Different microbial and resistance patterns in primary total knee arthroplasty infections – a report on 283 patients from Lithuania and Sweden

Abstract

Background The microbiology and the susceptibility patterns of infected total knee arthroplasties (TKAs) vary depending on demographic, local antimicrobial stewardship, and surgical factors. We wanted to compare the recent microbial profile and antimicrobial resistance pattern in revisions due to infections after primary TKAs in Sweden and Lithuania. Our hypothesis was that there is a difference in bacteriology and resistance pattern based on patient related, societal and local hospital factors as almost similar praxis have been applied for TKA surgery, short term systemic prophylaxis and routine use of local gentamicin containing bone cement. Methods Primary TKAs revised for the first time due to verified or suspected infection were collected nationwide in Sweden during 2018, and in Lithuania between 2011 and 2020 from a single major TKA revision centre in Kaunas. We identified 202 TKAs in Sweden from the Swedish Knee Arthroplasty Register and 84 from Kaunas revised due to infection. We collected available culture reports and evaluated the type of microorganisms with antimicrobial resistance pattern at revision. Results The majority of the infected cases in Sweden were early-type prosthetic joint infection (PJI) (44%), whereas late-type PJI (52%) were more common in the Kaunas cases. Gram-positive bacteria prevailed in both Sweden (55%) and Lithuania (80%). Staphylococcus aureus was the most frequent organism identified in both countries (33% in Sweden and 34% in Lithuania). More polymicrobial infections were observed in Sweden than in Lithuania (16 and 6% respectively). Methicillin resistance in Staphylococcus aureus and coagulase-negative staphylococci were higher in Lithuania (4/28 and 19/29) than in Sweden (1/42 and 9/41). Conclusions The type of infections, microbial profile, and drug resistance pattern differed between Sweden and Lithuania. Societal and local hospitals factors with emerging resistance in Lithuania are the most plausible explanation for the difference. Lack of complete data on a national level in Lithuania underlines the importance of adding microbiology of PJIs in implant registers for national aggregation and allow cross country comparisons.

Assessment of antimicrobial mismatches in empirical treatment in early PJI after aseptic revision arthroplasty

“… 15 Similar to previous reports, we found that the above mentioned microorganisms were mainly seen as part of polymicrobial PJI. 5 , 13 , 16 Polymicrobial PJI was significantly associated with antimicrobial mismatch of the empirical treatment in our cohort. For unknown reasons, polymicrobial PJI was significantly more often seen in RUMC, despite correcting for the difference in patients and surgical characteristics between the hospitals.…”

“…Enterococci (16%), corynebacteria (18%) and GNB (31%) were more often seen as causatives of PJI in our cohort than is observed in PJI after primary arthroplasty. 4 , 13 , 14 Although some researchers question the relevance of Corynebacterium spp. as causative microorganisms in PJI, Corynebacterium spp.…”

“…In our cohort, 31% of the PJIs were caused by GNB, which is a higher rate of GNB PJI than observed in PJI after primary arthroplasty. 13 , 21 As SMK and RUMC are both tertial referral centres, more complex cases can be admitted there, which contribute to the risk of more complex PJIs such as polymicrobial and GNB PJI. There is a concern that the prognosis of GNB PJI is less favourable than the prognosis of PJI caused by Gram-positive bacteria, although recent studies show contradictory results.…”

Temporal Trends in Deep Surgical Site Infections After Six Orthopaedic Procedures Over a 12-year Period Within a US-based Healthcare System

“…The overwhelming majority of infections after most procedures were caused by Gram-positive cocci, consistent with previous studies. [28][29][30] When looking across the study years, decreasing trends for S aureus specifically were observed for hip fracture repair, shoulder arthroplasty, and spine surgery; a lower rate over time was also observed for ACLR and elective THA, but these were not statistically significant. A recent meta-analysis found S aureus screening and decolonization procedures to be associated with a lower risk of infection after orthopaedic procedures.…”

Microbiological Trends and Antibiotic Susceptibility Patterns in Patients with Periprosthetic Joint Infection of the Hip or Knee over 6 Years

“…In addition, identification of the causative pathogen might not be possible in all cases, especially for those patients with culture-negative PJI knowledge of epidemiological data, and antibiotic susceptibilities of the causative pathogens might be helpful to prevent recurrence of PJI. Here, Sebastian et al described in this context differences in the microbiological profiles of patients with PJI between Sweden and Lithuania, with a higher rate of methicillin-resistant S. aureus in Lithuania than in Sweden, outlining the need for further data for better comparison [ 11 ].…”