Aim. Diagnosing Orthopaedic infection is limited by the sensitivity of culture methods.
Surgical management of PJI remains challenging with patients failing treatment despite the best efforts. An important question is whether these later failures reflect reinfection or the persistence of infection. Proponents of reinfection believe hosts are vulnerable to developing infection and new organisms emerge. The alternative hypothesis is that later failure is a result of an organism that was present in the joint but was not picked up by initial culture or was not a pathogen initially but became so under antibiotic pressure. This multicenter study explores the above dilemma. Utilizing next-generation sequencing (NGS), we hypothesize that failures after two stage exchange arthroplasty can be caused by an organism that was present at the time of initial surgery but not isolated by culture. This prospective study involving 15 institutions collected samples from 635 revision total hip (n=310) and knee (n=325) arthroplasties. Synovial fluid, tissue and swabs were obtained intraoperatively for NGS analysis. Patients were classified per 2018 Consensus definition of PJI. Treatment failure was defined as reoperation for infection that yielded positive cultures, during minimum 1-year follow-up. Concordance of the infecting pathogen cultured at failure with NGS analysis at initial revision was determined.Introduction
Methods
Identification of modalities and procedures to improve the differential diagnosis of septic and aseptic cases in patients with joint-related pain after total hip or knee alloplasty (THA/TKA). A prospective cohort of 147 patients presenting with problems related to previous THA or TKA was included and subjected to a comprehensive diagnostic algorithm. The standard diagnostics were supplemented with novel or improved methods for sampling of clinical specimens, sonication of retrieved implant parts, prolonged and effective culture of microorganisms, and dedicated clinical samples for molecular biological detection and identification of microorganisms. Furthermore, comprehensive pain investigations and nuclear imaging were employed. For each case the clinical management was decided upon in a clinical conference with participation of clinical microbiologist, orthopedics and experts in nuclear imaging. The clinical management of patients was blinded against the molecular biological detection of microorganisms. Patients grouped as follows: 69 aseptic, 19 acute septic, 19 chronic septic, 40 pain/unresolved. Sonication of retrieved implant parts resulted in detection of biofilm not detected by standard specimens, i.e. joint fluid and periprosthetic tissue biopsies.
Aims. Current diagnostic tools are not always able to effectively identify periprosthetic joint infections (PJIs). Recent studies suggest that circulating microRNAs (miRNAs) undergo changes under pathological conditions such as infection. The aim of this study was to analyze miRNA expression in hip arthroplasty PJI patients. Methods. This was a prospective pilot study, including 24 patients divided into three groups, with eight patients each undergoing revision of their hip arthroplasty due to aseptic reasons, and low- and high-grade PJI, respectively. The number of intraoperative samples and the incidence of positive cultures were recorded for each patient. Additionally, venous blood samples and periarticular tissue samples were collected from each patient to determine miRNA expressions between the groups. MiRNA screening was performed by small RNA-sequencing using the miRNA
Hip resurfacing may be a useful surgical procedure when patient selection is correct and only implants with superior performance are used. In order to establish a body of evidence in relation to hip resurfacing, pseudotumour formation and its genetic predisposition, we performed a case-control study investigating the role of HLA genotype in the development of pseudotumour around MoM hip resurfacings. All metal-on-metal (MoM) hip resurfacings performed in the history of the institution were assessed. A total of 392 hip resurfacings were performed by 12 surgeons between February 1st 2005 and October 31st 2007. In all cases, pseudotumour was confirmed in the preoperative setting on Metal Artefact Reduction Sequencing (MARS) MRI. Controls were matched by implant (ASR or BHR) and absence of pseudotumour was confirmed on MRI. Blood samples from all cases and controls underwent genetic analysis using
Aim. Periprosthetic joint infection is an increasing reason for revision surgery. Tissue cultures are a standard (std.) diagnostic procedure but may be hindered by bacteria that are difficult to cultivate. The use of dithiothreitol (DTT) to detach the formed biofilm has been proposed to improve the diagnostic security. The aim was to compare the diagnosis results using the microDTTect device with the routine PJI diagnostics and
