Genomic characterization and clinical evaluation of prosthetic joint infections caused by <i>Cutibacterium acnes</i>

Prosthetic joint infection (PJI) is a rare complication after arthroplasty surgery. The infection seldom resolves without a combination of both surgical and antibiotic treatment and can cause significant suffering among affected patients. <i>Cutibacterium acnes</i> is a common skin bacterium that is most often found in shoulder PJIs but can also infect other prostheses. In this study, we conducted a review of patients with previously verified PJIs involving <i>C. acnes</i> in hip or shoulder prostheses, along with a genomic analysis of the bacteria causing the infections. The majority of patients had successful outcomes. We did not identify any specific phylogenetic lineage or specific molecular signature of virulence factors among these PJI-associated <i>C. acnes</i> isolates that seemed to be associated with increased potential to cause infection among this species. This indicates that <i>C. acnes</i> isolated from PJIs originates from the patients' own skin microbiome and is inoculated during the arthroplasty surgery.