Periprosthetic joint infection (PJI) is nowadays the most important problem leading to failure in primary and revision total knee (TKA) and total hip arthroplasty (THA), therefore accurate diagnosis of PJI is necessary. We evaluated a commercial multiplex PCR system1 for diagnosis of PJI in joint aspiration fluids prior to surgery. A total of 32 patients were included in the study. Twenty-four patients had TKA and eight had THA. Joint aspiration fluids were examined by standard bacteriological procedures. Excess material of joint aspirates was frozen at −20°C until testing by multiplex PCR1. Inclusion criteria were a minimum leucocyte count of 2.000 per ml and at least 60% of polymorphonucleaur neutrophils (PNN) in the joint aspiration fluid.Aim
Method
The frequency of arthroplasty among older people is increasing. Taking care of Prosthetic Joint infection (PJI) in this specific population is a challenge. The purpose of this multicentric retrospective study was to evaluate the bacterial epidemiology of hip and knee PJI in octogenarians and nonagenarians over ten years. Data were collected using two softwares* in each of the 4 Centers participating. Inclusion criteria: age ≥ 80 years PJI (knee or hip) between January 2007 and December 2016 microbiological data available (strains isolated from osteo-articular samples) Bacterial identification: biochemical methods, followed by Malditof since 2009. For Staphylococcus aureus, Pseudomonas aeruginosa and Enterobacteriaceae, resistance profiles to antibiotics frequently used in PJI were collected. Antimicrobial susceptibility testing: disk diffusion (recommendations: French Society of Microbiology yearly updated).Aim
Method
According to Tsukuyama classification, late acute hematogenous prosthesis joint infections (PJI) should be treated with debridement and implant retention (DAIR). We report here a recurrent Salmonella Dublin hip prosthesis infection. Through this case, we show how a recurrence of chronic PJI may have an acute clinical presentation leading to an inadequate surgical treatment. Case report. On May 2011, a 74-year-old woman with bilateral hip prostheses (implanted in 1998 (right) and 2001 (left)), was admitted to intensive care for sepsis and pain of her left hip. Blood cultures and a joint aspiration of the left hip yielded pure cultures of S.Dublin. The patient had a recent history of febrile diarrhea after consuming dubious meat. The patient underwent DAIR followed by a six-week antibiotherapy. Three years later, she presented to the emergency room for an acute onset febrile PJI of the right hip. The patient underwent DAIR of the right hip. Blood cultures, joint aspiration fluid, and all intraoperative periprosthetic tissue samples yielded S.Dublin. Colonoscopy and abdomen ultrasound were negative. The patient received two weeks of intravenous combined antibiotherapy followed by oral antibiotics for further 10 weeks. Six weeks post operatively, the surgical wound was healed and the patient walked normally. One year later, the patient was referred by her primary care practitioner for night fevers without local signs or dysfunction of her prostheses. Radioleucoscintigraphy showed right hip inflammation. Bilateral hip biopsies were nevertheless performed, yet S. Dublin was recovered solely from the right hip biopsy. A one-stage exchange of the right hip was performed. All intraoperative periprosthetic tissue samples yielded S.Dublin. A six-week-combined antibiotherapy was undertaken. One year later, the patient appeared free of infection and walked normally.Aim
Method
The diagnosis of prosthetic joint infections (PJI) represents a critical challenge for orthopedic surgeons and infectious disease specialists. The diagnosis of PJI is often delayed because non-invasive assays lack sensitivity and specificity. A novel multiplex immunoassay detecting antibodies against Staphylococci, Propionibacteria and Streptococcus agalactiae was developed and its performance evaluated in a prospective, multicenter, non-interventional study. The Luminex-based assay measures serum IgG against a proprietary panel of recombinant purified antigens from Staphylococcus aureus, Staphylococcus epidermidis, Staphylococcus lugdunensis, Streptococcus agalactiae and Propionibacterium acnes. Patients undergoing revision arthroplasty were included over a 2-year period (from 2012 up to 2014) in two French reference centers in compliance with IRB and French regulations. PJI cases were defined microbiologically (≥2 intraoperative samples yielding the same microorganism) for confrontation of microbiological and immunoassay data. 455 patients were eligible for study analyses. 149 patients (32.7%) were found to be infected. Among the most frequent infecting species recovered were S. aureus (30%), S. epidermidis (26%), P. acnes (9%), S. lugdunensis (6%), and S. agalactiae (4%). The sensitivity and specificity values of the test were, respectively, 75.9% (63/83) and 82.2% (180/219) for staphylococci (S. aureus, S. epidermidis, S. lugdunensis), 38.5% (5/13) and 81.9% (190/232) for P. acnes, and 66.7% (4/6) and 92.4% (208/225) for S. agalactiae. Interestingly, all cases (9/9) involving S. lugdunensis were detected by the test and the sensitivity for S. epidermidis reached 79.4% in patients more than three months after joint replacement. In a similar fashion, 89.5% (17/19) in the subpopulation with elevated inflammatory markers (ESR>30 and CRP>10). The assay correctly identified 67% of the microbiologically positive patients that were negative by ESR or CRP screening. This novel multiplex serological test allows the rapid and non-invasive diagnosis of the most frequent PJI pathogens, showing a good correlation with microbiological culture. and appears to be a new promising tool in the management of PJI, adding sensitivity to the current serological assays and enhancing the management of patients with pauci-inflammatory PJI.
