United States

Abstract

Background: Quantification of the magnitude of CRE both within a facility and regionally poses a challenge to healthcare institutions. Periodic point-prevalence surveys are recommended by the CDC CRE tool kit as a facility-level prevention strategy. A 2016 point-prevalence survey of 2 high-risk units at a tertiary-care center in the United States for CRE colonization found that all patients surveyed were negative for CRE. The infection prevention (IP) team repeated the study in 2019 to reassess the prevalence of CRE in the healthcare facility. Methods: A point-prevalence survey was performed in November 2019 on the same 2 high-risk units surveyed in 2016. A perirectal flocked swab was collected from all patients unless a patient refused and/or a contraindication to rectal swab was present. Swabs were inoculated onto HardyChrom TM CRE agar for incubation in ambient air at 35°C for 24 hours. Organism identification was performed using MALDI-TOF mass spectrometry on a MBT Smart by Bruker. Results: None of the patients on either high-risk unit was known to be colonized or infected with CRE at the time of the point-prevalence survey. Of 41 perirectal swabs collected, 4 (9.8%) were positive for CRE. None (0 of 20) were surgical ICU patients and 4 of 21 (19%) were medical ICU patients. All positive swabs revealed different organisms identified as follows: Escherichia coli, Enterobacter cloacae, Enterobacter kobai, and Enterobacter aerogenes. All 4 positive patients had had recent contact with multiple acute-care hospitals. Also, 2 had been transferred for liver transplant evaluation. None of these patients had received a carbapenem during their admission to the facility. Conclusion: CRE are increasingly identified in healthcare centers in the United States. Centers previously classified as low prevalence will need to maintain preventive strategies to limit transmission risks as colonized patients arrive in the facility for care. Adoption of a robust horizontal infection prevention program may be an effective strategy to avoid the spread of CRE.

Funding: None

Disclosures: Michelle Doll reports a research grant from Molnlycke Healthcare.