Aim. Tedizolid is an oxazolidinone antibiotic that: (i) is recommended at the dose of 200 once daily in patients with skin and soft tissue infection; (ii) seems to have a better long-term hematological and neurological safety profile in comparison with linezolid; (iii) remains active on multidrug-resistant (MDR) Gram-positive pathogens. Consequently, it might represent an option as suppressive antimicrobial treatment (SAT) in patients with complex implant-associated bone and joint infection (BJI) due to MDR Gram-positive pathogens. Method. We performed a cohort study (2017–2020) to evaluate the long-term safety of tedizolid (200mg qd) as SAT in patients with implant-associated BJI. In all cases, the use of tedizolid was validated as the last oral treatment option during multidisciplinar meetings in a reference center for the management of BJI. Serious adverse events, any reason for discontinuation, and standard biological data, were prospectively collected. Results. Seventeen patients (13 males; median age 73 years) received tedizolid as SAT for late complex prosthetic-joint infections (n=16) or osteosynthesis (n=1). Pathogens were MDR coagulase negative staphylococci (16 patients), Corynebacterium striatrum (2 patients), Enterococcus faecium (1 patient) and/or S. aureus (1 patient). Tedizolid was always started after a primary treatment (median duration of intravenous 47 days; followed by linezolid in 12 patients including 9 who experienced linezolid-induced serious adverse event) that followed a surgery, mainly debridement and implant retention (13 patients). Median duration of tedizolid was 6 months (min, 1 month; max, 31 months). The only reason for discontinuation was a failure of the conservative strategy that occurred in four patients (17%) during the follow-up. No patients developed a serious adverse event, or a discontinuation of tedizolid due to an adverse event. Anemia was observed in two patients, who had already other known cause of anemia (chronic leukemia and oesophageal varices); stable thrombopenia was observed in a cirrhotic patient (80 G/L, stable during the treatment course of 12 months); and a transient mild neutropenia (1.4 G/L) was observed in another patient (Figure). No neurological adverse event was observed. Conclusions. Tedizolid seems to be a safe option as SAT in patients with complex implantassociated BJI due MDR Gram-positive pathogens. For any tables or figures, please contact the authors directly

Aim. We aimed to assess the incidence and the outcome of Gram-negative prosthetic-joint infections (PJI) in 3 international tertiary hospital. Method. We included patients with Gram-negative PJI at Humanitas Clinical and Research Hospital (Milan, Italy), Centre Hospitalier Universitaire Vaudois (Lausanne, Switzerland) and Hospital Parc de Salut Mar (Barcelona, Spain) between 2014 and 2018 in a retrospective cohort. We described the treatment's success rate according to Gram-negative species and type of surgical procedure. Results. In the present cohort we have 780 PJI out of which 71 (9.1%) were caused by Gram-negative bacteria (polymicrobial infection 30%, Escherichia coli 25%, Pseudomonas aeruginosa 20%, Proteus spp. 4%, Klebsiella spp. 3%, Morganella morganii 3%, Enterobacter 3%, others 12%). Gram-negative PJI were more common in females (60%) than males (40%). Sixty percent had a hip infection, 40% a knee infection, the median age was 74 years and the median ASA score was 3. It was a chronic infection in 60% of the cases and an acute one in 40%. Two-step exchange was performed in 55%, débridement and retention (DAIR) in 30%, one-step exchange in 11% and implant removal without replacement in 4% of the patients. The overall treatment success rate was 89%. The success rate was better for two-step exchange (95%) compared to DAIR (81%) and one-step exchange (87%) (p=0.068). The median antibiotic duration was 68 days and ciprofloxacin was used in 70% of the cured patients versus in 88% of the failures (p=0.388). Infections caused by Escherichia coli were associated with a lower success rate (83%) especially compared to Pseudomonas aeruginosa (93%) and polymicrobial infections (90%) (p=0.358). Finally, the success rate was better in knee PJI compared to hip PJI (97% versus 83%, p=0.121) and in females compared to males (93% versus 82%, p=0.121). Conclusions. The treatment's success of Gram-negative PJI is comparable to reported rates for all bacteria. However, our results suggest that surgical management with two-step exchange might be useful in selected patients’ groups such as those with Escherichia coli PJI. Moreover, ciprofloxacin use seems not to improve cure rate

