A predictive score for the result of carbapenem-resistant Enterobacterales and vancomycin-resistant enterococci screening

Abstract

Background: The duration of extensively drug-resistant bacteria (XDR) carriage depends on several factors for which the information can be difficult to recover.

Aim: To determine whether past screening and clinical results of patients can predict the results of subsequent screening.

Methods: In total, 256 patients were retrospectively included from 10 healthcare centres in France from January 2014 to January 2022. We created a predictive clearance score, ranging from -5 to +7, that included the number of XDR species and the type of resistance detected in the sample, as well as the time from the last positive sample, the number of previous consecutive negative samples, and obtaining at least one negative PCR result in the collection. This score could be used for the upcoming rectal screening of a patient carrying an XDR as soon as the last screening sample was negative.

Findings: The negative predictive value was >99% for score ≤0. The median time to achieve XDR clearance was significantly shorter for a score of 0 (443 days (259-705)) than that based on previously published criteria.

Conclusion: This predictive score shows high performance for the assessment of XDR clearance. Relative to previous guidelines, it could help to lift specific infection prevention and control measures earlier. Nevertheless, the decision should be made according to other factors, such as antimicrobial use and adherence to hand hygiene.

Keywords: Carbapenem-resistant Enterobacterales; Carriage; Extensively drug-resistant bacteria; Predictive score of clearance; Screening; Vancomycin-resistant enterococci.