Comparative Phenotypic and Genomic Features of Staphylococci from Sonication Fluid of Orthopedic Implant-Associated Infections with Poor Outcome.

spp. remain the leading biofilm-forming agents causing orthopedic implant-associated infections (OIAI). This is a descriptive study of phenotypic and genomic features identified in clinical isolates of and coagulase-negative (CoNS) recovered from OIAIs patients that progressed to treatment failure. Ten isolates were identified by matrix-time-of-flight laser-assisted desorption mass spectrometry (MALDI-TOF-MS) and tested for antibiotic susceptibility and biofilm formation. Genotypic characteristics, including, MLST (Multi Locus Sequence Typing), , virulence and resistance genes were assessed by whole-genome sequencing (WGS). All harbored , , and multiple resistance genes for aminoglycosides and quinolones. All MRSA were strong biofilm producers harboring the complete ADBC and R operon. Seven CoNS isolates comprising five species (, , , and ) were analyzed, with detected in five isolates. (isolate 95), and were unable to form biofilm and did not harbor the complete operon. High variability of adhesion genes was detected, with , , ADBC , and 256 being the most common. In conclusion, MRSA and CoNS isolates carrying genes for biofilm production, and resistance to β-lactam and aminoglycosides are associated with treatment failure in OIAIs.