Abstract
Aim
Over the past three years, roughly 100,000 hip and knee replacements have been performed by the Brazilian Public Healthcare System. Prosthetic joint infection (PJI) is expected to range between 1% to 10% after primary and revisions joint arthroplasties, respectively. So far, there have been no published national PJI data which would be helpful at developing local preventive strategies and guide surgeons and clinicians. We aimed at describing the epidemiological, clinical and microbiological PJI results of a national and collaboration study among infectious diseases specialists and orthopaedic surgeons, including academic, public and private institutions.
Method
We prospectively enrolled patients with PJI in a national cohort study among 12 hospitals from 6 different States to describe host, pathogens, diagnosis, surgery strategies adopted (according to the standard hospital-based guideline) and outcome after 1- and 2-years follow-up. PJI was defined using the IDSA criteria (Osmon D, et al. Clin Infect Dis. 2013). Patients were enrolled from July 2013 to December 2015.
Results
Overall, 234 patients undergoing hip, knee and shoulder (n=3) arthroplasty were eligible; 35 were excluded: did not fulfil the inclusion criteria (n=14), withdrawal informed consent (n=11) and early lost to follow-up (n=10). A total of 199 were available for analysis. Twenty-two (11%) patients died during the follow-up, most of which (95%) occurred within 1 year of PJI diagnosis. In the one-year (12 patients lost to follow-up) and two-year (18 patients lost to follow-up) post-diagnosis analysis, overall treatment failure occurred in 13.3% (n=22/166), and 17% (n=25/147). Knee and hip rate failure in the 1- and 2-year follow up were 12.2% (n=9/74), 15.4% (n=14/91), and 16.2% (n=11/68), 18.2% (n=14/77), respectively. Debridement with implant retention (DAIR), one-stage exchange, two-stage exchange, and arthrodesis was performed in 44.7%, 25.4%, 22.3%, 7.6% respectively. Failure rates for DAIR, one-stage exchange, two-stage exchange, and arthrodesis after 1- and 2-year follow-up were 24.2% (n=16/66), 4.3% (n=2/46), 9.8% (4/41), 0% (n=0/15), and 28.6% (n=16/56), 4.8% (n=2/42), 15.8% (n=6/38), 0% (n=0/15), respectively. Microbial diagnosis yielded positive culture in 71.7%. Staphylococcus aureus (34%), coagulase-negative staphylococci (28%), Pseudomonas aeruginosa (17%) were more prevalent. Polymicrobial PJI were diagnosed in 32.8%.
Conclusions
This is so far the largest Brazilian cohort of patients with PJI showing an overall 2-years failure-free survival rate of 83%, in which DAIR is the most frequent and less successful strategy, single-stage exchange seems to be a growing surgical option. Polymicrobial and non-fermenting Gram-negative bacilli and Enterobacteriacae is frequent.