At our tertiary orthopaedic centre, mycobacterial cultures are routinely performed on bone and joint samples sent for bacterial culture. We have previously described the prevalence Samples taken during a single procedure were pooled in one BACTEC MGIT culture. From laboratory records, we ascertained the number of mycobacterial cultures performed, the number positive for MTBC or NTM, and characteristics of individuals from whom mycobacteria were isolated. We collected the same data from 100 individuals with negative mycobacterial cultures. Results presented here are from interim analysis.Aim
Methods
Deep infection following endoprosthetic replacement (EPR) of long bones is a devastating complication occurring in 15% of musculoskeletal tumour patients. The recently published PARITY Trial demonstrated that extending antibiotic prophylaxis from 24 hours to 5 days does not reduce infection rates. However, questions remain about the optimal antibiotic choice and dose. A 23-question multiple-choice questionnaire was designed and piloted through an iterative feedback process until the final version was agreed by all authors. Open and closed-ended questions were used to gather information on practice and Likert-type scale responses were used to grade responses to ascertain surgeon perceptions and preferences. The online survey was sent to all surgeon delegates of the 34th Annual Meeting of the European Musculo-Skeletal Oncology Society in London in October 2022.Aim
Method
Dalbavancin is a lipoglycopeptide with a half-life of 14 days (range 6.1 to 18.4), significantly longer than other antimicrobials, which avoids the need for daily antibiotic dosing. This multi-centre observational study aims to describe the use of dalbavancin to facilitate discharge in treating bone and joint infections. All adult patients treated with dalbavancin from January 2017 to September 2022 in four UK bone infection units were included. Data collected through a standardised data collection form included: Clinical and microbiological characteristics. Hospital length of stay. Complications. Patient suitability for hypothetical treatment options, such as Outpatient Parenteral Antibiotic Team (OPAT) Clinical outcome. Treatment-related costs were calculated for dalbavancin and the preferred hypothetical treatment option that would have been administered for the same duration. The costs were subtracted to calculate the cost difference. Clinical success was defined as the absence of definite failure in accordance with the OVIVA Trial protocol.Aim
Method
Mega-endoprosthesis over the last two decades have played a significant role in management of non-neoplastic cases for limb salvage for a variety of indications involving bone loss, infection, fracture and failed revision surgery. This is a retrospective case control study comparing outcomes of Mega-Endoprosthesis (MEP) in non-neoplastic cases with periprosthetic joint infections (PJI), with previous history of PJI and aseptic revision. Failure was defined as persistence/recurrence of infection, all cause revision, and antibiotic suppression during the follow up period. Secondary aims were identification of causative organisms, resistance profile and causative factors for revision surgery. A total of 122 patients undergoing 133 MEPs were identified between January 2012 and December 2020. 60 procedures were categorised as group 1 (infection; 50%), 20 as group 2 (previous history of infection; 16.7%), and 53 controls (no infection; 44.2%). Mean age of the cohort was 70.97 years (37.16–94.17), with a mean follow-up of 44.5 months (0.2–179) including patients lost to follow up.Aim
Method
There is a lack of data supporting the use of doxycycline as a single agent after removing infected orthopaedic metalwork. We evaluated the efficacy and safety of doxycycline compared with other single antibiotic regimens used at our specialist orthopaedic hospital. A retrospective observational study including all adult patients diagnosed with an orthopaedic metalwork infection due to staphylococci. All patients were managed with the removal of metalwork, and multiple intraoperative samples were sent for culture, followed by the administration of at least four weeks of oral antibiotics. Antibiotic selection was on the recommendation of an infection consultant. Infection outcome was assessed as the proportion of patients meeting the OVIVA Trial definition of definite failure at follow-up. The probability of definite failure for doxycycline and the alternatives group was estimated using the Kaplan-Meier survival method. All adverse drug reactions (ADR) during treatment were analysed.Aim
Methods
The primary aim of this study was to evaluate the outcomes of fungal knee periprosthetic joint infection following knee arthroplasty. The secondary aim was to evaluate risk factors for acquiring a fungal PJI. This was a retrospective analysis of patients presenting with a confirmed fungal PJI of the knee in two tertiary centres. There were a total of 45 cases. Isolated fungal infections along with mixed bacterial and fungal infections were included. Mean follow up was 40 months (range 3–118).Abstract
Aims
Patients and Methods
