Increased Involvement of Staphylococcus epidermidis in the Rise of Polymicrobial Periprosthetic Joint Infections.

ABSTRACT

BACKGROUND: In this study, we aimed to analyze the temporal distribution of polymicrobial periprosthetic joint infections (PJIs), while also evaluating the patient risk factors associated with these infections following total joint arthroplasty at our institution across 2 distinct periods. METHOD: This retrospective cross-sectional study evaluated 259 patients who had knee or hip PJI from 2001 to 2006 and 2018 to 2022. A PJI was diagnosed using the 2018 International Consensus Meeting criteria. We utilized the Polymicrobial Pathogens' Co-occurrence Network Analysis, a novel approach that leverages network theory to map and quantify the complex interplay of organisms in PJIs. RESULTS: Of the 259 patients who had polymicrobial PJI, 58.7% were men, with mean age 67 years (range, 24 to 90). Of the 579 identified pathogens, Staphylococcus epidermidis was the most common (22.1%), followed by Staphylococcus aureus (9.0%) and Cutibacterium acnes (7.8%). The co-occurrence analysis indicated that Staphylococcus epidermidis frequently coexisted with Cutibacterium acnes (26 cultures) and Staphylococcus capitis (22 cultures). A notable increase in body mass index from 27.7 ± 4.4 in 2001 to 2006 to 29.7 ± 6.2 in 2018 to 2022 was observed (P = .001). Moreover, infections from Staphylococcus epidermidis, Cutibacterium acnes, and Staphylococcus capitis saw a significant uptick (P < .001). CONCLUSIONS: The study shows that from 2001 to 2022, there was a significant change in the pathogens responsible for polymicrobial PJIs, particularly an increase in Staphylococcus epidermidis, Cutibacterium acnes, and Staphylococcus capitis. Alongside these microbial changes, there was a rise in body mass index and shifts in comorbid conditions, such as more renal disease and fewer cases of congestive heart failure. These changes highlight the dynamic interplay between host and microbial factors in the pathogenesis of polymicrobial PJIs, necessitating adaptive strategies in both surgical and postoperative care to mitigate the rising tide of these complex infections.