235. Next-Generation Sequencing for Investigation of Hospital Outbreak of Carbapenem--Resistant Klebsiella pneumoniae

Abstract Background Carbapenem--resistant Enterobacteriaceae constitute an urgent public health problem worldwide. In 2018, carbapenem--resistant Klebsiella pneumoniae (CR-KP) caused outbreaks of infection in 4 intensive-care units (ICUs)in a tertiary-care hospital in Egypt. We aimed to identify the clonal relatedness of isolates by whole genome (WGS). Methods Identification and antibiotic susceptibility testing was done by VITEK-2. Eleven isolates showed identical resistance pattern (resistant to Amikacin, gentamicin, Imipenem, meropenem, levofloxacin, and Piperacillin/Tazobactam) and were susceptible only to colistin. Caba-NP test was positive for carbapenemase production. The 11 isolates were studied by WGS by Illumina Miseq in a reference lab in Cairo University Hospital. Results In only one ICU, WGS identified 4 outbreak isolates of CR-KP that group together as a tight clonal cluster, suggestive of intra-ward transmission event. The outbreak isolates belonged to MLST 147. All isolates carried blaCTXM-15, blaoxa-48, and blaNDM1 encoding ESBL and carbapenemase activity. Other identified resistance genes were Str, AadA, MsrE, Tet, and DfrA, encoding resistance to aminoglycosides, macrolide–lincosamide–streptogramin, tetracycline and trimethoprim/sulphonamides. Virulence genes included Yersiniabactin, aerobactin, rmpA, rmpA2 and wzi64, which has been associated with pathogenicity and hypervirulent K. pneumoniae lineages. No clonal relationships were identified between the isolates from other ICUs. Conclusion WGS is a powerful tool that goes beyond high-resolution tracking of transmission events into identifying the genetic basis of drug-resistance and virulence. Disclosures All authors: No reported disclosures.