Aims

Bacteriophages infect, replicate inside bacteria, and are released from the host through lysis. Here, we evaluate the effects of repetitive doses of the Staphylococcus aureus phage 191219 and gentamicin against haematogenous and early-stage biofilm implant-related infections in Galleria mellonella.

Aims

Serum inflammatory parameters are widely used to aid in diagnosing a periprosthetic joint infection (PJI). Due to their limited performances in the literature, novel and more accurate biomarkers are needed. Serum albumin-to-globulin ratio (AGR) and serum CRP-to-albumin ratio (CAR) have previously been proposed as potential new parameters, but results were mixed. The aim of this study was to assess the diagnostic accuracy of AGR and CAR in diagnosing PJI and to compare them to the established and widely used marker CRP.

Aims

The number of revision arthroplasties being performed in the elderly is expected to rise, including revision for infection. The primary aim of this study was to measure the treatment success rate for octogenarians undergoing revision total hip arthroplasty (THA) for periprosthetic joint infection (PJI) compared to a younger cohort. Secondary outcomes were complications and mortality.

Aims

This study aimed to evaluate the BioFire Joint Infection (JI) Panel in cases of hip and knee periprosthetic joint infection (PJI) where conventional microbiology is unclear, and to assess its role as a complementary intraoperative diagnostic tool.

The June 2024 Knee Roundup³⁶⁰ looks at: The estimated lifetime risk of revision after primary knee arthroplasty influenced by age, sex, and indication; Should high-risk patients seek out care from high-volume surgeons?; Stability and fracture rates in medial unicondylar knee arthroplasties; Rethinking antibiotic prophylaxis for dental procedures post-arthroplasty; Evaluating DAIR: a viable alternative for acute periprosthetic joint infection; The characteristics and predictors of mortality in periprosthetic fractures around the knee; Patient health-related quality of life deteriorates significantly while waiting six to 12 months for total hip or knee arthroplasty; The importance of looking for diversity in knee implants.

Aims

Accurate diagnosis of chronic periprosthetic joint infection (PJI) presents a significant challenge for hip surgeons. Preoperative diagnosis is not always easy to establish, making the intraoperative decision-making process crucial in deciding between one- and two-stage revision total hip arthroplasty (THA). Calprotectin is a promising point-of-care novel biomarker that has displayed high accuracy in detecting PJI. We aimed to evaluate the utility of intraoperative calprotectin lateral flow immunoassay (LFI) in THA patients with suspected chronic PJI.

Aims

Periprosthetic joint infection (PJI) demonstrates the most feared complication after total joint replacement (TJR). The current work analyzes the demographic, comorbidity, and complication profiles of all patients who had in-hospital treatment due to PJI. Furthermore, it aims to evaluate the in-hospital mortality of patients with PJI and analyze possible risk factors in terms of secondary diagnosis, diagnostic procedures, and complications.

Aims

Metal particles detached from metal-on-metal hip prostheses (MoM-THA) have been shown to cause inflammation and destruction of tissues. To further explore this, we investigated the histopathology (aseptic lymphocyte-dominated vasculitis-associated lesions (ALVAL) score) and metal concentrations of the periprosthetic tissues obtained from patients who underwent revision knee arthroplasty. We also aimed to investigate whether accumulated metal debris was associated with ALVAL-type reactions in the synovium.

Aims

The benefit of a dual-mobility acetabular component (DMC) for primary total hip arthroplasties (THAs) is controversial. This study aimed to compare the dislocation and complication rates when using a DMC compared to single-mobility (SM) acetabular component in primary elective THA using data collected at a single centre, and compare the revision rates and survival outcomes in these two groups.

The February 2024 Research Roundup. 360. looks at: If you use a surgical helmet, you should seal your gown-glove interface; The use of iodophor-impregnated drapes in patients with iodine-related allergies: a case series and review of the literature; Location of the ovaries in children and efficacy of gonadal shielding in hip and pelvis radiography; Prehospital tranexamic acid administration does not improve outcomes in severe trauma patients; Silver-coated distal femur megaprosthesis in chronic infections with severe bone loss: a multicentre case series

Aims

This study aimed to evaluate the clinical application of the PJI-TNM classification for periprosthetic joint infection (PJI) by determining intraobserver and interobserver reliability. To facilitate its use in clinical practice, an educational app was subsequently developed and evaluated.

Aims

A higher failure rate has been reported in haematogenous periprosthetic joint infection (PJI) compared to non-haematogenous PJI. The reason for this difference is unknown. We investigated the outcome of haematogenous and non-haematogenous PJI to analyze the risk factors for failure in both groups of patients.

Aims

Fungal periprosthetic joint infections (PJIs) are rare, but their diagnosis and treatment are highly challenging. The purpose of this study was to investigate the clinical outcomes of patients with fungal PJIs treated with two-stage exchange knee arthroplasty combined with prolonged antifungal therapy.

