Epidemiological and Molecular Study of Providencia Rettgeri Outbreak at an University Hospital During the Covid-19 Reference Center

Abstract In 2014, Brazil detected New Delhi metallo-β-lactamase (NDM)-producing Enterobacterales from a Providencia rettgeri isolate obtained through surveillance swabs in the Southern region. Subsequently, various species have reported several NDM enzymes. However, comprehensive data on the current epidemiology of NDM-producing P.rettgeri in Brazil remains limited. This study, aimed to provide a detailed characterization of the phenotypic, genotypic and epidemiological profile of clinical isolates of P. rettgeri NDM. From April 2020 to December 2022, 18 carbapenem-resistant P. rettgeri strains, previously identified using Vitek2®, were isolated at the University Hospital of Londrina. Resistance and virulence genes were assessed through genetic analysis usig ERIC PCR and NextSeq (Illumina) sequencing. Statistical analysis was conducted using SPSS version 2.0. Genomic analysis confirmed the presence of β-lactamase blaNDM-1, blaOXA-1. All isolates showed the presence of the NDM gene and genetic similarity above 90% between isolates. Clinical parameters of patients infected with P. rettgeri exhibited significant association with mechanical ventilation, prior use of carbapenems, and polymixins. We also report a significant association between P. rettgeri infection and death outcome. This study characterizes NDM-1 metallo-β-lactmases isolates, among P. rettgeri isolates from patients at the University Hospital (HU), during the COVID-19 pandemic. The emergence of this novel resistance mechanism among P. rettgeri poses a significant challenge, limiting the therapeutic optins for infections in our hospital.