Aim. There is a constant increase of total joint arthroplasties to improve the quality of life of an aging population. Prosthetic-joint infections are rare, with an incidence of 1–2%, but they represent serious complications in terms of morbidity and mortality. Different therapeutic options exist, but the role of the surgeon's experience has never been investigated. The aim of this retrospective study is to assess the infection eradication success rate depending on the involvement of a septic surgeon. Method. Patients having a prosthetic-joint infection at Lausanne University Hospital (Switzerland) between 2006 and 2018 were included. The success rate depending on type of surgeon (septic vs non-septic) and type of surgical procedure was analyzed. Results. 444 patients (61% hips, 37% knees) were identified with a median age of 70 years. The overall success rate was 83% for septic surgeons compared to 61% for non-septic surgeons (p < 0.05). The effect of the surgeon was predominant in debridement with retention of the prosthesis where the experience could improve the success rate from 43% (non-septic) to 75% (septic) (p < 0.05). Conclusions. The involvement of a septic surgeon is associated with a significantly higher success rate, suggesting surgical experience is an important factor in treating prosthetic-joint infections

Aim. This study aims to describe our department experience with single stage revision (SSR) for chronic prosthetic-joint infection (PJI) after total hip arthroplasty (THA) between 2005 and 2014 and to analyze success rates and morbidity results of patients submitted to SSR for infected THA according to pathogen. Method. We retrospectively reviewed our 10 years of results (2005–2014) of patients submitted to SSR of the hip combined with IV and oral antibiotic therapy for treatment of chronic PJI (at least 4 weeks of symptoms), with a minimum follow-up of four years (n=26). Patients were characterized for demographic data, comorbidities, identified germ and antibiotic therapy applied (empiric and/or targeted). Outcomes analyzed were re-intervention rate (infection-related or aseptic), success rate (clinical and laboratory assessment), length of stay, morbidity and mortality outcomes. Results. In this period, 26 single-stage revisions for chronic PJI of the hip were performed. Patients average age was 72 years (range 44–82). Ten patients were women. The average time of follow up was 69 months (range 4 to 12 years). The most commonly isolated bacteria were coagulase-negative Staphylococci (30%), methicillin-resistant Staphylococcus aureus (MRSA) (18%) and methicillin-sensitive Staphylococcus aureus (15%). It wasn't possible to identify the germ in 19% of the patients and other 23% were polymicrobial. Targeted antibiotic therapy was administered to 73% of patients and the most used targeted antibiotics were Vancomycin (53%), Linezolid (32%) and Rifampicin (21%). Mean length of stay was 25 days. In the follow-up period, 9 patients (35%) required a re-intervention for infection relapse. Two patients (8%) needed surgery because of persistent instability. During the follow-up period, the infection-free survival was 65% (33% for MRSA; 82% for coagulase-negative Staphylococci) and the surgery-free survival was 62%. Six patients (23%) died during the follow-up, all due to other medical conditions not related to hip infection. Conclusions. Our experience suggests that SSR is associated with good outcomes and low re-intervention rate, except in the case of infection due to MRSA. In this last group, the results were significantly poorer, what leads to suggest that a two-stage revision may be a better option. The potential advantages of a SSR include good rates of infection eradication, a decrease in surgical morbidity and mortality as well as a decrease in healthcare and global economic costs. As such, a one-stage aggressive surgical attitude in addition to targeted antibiotherapy seems to be a suitable solution in selected patients

Aim. There is a constant increase of total joint arthroplasties to improve the quality of life of an aging population. Prosthetic-joint infections are rare, with an incidence of 1–2%, but they represent serious complications in terms of morbidity and mortality. Different therapeutic options exist, but their management is still poorly standardized because of the lack of data from randomized trials. The aim of this retrospective study is to assess the infection eradication success rate, over the last ten years, using different patient adapted treatment options. Method. Patients having a prosthetic-joint infection at Lausanne University Hospital (Switzerland) between 2006 and 2016 were included. The success rate depending on age, type of prosthesis, type of infection and type of surgical procedure was analyzed. Results. 444 patients (61% hips, 37% knees) were identified with a median age of 70 years. The success rate was 93% for two-stage exchange, 78% for one-stage exchange and 75% for debridement with retention of the prosthesis. The failure rate was higher for knee prosthetic-joint infections (27%) than hip infections (13%). Furthermore, chronic and in elderly prosthetic-joint infections seemed to have a worse prognosis. Conclusions. The infection eradication depends on age, type of prosthesis, type of infection and type of surgical procedure, with three times less failure in two-stage exchange surgery

