Prevalence and characterization of Carbapenem-Resistant Enterobacterales among inpatients and outpatients in Skikda, Algeria.

Introduction: The spread of Carbapenemase-producing Enterobacterales (CPEs) has become a significant concern in Algeria, with limited data available on their presence in community settings. This research investigated the resistance mechanisms of carbapenem-resistant Enterobacterales (CREs) collected from hospitals and the community in Skikda city, Algeria, between December 2020 and June 2022.

Methodology: The study collected Enterobacterales strains resistant to ertapenem from inpatient and outpatient populations. An automated system was used for identification and antibiotic susceptibility testing. β-lactamase production was evaluated through phenotypic tests and confirmed by standard PCR. Lastly, the carbapenemase genes were sequenced using the Sanger method.

Results: 17 CRE were isolated, with 9 from inpatients and 8 from outpatients. These isolates belonged to four species: Klebsiella pneumoniae (n = 8), Escherichia coli (n = 6), Enterobacter cloacae (n = 1), and Proteus mirabilis (n = 1). Of 15 CPEs, 11 were extended-spectrum β-lactamases (ESBLs) positive, 5 were plasmid-mediated cephalosporinase (AmpC) positive, and 1 harbored all three β-lactamases. All metallo-β-lactamase-producing strains carried the New Delhi metallo-beta-lactamase gene (blaNDM), including 5 NDM-1 and 7 NDM-5 variants. The presence of blaOXA-48 and blaOXA-244 was observed in one outpatient strain each. NDM was associated with Cefotaximase Munich (CTX-M) ESBL in 8 isolates, while Cephamycinase (CMY) was detected in 3 NDM-5-producing E. coli.

Conclusions: This research highlights the rising prevalence of carbapenemases NDM-1 and NDM-5 among inpatients and outpatients and supports the notion that OXA-48 is becoming increasingly widespread beyond Algerian hospitals.