534. Active Screening for Carbapenemase Producing Enterobacteriaceae: Yield and Cost Considerations

Abstract

Background

During 2016, our hospital experienced an outbreak with carbapenemase-producing Enterobacteriaceae (CPE) in our solid-organ transplant (SOT) population. Since this outbreak and until now, our hospital has implemented active CPE screening of patients admitted to SOT units and point prevalence surveillances in any unit with a known CPE patient. The present study evaluates the yield of these screening tests and their cost since implementation.

Methods

This retrospective cohort was performed in a 600-bed hospital in Milwaukee, WI. CPE screening tests were retrieved from the clinical microbiology laboratory dataset from January 2016 to April 2019. CPE tests are performed on rectal swabs or stool samples using the CDC broth enrichment method followed by MIC confirmation using Etest. CPE patients were placed on enhanced precautions (gowns, gloves, booties) and were cohorted geographically and to 1:1 nursing and nurse aid staff.

Results

A total of 6,684 samples belonging to 3,383 patients were processed (1.9 samples/patient). Two hundred thirty (3.44%) had carbapenem-resistant Enterobacteriaceae, although only 33 isolates (0.49%) were confirmed as either KPC (n = 31) or NDM (n = 2) positive. Out of the 3,383 patients tested, 121 were identified as carriers of carbapenem-resistant isolates but only 11 (0.32%) were CPE (KPC = 11; NDM = 2). The incidence of new CPE patients during 2016 was 0.82% but decreased to 0.28% and 0.33% in 2017 and 2018, respectively. The units with the highest number of CPE patients were the transplant intensive care unit (n = 6) and the step-down SOT unit (n = 3). Negative cultures were quoted at $8.49 per sample but culture plates with colonies increased the cost per test to $28.44. The total cost for all the 6,684 screening tests was calculated at $61,335. The cost of CPE screening per positive CPE patient identified comes up to $5,575 (not including RN collection time).

Conclusion

In an institution with staff and CPE patient cohorting, active screening of CPE positive patients was relatively expensive given our low -level of transmission. In the near future, we plan to stop staff and patient cohorting due to the high stress that these interventions place on our hospital staff. This might ensue in increase transmission, which will be detected by CPE screening tests.

Disclosures

All authors: No reported disclosures.