Aim. There is a constant increase of joint arthroplasties to improve the quality of life of an aging population. Prosthetic-joint infections are rare, with an incidence of 1–2%, but they represent serious complications in terms of morbidity and mortality. The mortality was known to be approaching 8% in the elderly. The aim of this retrospective study is to reassess the two-year mortality rate over the last ten years. Method. Patients having a prosthetic joint infection at Lausanne University Hospital (Switzerland) between 2006 and 2016 were included. The two-year mortality rate depending on sex, age, type of infection and type of surgical therapy was measured. Results. 444 patients (61% hips, 37% knees) were identified with a median age of 70 years. The two-year mortality rate was 5%. There was no difference between hip and knee prosthesis but the mortality was higher for men (6%) than women (4%). The rate has not changed over the last ten years. However, the mortality rate is more than doubling (12%) for patients over eighty years old. Furthermore, chronic prosthetic-joint infections seem to have a higher mortality rate (7%) than acute ones (4%). Finally, patients treated with a one-stage or two-stage exchange seem to have a lower mortality rate (<1%) than the ones treated with debridement and retention (11%). Conclusion. The mortality seems to be less than thought before and depends on sex, age, type of infection and type of surgical therapy

The diagnosis of prosthetic-joint infection (PJI) is challenging, as bacteria adhere on implant and form biofilm. Therefore, current diagnostic methods, such as preoperative culture of joint aspirate have limited sensitivity with false-negative results. Aim. To evaluate the performance of measurement synovial fluid (SF) D-lactate (as a pathogen-specific marker) for the diagnosis of PJI and estimate of treatment success. Method. 224 patients undergoing removal knee or hip prosthesis were included in the study between January 2015 and March 2017. 173 patients of this group had aseptic loosening of prosthesis and 87 were diagnosed with PJI. Prior to surgery, synovial fluid routine culture, D-lactate test, leukocyte count and neutrophils (%) were performed for each patient. In order to evaluate a treatment success, the measurement of SF D-lactate before second two-stage exchange procedure (after treatment) was implemented in 30 patients. Diagnosis of PJI was established according to modified Zimmerli criteria. Results. Of 87 patients with infection of prosthetic joints, 61 (70%) had positive synovial fluid cultures, including Staphylococcus spp. (70%), Streptococcus spp. (10%), Enterococcus spp. (6%), Anaerobes (6%), Enterobacteriacae (4%), P. aeruginosa (2%), C. parapsilosis (2%). There was no significant difference in SF D-lactate levels due to different bacterial strains. The optimal D-lactate cut off was 1,2 mmol/l (sensitivity = 98%, specificity = 84%, PPV = 79%, NPV = 98%, AUC 0,99). Concentration of SF D-lactate was significantly higher in patients with PJI compared to aseptic loosening of prosthesis (median (range)) 2.33 (0.99–3.36) vs 0.77 (0.01–2.4), p<0.0001.D-lactate has better sensitivity for diagnosis of PJI (98%), compared to leukocytes (80%) and neutrophils % (89%), p<0.0001). The concentration of D-lactate decreased below cut off within four weeks after revision surgery (after treatment) in all patients except of three, showing relapse of infection (p<0.0001). Conclusions. The measurement of synovial fluid D-lactate demonstrated high analytical performance in the diagnosis of PJI, it is a reliable pathogen specific marker. D-lactate has the best sensitivity as independent diagnostic method and could be implemented for the evaluation of treatment success

