Identifying Common Pathogens in Periprosthetic Joint Infection and Testing Drug-resistance Rate for Different Antibiotics: A Prospective, Single Center Study in Beijing.
OBJECTIVE
The aim of this study is to identify the common microorganisms causing PJI as well as the drug-resistant spectrum for each microorganism, to help orthopaedic surgeons to choose appropriate antibiotics.


METHOD
One hundred and sixty patients who suffered from failure of primary or revision total hip or knee arthroplasty for different reasons were prospectively recruited. These patients underwent revision or re-revision total hip or knee arthroplasty in our institution between August 2013 to August 2016. The details of patients' medical history and comprehensive physical examination, as well as demographic data were recorded precisely. Routine blood test results, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), high sensitive C-reactive protein (hs-CRP), interleukin-6 (IL-6) levels, and synovial leukocyte counts were collected. Additionally, aspiration was conducted during surgery to avoid pollution unless when PJI was strongly suspected, in which case, joint puncture and aspiration were conducted before surgery. Intraoperatively, the implant-surrounding tissue and the prosthesis were collected under aseptic conditions. Postoperatively, the prosthesis, implant-surrounding tissue and synovium were sent to the laboratory immediately. The sonicate extraction (the prosthesis was sent for ultrasound sonication first), implant surrounding tissue and synovium were sent for microbiologic culture, and the implant-surrounding tissue was also sent for pathological examination. The isolated bacteria strains and drug-resistance rates for each pathogen for different antibiotics were presented.


RESULTS
There were 59 PJI cases in the infectious group and 101 cases in the non-infectious group (PJI is diagnosed according to the diagnosing criteria from the Workgroup of the Musculoskeletal Infection Society). Of 69 strains of pathogens isolated, Gram-positive bacterium is the most common pathogenic bacteria causing PJI (60, 86.96%). Staphylococcus epidermidis and Staphylococcus aureus played an important role as well, followed by Gram-negative bacteria (8, 11.59%) and fungus (1, 1.45%). Penicillin (78.57%), erythromycin (66.67%) and clindamycin (44.74%) showed high antibiotic resistance rate. In addition, the second-generation cephalosporin, usually as the prophylactic antibiotic, resistance rate was high (20%) as well. Fortunately, no vancomycin-resistant bacteria were discovered in the current study.


CONCLUSION
This study provides some information on the most common pathogens in our institution and the selection of antibiotics in the perioperative period in northern China. Cefuroxime and clindamycin might not be appropriate for use as prophylactic antibiotics in revision total knee or hip arthroplasty. Vancomycin is ideal for empiric antibiotic use in suspected PJI cases because of the low drug-resistance rate.
['Li|Zhang-Lai|ZL|', 'Hou|Yun-Fei|YF|', 'Zhang|Bao-Qing|BQ|', 'Chen|Yi-Fan|YF|', 'Wang|Qi|Q|', 'Wang|Kai|K|', 'Chen|Zhao-Yu|ZY|', 'Li|Xiao-Wei|XW|', 'Lin|Jian-Hao|JH|']
D000368:Aged D019644:Arthroplasty, Replacement, Hip D019645:Arthroplasty, Replacement, Knee D015373:Bacterial Typing Techniques D024881:Drug Resistance, Bacterial D005260:Female D006090:Gram-Negative Bacteria D016905:Gram-Negative Bacterial Infections D006094:Gram-Positive Bacteria D016908:Gram-Positive Bacterial Infections D006622:Hip Prosthesis D006801:Humans D007720:Knee Prosthesis D008297:Male D008826:Microbial Sensitivity Tests D008875:Middle Aged D011446:Prospective Studies D011475:Prosthesis Failure D016459:Prosthesis-Related Infections D012086:Reoperation
Pathogen Periprosthetic joint infection Drug-resistance