Carbapenemase-producing Enterobacteriaceae digestive carriage at hospital readmission and the role of antibiotic exposure

Epidemiological and bacteriological trends from 2013 to 2023 of carbapenemase-producing enterobacterales (CPE) in a French university hospital: A permanent risk of outbreak

AIM

The aim of this study was to describe the epidemiology and bacteriological trends of carbapenemase-producing Enterobacteriaceae (CPE) at Nantes University Hospital from 2013 to 2023.

METHODS

Potential CPE carriers were prospectively detected, and their contacts were systematically screened for CPE digestive colonization. A retrospective study was conducted from 2013 to 2023 (on patient characteristics) and from 2016 to 2023 (on CPE characteristics). An outbreak was defined as at least one secondary case occurring among contact patients during the same hospitalization, in the same unit, and with the same staff.

RESULTS

All in all, 553 CPE-positive carriers were identified during the study period. Among them, 178 (32 %) were sporadic cases and 100 (18 %) were incidentally detected. Fifty-seven outbreaks were investigated comprising 305 (55 %) secondary cases. The most commonly identified CPE species in outbreaks were Klebsiella pneumonia OXA-48.

CONCLUSION

CPE detection in the hospital was associated mainly with epidemic spread involving a variable number of secondary cases. CPE patients detected incidentally (without specific infection control measures) several days after hospital admission, repatriates and patients with a history of hospitalization abroad are at high risk of in-hospital CPE spread. The number of outbreaks did not decrease during the study period, and more generally, the number of secondary cases tends in some uncontrolled situations to increase, particular when CPE- positive patients are transferred or rehospitalized.

Long-read sequencing reveals genomic diversity and associated plasmid movement of carbapenemase-producing bacteria in a UK hospital over 6 years

Healthcare-associated infections (HCAIs) affect the most vulnerable people in society and are increasingly difficult to treat in the face of mounting antimicrobial resistance (AMR). Routine surveillance represents an effective way of understanding the circulation and burden of bacterial resistance and transmission in hospital settings. Here, we used whole-genome sequencing (WGS) to retrospectively analyse carbapenemase-producing Gram-negative bacteria from a single hospital in the UK over 6 years (n=165). We found that the vast majority of isolates were either hospital-onset (HAI) or HCAI. Most carbapenemase-producing organisms were carriage isolates, with 71 % isolated from screening (rectal) swabs. Using WGS, we identified 15 species, the most common being Escherichia coli and Klebsiella pneumoniae. Only one significant clonal outbreak occurred during the study period and involved a sequence type (ST)78 K. pneumoniae carrying bla NDM-1 on an IncFIB/IncHI1B plasmid. Contextualization with public data revealed little evidence of this ST outside of the study hospital, warranting ongoing surveillance. Carbapenemase genes were found on plasmids in 86 % of isolates, the most common types being bla NDM- and bla OXA-type alleles. Using long-read sequencing, we determined that approximately 30 % of isolates with carbapenemase genes on plasmids had acquired them via horizontal transmission. Overall, a national framework to collate more contextual genomic data, particularly for plasmids and resistant bacteria in the community, is needed to better understand how carbapenemase genes are transmitted in the UK.

Systematic screening for digestive carriage of extended-spectrum β-lactamase-producing Enterobacterales (E-ESBL) at hospital readmission among patients with past history of E-ESBL colonization or infection

BACKGROUND

Extended-spectrum β-lactamase-producing Enterobacterales (E-ESBL) are commensal multidrug-resistant (MDR) bacteria of the digestive tract whose prevalence has risen sharply worldwide and in Europe over the past two decades.

AIM

To assess digestive carriage at hospital readmission of a large cohort of 2509 patients with E-ESBL carriage over a five-year survey; 833 (33%) patients were readmitted at least once.

METHODS

A retrospective, single-centre survey conducted at a tertiary care hospital in France.

FINDINGS

Among patients with several hospital readmissions (range: 2-13), the proportion of patients still E-ESBL-colonized at hospital readmission, detected by systematic screening for E-ESBL colonization, was >80% within an 18-month period after prior hospitalization with the first E-ESBL isolation.

CONCLUSION

There is a need to reconsider the continuation of systematic screening for E-ESBL colonization because of a high rate of patients still colonized at hospital readmission over a long period of time.