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First Report of OXA-181-Producing Enterobacterales Isolates in Latin America
Diego Cuicapuza1,2,3,4, Luis Alvarado5, Norah Tocasca6
1Facultad de Medicina, Universidad Peruana Cayetano Heredia, Lima, Peru.
Abstract:
We characterized five carbapenemase-producing Enterobacterales (CPE) isolates from two health care institutions in Lima, Peru. The isolates were identified as Klebsiella pneumoniae (n = 3), Citrobacter portucalensis (n = 1), and Escherichia coli (n = 1). All were identified as blaOXA-48-like gene carriers using conventional PCR. Whole-genome sequencing found the presence of the blaOXA-181 gene as the only carbapenemase gene in all isolates. Genes associated with resistance to aminoglycosides, quinolones, amphenicols, fosfomycins, macrolides, tetracyclines, sulfonamides, and trimethoprim were also found. The plasmid incompatibility group IncX3 was identified in all genomes in a truncated Tn6361 transposon flanked by ΔIS26 insertion sequences. The qnrS1 gene was also found downstream of blaOXA-181, conferring fluoroquinolone resistance to all isolates. CPE isolates harboring blaOXA-like genes are an increasing public health problem in health care settings worldwide. The IncX3 plasmid is involved in the worldwide dissemination of blaOXA-181, and its presence in these CPE isolates suggests the wide dissemination of blaOXA-181 in Peru. IMPORTANCE Reports of carbapenemase-producing Enterobacterales (CPE) isolates are increasing worldwide. Accurate detection of the β-lactamase OXA-181 (a variant of OXA-48) is important to initiate therapy and preventive measures in the clinic. OXA-181 has been described in CPE isolates in many countries, often associated with nosocomial outbreaks. However, the circulation of this carbapenemase has yet to be reported in Peru. Here, we report the detection of five multidrug-resistant CPE clinical isolates harboring blaOXA-181 in the IncX3-type plasmid, a potential driver of dissemination in Peru.
Insights
Five carbapenemase-producing Enterobacterales (CPE) isolates in Peru carried the blaOXA-181 gene on an IncX3 plasmid. This finding highlights the potential for widespread dissemination of this concerning multidrug-resistant bacteria in the region.
Area of Science:
- Microbiology and Infectious Diseases
- Antimicrobial Resistance
- Genomics
Background:
- Carbapenemase-producing Enterobacterales (CPE) are a growing global health threat.
- The OXA-181 carbapenemase, a variant of OXA-48, is increasingly reported worldwide.
- Detection and understanding of OXA-181 dissemination are crucial for clinical management and public health.
Purpose of the Study:
- To characterize carbapenemase-producing Enterobacterales (CPE) isolates from healthcare institutions in Lima, Peru.
- To identify the specific carbapenemase genes and associated resistance mechanisms present in these isolates.
- To investigate the genetic elements, particularly plasmids, involved in the dissemination of carbapenemase genes in Peru.
Main Methods:
- Isolation and identification of five CPE strains (Klebsiella pneumoniae, Citrobacter portucalensis, Escherichia coli).
- Conventional PCR for detection of blaOXA-48-like genes.
- Whole-genome sequencing to identify carbapenemase genes, other resistance genes, and mobile genetic elements.
Main Results:
- All five isolates harbored the blaOXA-181 gene as the sole carbapenemase determinant.
- Isolates exhibited resistance to multiple antibiotic classes, including aminoglycosides, quinolones, and tetracyclines.
- The IncX3 plasmid, containing a truncated Tn6361 transposon and the qnrS1 gene, was present in all isolates, suggesting its role in blaOXA-181 dissemination.
Conclusions:
- This study reports the first detection of blaOXA-181-carrying CPE in Peru.
- The presence of the IncX3 plasmid highlights a potential mechanism for the widespread dissemination of OXA-181 in the region.
- These findings underscore the urgent need for surveillance and control measures against multidrug-resistant CPE in Peru.
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