Who should be screened for carbapenemase-producing Enterobacterales and when? A systematic review

Carbapenemase-producing Enterobacterales (CPE) cases increases every year in Denmark and the proportion of CPE-positive cases with a travel history decreases. Several epidemiological links show transmission in Danish healthcare setting indicating infection prevention and control challenges and raising questions about the Danish CPE screening protocol. The aim of this review was to identify additional risk factors to those described in the Danish CPE-screening protocol in order to detect the Danish CPE-positive patients and thereby reduce the risk of transmission and outbreaks. A systematic literature search was conducted in PubMed, Embase and Cochrane Library during March 2022. A total of 1487 articles were screened, and 19 studies were included. Retrieved studies dealt with patients with laboratory-confirmed CPE (colonization and/or infection) and associated risk factors. Antimicrobial therapy, especially broad-spectrum antimicrobial agents, prior or current hospitalization of approximately one week in ICU and 20-28 days in other wards and travel history with or without hospitalization abroad were significant risk factors associated with CPE acquisition. Comorbidities and invasive procedures were identified as risk factors, but without identifying specific comorbidities or invasive procedures associated with risk for CPE-acquisition. This study suggests the need to develop an additional algorithm for CPE-screening in Denmark. In addition to risk-based screening on admission, screening of inpatients should be considered. The screening protocol might include screening of inpatients with comorbidities who are hospitalized >1 week in ICU or >3 weeks in other wards and who have previously received or currently are receiving antibiotic treatment. Further research is needed to develop a new CPE-screening algorithm.