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bioRxiv · 10.1101/2021.02.26.433140

Emergence of a Hypervirulent Carbapenem-Resistant Klebsiella pneumoniae Co-harbouring a blaNDM-1-carrying Virulent Plasmid and a blaKPC-2-carrying Plasmid in an Egyptian Hospital

Abstract

The emergence of carbapenem-resistant Klebsiella pneumoniae (CRKP) isolates in Egyptian hospitals has been reported. However, the genetic basis and the analysis of the plasmids associated with CR-hypervirulent-KP (CR-HvKP) in Egypt are not presented. Therefore, we attempt to decipher the plasmids sequences, which are responsible for transferring the determinants of carbapenem-resistance, particularly the blaNDM-1 and blaKPC-2. Out of 34 K. pneumoniae isolates collected from two tertiary hospitals in Egypt, 31 were CRKP. Whole-genome sequencing revealed that our isolates were related to 13 different sequence types (STs). The most prevalent ST was ST101, followed by ST383, and ST11. Among the CRKP isolates, one isolate named EBSI036 has been reassessed using Nanopore sequencing. Genetic environment analysis showed that EBSI036 carried 20 antibiotic resistance genes and was identified as CR-HvKP strain, it harboured four plasmids, namely; pEBSI036-1-NDM-VIR, pEBSI036-2-KPC, pEBSI036-3, and pEBSI036-4. The two carbapenemase genes, blaNDM-1 and blaKPC-2, were located on plasmids pEBSI036-1-NDM-VIR and pEBSI036-2-KPC, respectively. The IncFIB:IncHI1B hybrid plasmid pEBSI036-1-NDM-VIR also carried some virulence factors, including regulator of the mucoid phenotype (rmpA), the regulator of mucoid phenotype 2 (rmpA2), and aerobactin (iucABCD, iutA). Thus, we set out this study to analyse in-depth the genetic basis of pEBSI036-1-NDM-VIR and pEBSI036-2-KPC plasmids. We reported for the first time a high-risk clone ST11 KL47 serotype of CR-HvKP strain isolated from the blood of a 60-year-old hospitalised female patient from the ICU in a tertiary-care hospital in Egypt, which showed the cohabitation of a novel hybrid plasmid coharbouring the blaNDM-1 and virulence genes, besides a blaKPC-2-carrying plasmid. IMPORTANCECRKP had been registered in the critical priority tier by the World Health Organization and became a significant menace to public health. Therefore, we set out this study to analyse in-depth the genetic basis of pEBSI036-1-NDM-VIR and pEBSI036-2-KPC plasmids. Herein, we reported for the first time (to the best of our knowledge) a high-risk clone ST11 KL47 serotype of CR-HvKP strain isolated from the blood of a 60-year-old hospitalised female patient in a tertiary-care hospital from the ICU in Egypt, which showed the cohabitation of a novel hybrid plasmid co-harbouring the blaNDM-1 and virulence genes, besides a blaKPC-2-carrying plasmid. Herein, the high rate of CRKP might be due to the continuous usage of carbapenems as empirical therapy, besides the failure to implement an antibiotic stewardship program in Egyptian hospitals. Thus, this study serves to alert the contagious disease clinicians to the presence of hypervirulence in CRKP isolates in Egyptian hospitals.

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BibTeXRIS

El-Sayed Ahmed, M. A. E.-G., Yang, Y., Yan, B., Chen, G., Hassan, R. M., Zhong, L.-l., Chen, Y., Roberts, A. P., Wu, Y., He, R., Liang, X., Qin, M., Dai, M., Zhang, L., Li, H., Yan, F., Xu, L. Q., Tian, G.-B.. 2021-03-01. Emergence of a Hypervirulent Carbapenem-Resistant Klebsiella pneumoniae Co-harbouring a blaNDM-1-carrying Virulent Plasmid and a blaKPC-2-carrying Plasmid in an Egyptian Hospital. https://doi.org/10.1101/2021.02.26.433140

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