Microbiological Characteristics and Clinical Outcomes, Including Mortality, Among Patients with Prosthetic Joint Infection: A Retrospective Study

Aim: Prosthetic joint infections (PJIs) are severe complications of joint arthroplasty, and their management has become increasingly complex in the era of antimicrobial resistance. This study aimed to evaluate the microbiological characteristics and clinical outcomes of PJIs in a high-resistance clinical setting.Material and Methods: This retrospective study included 74 patients diagnosed with PJI between January 2019 and June 2022 at a tertiary care hospital. Microbiological findings, antimicrobial resistance patterns, treatment outcomes, recurrence, and mortality were analyzed.Results: Microbiological growth was detected in 75.0% (n=54) of cases; 25.0% (n=18) were culture-negative. Among the 84 isolated pathogens, gram-negative bacteria accounted for 55.9% (n=47) and predominated particularly in early-onset infections. Staphylococcus aureus was the most frequently identified pathogen; however, carbapenem-resistant gram-negative organisms were common and were significantly associated with treatment failure (p=0.004) and mortality (p=0.011). Polymicrobial infections (35.2%, n=19) were independently associated with recurrence (p=0.001) and increased the odds of mortality (OR=7.91, 95% CI=1.42-52.61, p=0.017). Treatment success was significantly higher in patients with primary knee prostheses compared with hip or revision prostheses (p=0.029).Conclusion: PJIs in this study were characterized by a high burden of gram-negative and multidrug-resistant pathogens. Carbapenem resistance and polymicrobial etiology were key determinants of adverse outcomes, emphasizing the critical role of local antimicrobial resistance surveillance in guiding empirical treatment decisions.