Background: The most common procedure of rhinoplasty is the implantation of a synthetic prosthesis. However, the complications, especially postoperative infection, could lead the suboptimal aesthetic outcome, economic losses and health threats. There is currently little literature providing an incidence of rhinoplasty infection and microbiological and antimicrobial resistance situations.
Methods: Therefore, we performed a retrospective observational study which included 173 patients who received a rhinoplasty from 1 January 2015, to 31 December 2019, in the department of plastic surgery of a tertiary hospital in Guangzhou, China. The samples from the infection site were collected and performed the bacterial culture. The antimicrobial susceptibility testing was performed by VITEK and minimum inhibition concentration testing. The whole-genome sequencing was performed by Illumina Hiseq4000 platform.
Results: We found that eight (4.6%) patients were infected by S. aureus  (6), E. raffinosus  (1) and E. coli  (1), of which are susceptible to most antimicrobials. Remarkably, E. coli  RS1231 was resistant to colistin and polymyxin B which conferred by mcr-1.1  locating on an IncI2 plasmid with 59,170-bp sequence length. Through sequence comparison, we speculate that the pRS1231S-MCR-1 was derived from animal sources. Besides, E. coli  RS1231 belongs to ST131 O25:H4-fimH22 pandemic subclone and phylogroup B2, which can induce a broad variety of infections.
Conclusion: Our study provided a rhinoplasty infection incidence, microbiological and antimicrobial resistance prevalence data, and revealed, to our knowledge, the first case of postoperative infection of rhinoplasty by mcr-1.1 -positive, highly susceptible, and remarkably virulent E. coli  isolate.
Keywords: rhinoplasty, colistin resistance, ST131, mcr-1.1 , Escherichia coli , horizontal gene transfer, virulence