Aim. The objective of this systematic review is to evaluate the current evidence for or against this up-and-coming treatment modality. Method. A comprehensive literature search in accordance with the Preferred Reporting Items for Systematic review and Meta-analysis (PRISMA) guidelines was conducted using PubMed, Embase, MEDLINE and Cochrane databases. Exclusion criteria included patients < 18 years of age, follow-up <11 months, and a score < 6 on the National Institute of Health quality assessment tool. Results. 15 articles, encompassing 631 PJIs in 626 patients, were included in the final analysis, all level IV case series. The quality of many studies was impeded by a retrospective design (14/15), a relative small study population (10 out of 15 studies had less than 50 patients), selection bias, and remarkable heterogeneity in terms of catheter type, antibiotic type, dose and duration of IA antibiotics and techniques of surgical revision. 347 were chronic infections, 66 acute infections and 218 unknown. The majority was treated with single-stage revision with adjuvant IA antibiotic infusion (499/631, 79.1%). The remaining PJIs were treated with stand-alone IA antibiotic infusion (77/631, 12.2%), DAIR with adjuvant IA antibiotic infusion (36/631, 5.7%) or two-stage revision with adjuvant IA antibiotic infusion (19/631, 3.0%). Mean duration of IA antibiotic infusion was 19 days (range 3–50), although most patients received a combination of both IA and systemic (IV or PO) antibiotics. An overall failure rate (defined as failures of infection eradication/total PJIs) of approximately 11% was found. The use of IA antibiotic infusion as a stand-alone treatment was associated with a higher failure rate. In total 117 complications occurred in 631 cases (18.5%). Of these, 71 were non-catheter-related (60.7%) and 46 were catheter-related (39.3%). The most common catheter-related complications were premature loss of the catheter (18/46), developing a fistula (5/46), and elevated blood urea nitrogen (BUN) and creatinine levels (12/46). Conclusions. Due to the lack of comparative studies the (added) benefit of IA antibiotic infusion in the treatment of PJI remains uncertain. From a theoretical point of view it seems likely that is should not be used as a stand-alone treatment. A prospective randomized controlled trial using a well-described infusion protocol is needed to see if the potential benefits justify the increased costs, labour and catheter-related complications of this treatment modality

Aim. Serum parameters continue to be a focus of research in diagnosing periprosthetic joint infections (PJI). Several workgroups have recently proposed serum Albumin-Globulin-Ratio (AGR) as a potential new biomarker. Due to controversies in the literature, its usability in clinical practice remains uncertain. The aim of this study was to assess the value of serum AGR in diagnosing PJI preoperatively, especially in comparison with the well-established marker C-reactive Protein (CRP). Method. From January 2015 to June 2022, patients with indicated revision hip (rTHA) and knee (rTKA) arthroplasty were included in this retrospective cohort study of prospectively collected data. A standardized diagnostic workup was performed using the 2021 European Bone and Joint Infection Society (EBJIS) definition of PJI, excluding CRP. Diagnostic accuracies of serum AGR and CRP were calculated by receiver operating characteristic curve (ROC) analysis. A z-test was used to compare the area under the curves (AUC). Results. A total of 275 patients with rTHA and rTKA were included, 144 joints (52.4%) were identified as septic. Decreased AGR and elevated CRP were strongly associated with PJI, optimal diagnostic thresholds were calculated with 1.253 and 9.4 mg/L, respectively. Sensitivities were 62.5% (95%-confidence interval: 54.3–70.0) and 73.6% (65.8–80.1), and specificities 84.7% (77.5–89.9) and 87.8% (80.9–92.4), respectively. CRP showed a significantly higher AUC than AGR (0.807 (0.761–0.853) and 0.736 (0.686–0.786); p<0.0001). Subgroup analysis of acute versus chronic infections yielded significantly higher diagnostic accuracies in acute PJI for both parameters (p<0.0001). Similar results were observed when focusing on the causative microorganism; a better diagnostic performance was observed in high-virulence PJI compared to low-virulence PJI (p≤0.005). Furthermore, higher AUCs were calculated in knee PJI compared with hip PJI, with a significant difference for AGR (p=0.043). Conclusions. Due to its limited diagnostic accuracy, serum AGR cannot be recommended as an additional marker for diagnosing PJI. Serum parameters are generally unspecific and can be influenced by comorbidities and other foci of infection. Additionally, parameters may remain within normal levels in low-grade PJI. Evaluating AGR, further possible pitfalls must be considered, for example an increased latency until bottom values are reached and the impact of malnutrition

