672. Report of a Multi-species Outbreak of VIM-producing Carbapenem-resistant Organisms in a Burn Unit and Subsequent Experience Using Novel β-lactam Antibiotics for Treatment

Abstract Background The incidence of carbapenem-resistant organisms (CROs) has increased over the past 3 decades. Carbapenem-resistance due to metallo-β-lactamases (MBLs) such as Verona integron-encoded metallo-β-lactamase (VIM) are particularly problematic limited treatment options. We describe a multi-species outbreak VIM-producing CROs (VIM CROs) in tertiary care hospital along with our experience using novel β-lactam antibiotics for treatment. Methods performed retrospective chart review after cluster patients burn unit were found have infections VIM CROs. Electronic medical records all CRO isolated between November 2021 and March 2022 reviewed. Data regarding patient characteristics, antimicrobial use, culture results, susceptibility testing, clinical outcomes recorded each patient. Results 8 VIM-mediated wound infections, 5 whom also bacteremic CRO. A gene was identified different species (Pseudomonas aeruginosa 4 Enterobacterales). None received carbapenems prior isolation Among treated cefiderocol, 2 had cefiderocol-resistant 10-20 days starting cefiderocol. combination ceftazidime/avibactam aztreonam, subsequent clearing their infection on follow-up cultures taken from same site. Only one died within 30 initial isolation, developing fungal infection. median Pitt bacteremia score at time 1 (range 0-4) 7 who survived versus 6 died. Conclusion MBLs potential spread throughout units even absence carbapenem selection pressure. Although 60% this study cefiderocol-resistance developed 40% mortality fortunately low group. While newer remain an exciting addition armamentarium, we must diligent monitoring rapid development resistance. Disclosures Thomas R. Talbot, III, MD, MPH, OmniSolve: Board Member Romney Humphries, PhD, D(ABMM), M(ASCP), Accelerate: Advisor/Consultant|Accelerate: Stocks/Bonds|bioMerieux: Advisor/Consultant|IHMA: Advisor/Consultant|Pattern: Advisor/Consultant|Qiagen: Advisor/Consultant|QPex: Advisor/Consultant|Roche: Advisor/Consultant|Specific Diagnostics: Stocks/Bonds|ThermoFisher: Advisor/Consultant|Torus: Advisor/Consultant.