Summary Statement. Using the latest
Introduction. Recent focus has shifted towards the utilization of deoxyribonucleic acid (DNA) sequencing modalities in periprosthetic joint infection (PJI) diagnosis and organism identification. The purpose of this study was to compare the diagnostic accuracy of
Introduction. Recent focus has queried whether of deoxyribonucleic acid (DNA) sequencing modalities of bacterial DNA found in periarticular fluid and tissues will improve in periprosthetic joint infection (PJI) diagnosis and organism identification diagnostic accuracy for periprosthetic joint infection The purpose of this study was to compare the diagnostic accuracy of
Introduction. We aimed to identify genes associated with the development of ALVAL at relatively low levels of wear. Methods. At our unit all patients undergoing revision of a MoM hip prosthesis have periprosthetic tissue samples graded for ALVAL. Explants undergo volumetric wear testing of the bearing and taper surfaces. We identified patients with moderate/severe ALVAL who had been exposed to lower than the median wear rate of all recorded patients who had developed ALVAL (<3mm. 3. /year). This was termed the “ALVAL” group. We then identified all patients whose tissues had shown no signs of ALVAL. The patients in the two groups were sent buccal DNA collection kits. DNA was examined using
Background. Recent reports demonstrate that
Introduction. The prevalence of symptomatic osteoarthritis (OA) in the knee is 11–11% compared to 3.4–4.4% in the ankle. In addition to this, 70% of ankle arthritis is post-traumatic while the vast majority of knee arthritis is primary OA. Several reports have previously implicated biochemical differences in extracellular matrix composition between these joint cartilages; however, it is unknown whether there is an inherent difference in their transcriptome and how this might affect their respective functionality under load, inflammatory environment etc. Therefore, we have analysed the transcriptome of ankle and knee cartilage chondrocytes to determine whether this could account for the lower prevalence and altered aetiology of ankle OA. Methods. Human full-depth articular cartilage was taken from the talar domes (n=5) and the femoral condyles (n=5) following surgical amputation. RNA was extracted and
Introduction.
Recent evidence suggests that the microbial community, its spatial distribution and activity play an important role in the prolongation of treatment and healing of chronic infections. Standard bacterial cultures often underestimate the microbial diversity present in chronic infections. This lack of growth is often due to a combination of inadequate growth conditions, prior usage of antibiotics and presence of slow-growing, fastidious, anaerobic or unculturable bacteria living in biofilms. Thus, diagnosis of chronic infections is challenged by lack of appropriate sampling strategies and by limitations in microbiological testing methods. The purpose of this study was to improve sampling and diagnosis of prosthetic joint infections (PJI) and chronic wounds, especially considering the biofilm issue. Systematic sampling, sonication of prosthesis and extended culture were applied on patients with chronic wounds and patients with suspected PJIs. Optimized DNA extraction, quantitative PCR, cloning,
Hip resurfacing remains a potentially valuable surgical procedure for appropriately-selected patients with optimised implant choices. However, concern regarding high early failure rates continues to undermine confidence in use. A large contributor to failure is adverse local tissue reactions around metal-on-metal (MoM) bearing surfaces. Such phenomena have been well-explored around MoM total hip arthroplasties, but comparable data in equivalent hip resurfacing procedures is lacking. In order to define genetic predisposition, we performed a case-control study investigating the role of human leucocyte antigen (HLA) genotype in the development of pseudotumours around MoM hip resurfacings. A matched case-control study was performed using the prospectively-collected database at the host institution. In all, 16 MoM hip resurfacing 'cases' were identified as having symptomatic periprosthetic pseudotumours on preoperative metal artefact reduction sequence (MARS) MRI, and were subsequently histologically confirmed as high-grade aseptic lymphocyte-dominated vasculitis-associated lesions (ALVALs) at revision surgery. ‘Controls’ were matched by implant type in the absence of evidence of pseudotumour. Blood samples from all cases and controls were collected prospectively for high resolution genetic a nalysis targeting 11 separate HLA loci. Statistical significance was set at 0.10 a priori to determine the association between HLA genotype and pseudotumour formation, given the small sample size.Aims
Methods