Virulence factors of Proteus mirabilis clinical isolates carrying blaKPC-2 and blaNDM-1 and first report blaOXA-10 in Brazil

Proteus mirabilis is one of the main pathogens that cause urinary tract infections. Therefore, the aim of this study was to analyze and compare the genetic profile of 36 clinical isolates of P. mirabilis that carry and do not carry the blaKPC and blaNDM gene with respect to virulence factors (mrpG, pmfA, ucaA, nrpG and pbtA) and antimicrobial resistance (blaVIM,blaIMP, blaSPM, blaGES,blaOXA-23-like, blaOXA-48-like, blaOXA-58-like and blaOXA-10-like). The virulence and resistance genes were investigated by using PCR and sequencing. ERIC-PCR typing showed that the isolates showed multiclonal dissemination and high genetic variability. The gene that was most found blaOXA-10-like (n = 18), followed by blaKPC (n = 10) and blaNDM (n = 8). To our knowledge, this is the first report of blaOXA-10 in P. mirabilis in Brazil, as well as the first report of the occurrence of P. mirabilis co-carrying blaOXA-10/blaKPC and blaOXA-10/blaNDM. The blaNDM or blaKPC carrier isolates showed important virulence genes, such as ucaA (n = 8/44.4%), pbtA (n = 10/55.5%) and nrpG (n = 2/11.1%). However, in general, the non-carrier isolates of blaKPC and blaNDM showed a greater number of virulence genes when compared to the carrier group. Clinical isolates of P. mirabilis, in addition to being multi-drug resistant, presented efficient virulence factors that can establish infection outside the gastrointestinal tract.