In spite of its incidence decreasing to 1% nowadays, prosthesis-related infections remain a research, diagnostic, therapeutic and cost-related problem. Early diagnosis, selection of an appropriate surgical strategy, accurate identification of the responsible microorganisms and construction of an appropriate antibiotic regimen are essential elements of any management strategy. Our study aim was firstly to compare the diagnostic accuracy of conventional periprosthetic tissue culture and culture of fluid derived from vortexing and bath sonication of the explanted hardware and secondly to investigate the role of possible metabolic factors affecting the sensitivity of the sonication method. We investigated 70 patients undergoing revision hip or knee arthroplasty because of loosening of the prostheses, at our institution, between October 2011 and November 2013. Patients’ medical history and demographic characteristics were recorded. We compared the culture of samples obtained by sonication of explanted hip and knee prostheses with conventional culture of periprosthetic tissue for the microbiological diagnosis of prosthetic-joint infection. Infectious Diseases Society of America (IDSA) Guidelines were used for the definition of prosthetic-joint infection. Thirty-two patients had septic loosening and 38 aseptic loosening (48 hip prostheses and 22 knee prostheses). The sensitivity of sonication fluid culture was 81.25% and the sensitivity of conventional tissue cultures was 56.25% (p-value = 0.043). The sensitivity of the sonication method was statistically higher in obese, diabetic patients, with age above 60, in uncemented arthroplasties and in arthroplasties because of primary osteoarthritis (p-values < 0.05). The sonication method represents a reliable test for the diagnosis of prosthetic – joint infections with a greater sensitivity than the conventional periprosthetic tissue cultures, especially in obese, diabetic patients, with age above 60, in uncemented arthroplasties and in arthroplasties because of primary osteoarthritis

The costs related to the treatment of infected total joint arthroplasties represent an ever groving burden to the society. Different patient-adapted therapeutic options like débridement and retention, 1- or 2-step exchange can be used. If a 2-step exchange is used we have to consider short (2–4 weeks) or long (>4–6 weeks) interval treatment. The Swiss DRG (Diagnose related Groups) determines the reimboursement the hopsital receives for the treatment of an infected total arthroplasty. The review assesses the cost-effectiveness of hospitalisation practices linked to surgical treatment in the two-stage exchange of a prosthetic-joint infection. The aim of this retrospectiv study is to compare the economical impact between a short (2 to 4 weeks) versus a long (6 weeks and above) interval during a two-satge procedure to determine the financial impact. Retrospectiv study of the patients with a two-stage procedure for a hip or knee prosthetic joint infection at CHUV hospital Lausanne (Switzerland) between 2012 and 2013. The review analyses the correlation between the interval length and the length of the hospital stay as well as with the costs and revenues per hospital stay. In average there is a loss of 40′000 Euro per hospitalisation for the treatment of prosthetic joint infection. Revenues never cover all the costs, even with a short interval procedure. This economical loss increases with the length of the hospital stay if a long-term intervall is choosen. The review explores potential for improvement in reimbourement practices and hospitalisation practices in the current Swiss healthcare setting. There should be alternative setups to decrease the burden of medical costs by a) increase the reimboursment for the treatment of infected total joints or by b) splitting the hospital stay with partners (rapid transfer after first operation from center hospital to level 2 hospital and retransfer for second operation to center) in order to increase revenues

We have designed a prospective study to evaluate the usefulness of prolonged incubation of cultures from sonicated orthopaedic implants. During the study period 124 implants from 113 patients were processed (22 osteosynthetic implants, 46 hip prostheses, 54 knee prostheses, and two shoulder prostheses). Of these, 70 patients had clinical infection; 32 had received antibiotics at least seven days before removal of the implant. A total of 54 patients had sonicated samples that produced positive cultures (including four patients without infection). All of them were positive in the first seven days of incubation. No differences were found regarding previous antibiotic treatment when analysing colony counts or days of incubation in the case of a positive result. In our experience, extending incubation of the samples to 14 days does not add more positive results for sonicated orthopaedic implants (hip and knee prosthesis and osteosynthesis implants) compared with a conventional seven-day incubation period.

Cite this article: Bone Joint J 2013;95-B:1001–6.

