Abstract:Objective To understand antimicrobial resistance of Providencia rettgeri (P. rettgeri) in a hospital, analyze the genetic characteristics of antimicrobial resistance genes of carbapenem-resistant P. rettgeri (CRPR), and provide theoretical basis for clinical prevention and treatment of infection. Methods Antimicrobial susceptibility testing results of P. rettgeri isolated from this hospital from January 2017 to December 2019 were collected, whole genomes of 3 strains of CRPR were detected through high-throughput sequencing, bioinformatics analysis was adopted to explore genetic characteristics. Results A total of 25 strains of P. rettgeri were isolated, 10(40.00%) of which were carbapenem-resistant strains, 7 strains (28.00%) were isolated from department of neurosurgery, urine was the main specimen source (13 strains, 52.00%). 25 strains were all resistant to ampicillin and amoxicillin, resistance rate was 100.00%. Resistance rates to imipenem, ertapenem and meropenem were 36.00%, 40.00% and 28.00% respectively. Genome sequencing of 3 CRPR strains showed that all of them carried 6 antimicrobial resistance genes, including β-lactams (blaNDM-1, blaOXA-10 and blaTEM-1B), macrolides (mph[A], mph[E], msr[E]), trimethoprim (dfrA1), aminoglycosides (aadA1, aadA5, aph[3″]-Ib, aph[4]-Ia, acc[6']-Ib3, aadB), sulfonamides(sul1), and chloramphenicols(catB8), the genetic structures of the drug-resistant genotypes of blaNDM-1 and blaOXA-10 were IS30-blaNDM-1-bleMBL-trpF-dsbC-orf-groES-groEL-IS91 and aac(6')-Ib3-dfrA1-aadA1-blaOXA-10-catB8-aadB respectively. Conclusion Multidrug resistance of P. rettgeri is serious, and there are many types of drug-resistant genes. It is necessary to strengthen the prevention and control of healthcare-associated infection to prevent the spread of antimicrobial-resistant strains.