Management of bone and joint infection can be technically complex and often requires a prolonged course of antibiotics. Traditionally, bone and joint infection management utilises nurse-led outpatient parenteral antibiotic therapy (OPAT) where adherence is unlikely to be an issue. However, with increasing evidence in favour of oral therapy, the question of adherence merits further consideration. We describe the adherence of both oral (PO) and self-administered intravenous (IV) antibiotics in the treatment of bone and joint infection using paper questionnaires (8-item Modified Morisky Adherence Score (MMAS)) and, in a subset of participants, electronic pill containers (Medication Event Monitoring Systems*). All eligible participants enrolled in the OVIVA trial (2010–2015) were randomised to six weeks of either PO or IV antibiotic treatment arms. Self-administering patients were followed up with questionnaires at day 14 and 42. A subset of PO participants was also given the medication event monitoring system* in order to validate the adherence questionnaires. The results were correlated with treatment failures at one-year follow-up.Aim
Method
Current standard of care in the management of bone and joint infection commonly includes a 4–6 week course of intravenous (IV) antibiotics but there is little evidence to suggest that oral antibiotic therapy results in worse outcomes. The primary objective was to determine whether oral antibiotics are non-inferior to IV antibiotics in this setting. This was a parallel group, randomised (1:1), open label, non-inferiority trial across twenty-six NHS hospitals in the United Kingdom. Eligible patients were adults with a clinical diagnosis of bone, joint or orthopaedic metalware-associated infection who would ordinarily receive at least six weeks of antibiotics and who had received ≤7 days of IV therapy from the date of definitive surgery (or the start of planned curative treatment in patients managed non-operatively). Participants were randomised to receive either oral or IV antibiotics for the first 6 weeks of therapy. Follow-on oral therapy was permitted in either arm. The primary outcome was the proportion of participants experiencing definitive treatment failure within one year of randomisation. The non-inferiority margin was set at 7.5%.Aim
Method
Fungi are a rare and devastating cause of Periprosthetic Joint Infection (PJI). Diagnosis and treatment is a challenge as there are currently no specific guidelines. A recently published review identified 75 case reports of fungal PJI. The aim is to describe our experience of treating fungal PJI since 2011 within the Bone Infection Unit at our institution.Introduction
Aim
Diagnosing Orthopaedic infection is limited by the sensitivity of culture methods. Next generation sequencing (NGS) offers an alternative approach for detection of microorganisms from clinical specimens. However, the low ratio of pathogen DNA to human DNA often inhibits detection of microorganisms from specimens. Depletion of human DNA may enhance the detection of microbial DNA1. Our aim was to compare four DNA extraction methods for the recovery of microbial DNA from orthopaedic samples for NGS. Simulated samples; pooled culture negative sample matrix was spiked with known concentrations of microorganisms, each panel consisting of 7 samples. Broth culture was performed on simulated samples for comparison with NGS DNA Extraction; total nucleic acid extraction was performed on an automated extraction platform Detection of human and microbial DNA; human endogenous (HE) gene rtPCRAim
Method
Beadmill processing combined with automated blood culture bottle methods (BACTEC™) has a greater sensitivity and specificity, and a shorter time to positivity compared with primary plates (PP) for prosthetic joint infection (PJI) diagnosis but the clinical impact of Bactec on antimicrobial therapy has not yet been evaluated. We compared time-to-positivity of Columbia agar with horse blood plates (BA) and chocolatized horse blood plates (CHOC) versus anaerobic (ANA) and aerobic blood culture bottles (02) in patients with PJI. We compared the contributions of the two methods to the commencement of effective and targeted antimicrobial therapy. Retrospective observational study from June 2013 to March 2014. Inclusion criteria were confirmed PJI (IDSA criteria) with at least 2 perioperative samples. After beadmill processing BA and CHOC plates were incubated for 2 days and discarded if negative, BactecTM bottles were incubated for 14 days and sub-cultured if positive. MALDI-TOF (Microflex, Brucker) was used for identification and all isolates had sensitivities performed (Phoenix, BD). Standard empirical antibiotic treatment was teicoplanin, piperacillin/tazobactam and amikacin. We defined time to switch as difference between date of sample collection and date of commencing targeted or effective therapy; prior antibiotic therapy was defined as the use of antibiotics within 14 days before samples collection. Fifty cases were identified during the study period. 330 microbiological isolates were included: 24 (7.3%) were considered contaminants; 153 isolates (50.0%) were detected both from BactecTM and PP; 152 (49.7%) from BactecTM only; 1 isolate (0.3%) from PP only. 17 (34%) diagnoses of PJI was made exclusively by BactecTM. The majority of isolates on BA and CHOC plates grew in the first 24 hours (81.2% and 77.5% respectively). 293/305 isolates from BactecTM (96.1%) grew in the first 2 days. Antibiograms were available after 2.5 days from PP versus 4 days from BACTEC (p<0.0001). When we compared time to switch from empiric to targeted therapy, no difference was seen between patients with positive BACTEC cultures only (median 4 days, range 2–15) versus patients with positive PP cultures, (median 5 days, range 2–9) (p=0.984). Where organisms were resistant to empirical therapy, PP results did not contribute to switching to effective therapy. Prior antibiotic therapy had no impact on time-to-positivity for both methods (R=−0.005, p=0.936). Compared to BACTEC cultures for the diagnosis of PJIs, primary plate cultures did not provide additional diagnostic information and did not significantly reduce the time to effective or targeted antimicrobial therapy.