Implants are highly susceptible to infection [. 1. ]. The infection rate is 0.5–2% after hip or knee arthroplasty [. 2. ]. Periprosthetic joint infections are hard to eradicate. Until recently, two-stage exchange or life-long antibiotic suppression therapy has been the rule. However, novel treatment concepts evolved. Whereas no controlled trials on the surgical management of prosthetic-joint associated infection are available, much is known about the optimal antimicrobial therapy. Modern treatment concepts are based on animal studies, in vitro data, observational studies and one single controlled trial comparing two different antimicrobial regimens in patients with orthopaedic device-associated infections [. 2. ]. The tissue-cage guinea pig model is especially suitable to analyse the role of antibiotics in device-related infections [. 3. ]. In this model, different aspects of implant-associated infections have been studied, namely. host-defense mechanisms around implants [. 1. ],. risk of hematogeneous infection of extravascular devices [. 4. ],. efficacy of prevention or antibiotic treatment [. 5. –. 12. ],. correlation between efficacy of treatment in vivo and in vitro [. 11. ,. 12. ], and the role of biofilm formation on the activity of antibiotics [. 11. ]. Taken together, these experiments showed that an agent acting on slow-growing and adhering microorganism is needed to eradicate device-associated infection. This requirement is only fulfilled by rifamycins in staphylococcal infection and by fluoroquinolones in infections caused by gram-negative bacilli [. 5. –. 12. ]. We could show that even new drugs against methicillin-resistant staphylococci (MRSA), such as linezolid and daptomycin, were not able to eradicate experimental foreign-body infections, when used as single agents. In contrast, in combination with rifampin linezolid cured 60%, and daptomycin 67% of the implant-associated MRSA-infections [. 9. ,. 10. ]. Based on these in vitro and animal data, observational studies were performed in patients with staphylococcal infections associated to orthopedic devices. We developed an algorithm allowing to choose the optimal therapeutic option for each patient [. 2. ]. This algorithm has been validated in cohort studies [. 13. ,. 14. ]. Finally, in a randomized double-blind controlled trial, the benefit of a rifampin-quinolone combination as compared to quinolone monotherapy has been proven in patients with acute orthopedic implant associated staphylococcal infection undergoing debridement with retention [. 15. ]. In conclusion, the favorable role of rifampin has been proven in vitro, in animals and in human studies. Also the newest antistaphylococcal agents must be given in combination with rifampin in order to eliminate infection without removal of the device

Background: The presence of bacteria forming biofilms or prior antimicrobial use has been shown to reduce the sensitivity of the standard technique (PT cultures) in patients with infection of orthopedic implants. Culturing fluid resulting from sonication (FRS) of prosthesis could improve the microbiologic diagnosis. Objective: To analyze the diagnostic validity of culturing FRS of different orthopedic implants and PT culture. Methods: Between Jan 2007 and Apr 2008, patients undergoing knee or hip prosthesis removal, and those with ostheosyntesis or spinal instrumentation removal, were prospectively included (44 hip prosthesis, 63 knee prosthesis, 91 osteosynthesis and 14 spinal instrumentations). 5 PT specimens were collected for culture. Removed implants were sonicated during 5 min. (40Hz). Both, PT and FRS, were inoculated in aerobic agar (Chocolate Polyvitex), anaerobic agar (Schaedler + 5% blood) and in thioglycolat, for 7 days. Positive culture cut-off was defined as growing of > 5 CFU. Clinical diagnosis of prosthetic-joint infection was made as commonly accepted. Previous antimicrobial therapy was assessed. Diagnostic validity was calculated for both culturing methods. Sensitivity of methods was compared by Chi-square test (SPSS 15.0). Results: 212 cases were included. Diagnostic of infection was made in 17 hip prosthesis (THA), 20 knee prosthesis (TKA), 24 osteosynthesis (OS) and 6 spinal fusions (SI). Tissue culture was positive in 9 THA, 11 TKA 18 OS and 4 SI. Sonication culture was positive in 14 THA, 18TKA, 23 Os and 6 SI. Tissue culture: Sensibility: THA53%, TKA 55%, OS 75% and SI 66%. Specificity: THA 96%, TKA 100%, OS 96%, SI 100%. Sonications: Sensibility: THA 82%, TKA 90%, OS 95% and SI 100%. Specificity: THA 96%, TKA 100%, OS 92%, SI 100%. Statistical differences favoring sonication were found in sensitivity in knee arthroplasty and osteosynthesis implants. 6 patients received antibiotics for > 7 days before implant was removed. Sonication culture was positive in 4 of them whereas only one standard culture yielded positive. Conclusions: FRS cultures are more sensitive than PT cultures. Sensitivity of the method depends on which device is evaluated. Sonication also improves sensitivity of culture after preoperative antimicrobial therapy