Abstract
PURPOSE: Osteoarticular infections (OAI) are serious clinical conditions with Staphylococcus aureus and Coagulase-negative Staphylococcus (CoNS) responsible for up to two-thirds of cases. This work aimed to compare the epidemiological, clinical, and microbiological characteristics of OAI caused by S. aureus versus CoNS to aid in clinical management and infection control strategies. METHODS: A single-centre retrospective study was performed at the Centro Hospitalar e Universitário de Coimbra for the period of January 2011 to December 2021. A total of 458 cases of OAI were gathered. Data was retrieved from medical records and statistical analysis was performed with SPSS. RESULTS: S. aureus accounted for 60.7% of infections, followed by S. epidermidis (29.9%). Independent risk factors for S. aureus infections included being male (p < 0.001; OR = 0.47) and a history of osteomyelitis (p < 0.001; OR = 0.18). In contrast, CoNS infections were associated with older age (p = 0.018), carrying a prosthetic device (p < 0.001; OR = 2.92), and a prior periprosthetic infection (p = 0.023; OR = 1.86). Both groups exhibited significant antimicrobial resistance, with CoNS showing greater resistance to gentamicin, linezolid, teicoplanin and trimethoprim-sulfamethoxazole, while S. aureus was more commonly resistant to clindamycin. CONCLUSION: Our findings show the distinct characteristics of OAI caused by S. aureus and CoNS, highlighting the need for targeted risk factor management and tailored empiric antibiotic therapy to reduce incidence and improve outcomes.