Isolation of a carbapenemase producing Klebisiella in the NUH hospital

A K. pneuomoniae was isolated from rectal swabs taken to screen for multi-drug resistant Enterobacteriaceae carriage in a Libyan patient transferred to the Queens Medical Centre campus of Nottingham University Hospitals NHS Trust for treatment on severe trauma injuries. Methods: Screening was performed on rectal swabs plated onto MacConkey agar plates with a 10mg ertapenem disc. Antibiotic breakpoints and the modified Hodge test were performed on the suspect colony. Molecular testing was performed using two in-house multiplex PCRs to detect the presence of the most commonly encountered carbapenemase genes. The genome sequence of the isolate was obtained using the Illumina HiSeq platform, assembled and annotated. The antimicrobial resistance gene pool of the organism was determined using the CARD database, and plasmids identified using the PlasmidFinder programme. Results: The K. pneuomonaie isolate was phenotypically confirmed as a carbapenemase producer with resistance to meropenem (>32 µg/ml), piptazobactam (>256 µg/ml), trimethoprim, and co-amoxiclav. The genome sequence identified the isolate as belonging to the globally disseminated ST147 highly-pathogenic, multi-drug resistant lineage. The presence of at least 4 plasmids was determined including pOXA-48. The isolate contained approximately 0.5Mbp of extra-chromosomal DNA and 68 ORFs associated with antimicrobial resistance including Shv-11 and Oxa-30. Conclusion: This is the first report of the characterisation of a K. pneumonia ST147 Oxa-48 producing isolate in the United Kingdom. The study highlights the impressive array of antimicrobial associated genetic elements acquired by this important globally emerging organism, and provides a reference point for comparison of further UK isolates.