Evaluation of susceptibility to colistin, fosfomycin and mecillinam in carbapenemase-producing Enterobacterales isolated in Marrakech in 2023

Wissal  Nordinel; Ayoub El  Ame; Taoufik  Benhoumich; Asmaa Lamrani  Hanchi; Nabila  Soraa

doi:10.18502/ijm.v18i3.21657

Wissal Nordinel Department of Biology, Mohamed VI University Hospital Center, Marrakech, Morocco
Ayoub El Ame Department of Biology, Mohamed VI University Hospital Center, Marrakech, Morocco
Taoufik Benhoumich Department of Microbiology, Faculty of Medicine, Cadi Ayyad University, Marrakech, Morocco
Asmaa Lamrani Hanchi Department of Microbiology, Faculty of Medicine, Cadi Ayyad University, Marrakech, Morocco
Nabila Soraa Laboratory of Microbiology, University Hospital Mohamed VI, Faculty of Medicine and Pharmacy, Cadi Ayyad University, Marrakech, Morocco

DOI: https://doi.org/10.18502/ijm.v18i3.21657

Keywords: Enterobacterales; Carbapenem-resistant Enterobacterales; Drug resistance; Bacterial; Colistin; Fosfomycin

Abstract

Background and Objectives: Carbapenemase-producing Enterobacterales (CPE) constitute a critical public health concern due to multidrug resistance and limited available treatment options. This study aimed to assess the in vitro susceptibility of CPE isolates to colistin, fosfomycin, and mecillinam.

Materials and Methods: Prospective study was conducted in 2023 at Mohammed VI University Hospital, Marrakech. A total sample of 180 non-duplicate CPE isolates were collected and identified by standard microbiological methods. Antimi- crobial susceptibility testing was performed following recommended guidelines.

Results: Among the isolates, Klebsiella pneumoniae (60%) and Escherichia coli (14%) predominated. The most common carbapenemase was NDM (62%), followed by OXA-48 (26%) and co-producers (11%). Most isolates were obtained from intensive care (32%), plastic surgery (13%), and neonatology (12%) units. Skin and soft tissue (43%) and bloodstream (21%) were the predominant infected sites. Resistance rates were 25% for colistin, 48% for fosfomycin, and 64% for mecillinam, with frequent co-resistance to fluoroquinolones, aminoglycosides, and cotrimoxazole.

Conclusion: The high prevalence of NDM-producing Klebsiella pneumoniae and significant resistance to last-line agents suggest the urgent need for antimicrobial stewardship, optimized therapeutic strategies, and strengthened regional surveil- lance.