Aim. To describe the risk factors, microbiology and treatment outcome polymicrobial prosthetic joint infections (PJI) compared to monomicrobial PJI. Methods. Between January 2011 and December 2021, a total of 536 patients were diagnosed with PJI at our institution. Clinical records were revised, and 91(16.9%) had an isolation of two or more pathogens. Age, sex, previous conditions, Charlson comorbidity score, previous surgery, PJI diagnosis and surgical and antibiotic treatment, from the index surgery onwards were reviewed and compared between groups. Results. Polymicrobial PJI success rate was 57.1%, compared to 85.3% of the monomicrobial PJI(p=0.0036). There were no statistically significative differences between acute and chronic infections. In terms of related risk factors, revision surgery(p=0.0002), fracture(p=0.002), tobacco(p=0.0031) and Body Mass Index (BMI) between 20–25(p=0.0021) were associated to monomicrobial PJI, whereas overweight(p=0.005) and obesity(p=0.02) were linked to polymicrobial PJI. Regarding pathogens, the most common microorganism isolated in monomicrobial was S.aureus (33.5%), followed by S. epidermidis(20%) and gram negative bacilli (12.2%); while S. epidermidis(56%), gram negative bacilli (41.8%) and E.colli (30.8%) were the most frequent in the polymicrobial PJI. Enterococci(p=0.0008), S. epidermidis(p=0.007), E.colli (p=0.0008), gram negative bacilli (p=0.00003) and atypical bacteria (p=0.00001) statistically significative linked to polymicrobial PJI; while S.aureus (p=0.018) was related to monomicrobial PJI. Conclusion. Polymicrobial PJI showed worse outcome compared to monomicrobial PJI in our cohort. In terms of risk factors, overweight, obesity and some pathogens like gram negative bacilli, atypical bacteria, enterococci, S. epidermidis and E.colli were associated with Polymicrobial PJI

Aim. Osteomyelitis (OM) is a debilitating infection of the bone that originates from hematogenous spreading of microbes or contamination after surgery/fracture. OM is mainly caused by the opportunistic bacterium Staphylococcus aureus (SA), which can evade the host immune response, acquire antibiotic resistance and chronically colonize the musculoskeletal tissue . 1,2. , yet the underlying molecular and cellular processes are largely unclear. This study aimed to characterize the pathogenetic mechanisms of SA-OM with a focus on the long pentraxin 3 (PTX3), a soluble pattern recognition molecule and bone tissue component that is emerging as a new player in osteoimmunology . 3. and a diagnostic marker of periprosthetic joint infections, a common form of OM. 4. . Method. A murine model of OM based on intra-bone injection of SA was developed that closely mimicked surgery/trauma-related OM in humans and allowed addressing the role of PTX3 in gene-modified (Ptx3-/-) animals. Local and systemic infection and inflammation were assessed via microbiology, flow cytometry, histochemistry and microCT techniques. Results. SA-injected mice developed chronic infection with measurable levels of viable bone-resident bacteria up until 30 days from microbial challenge. The infection was confined to the treated limbs only and accompanied by extensive tissue remodelling. The bacterial load was higher in WT than Ptx3. -/-. animals at 6 and 14 days from SA injection. Accordingly, WT mice had enhanced systemic inflammation with expanded innate immune compartment in the spleen and increased serum levels of inflammatory cytokines and chemokines. PTX3 levels were higher in SA- than vehicle (PBS)-injected WT animals both in the serum and bone tissue. Furthermore, administration of a PTX3-targeting antibody reduced the bacterial burden in the bones of SA-injected WT mice. Conclusions. In a mouse model of SA-OM, genetic deficiency of PTX3 protected from infection and inflammation, pointing to this pentraxin as a crucial player in OM pathogenesis and a novel therapeutic target in bone infections. The study was approved by the Italian Ministry of Health (approval n. 520/2019-PR issued on 19/07/2019) and supported by Fondazione Beppe and Nuccy Angiolini

Aim. Antibiotics have limited activity in the treatment of multidrug-resistant or chronic biofilm-associated infections, in particular when implants cannot be removed. Lytic bacteriophages can rapidly and selectively kill bacteria, and can be combined with antibiotics. However, clinical experience in patients with surgical infections is limited. We investigated the outcome and safety of local application of bacteriophages in addition to antimicrobial therapy. Method. 8 patients (2 female and 6 male) with complex orthopedic and cardiovascular infections were included, in whom standard treatment was not feasible or impossible. The treatment was performed in agreement with the Article 37 of the Declaration of Helsinki. Commercial or individually prepared bacteriophages were provided by ELIAVA Institute in Tbilisi, Georgia. Bacteriophages were applied during surgery and continued through drains placed during surgery three times per day for the following 5–14 days. Follow-up ranged from 1 to 28 months. Results. Median age was 57 years, range 33–75 years. Two patients were diagnosed with a persistent knee arthrodesis infection, one chronic periprosthetic joint infection (PJI), one cardiovascular implantable electronic device (CIED) infection and four patients with left ventricular assist device (LVAD) infection. The isolated pathogens were multi-drug-resistant Pseudomonas aeruginosa (n=3), methicillin-sensitive Staphylococcus aureus (n=4), methicillin-resistant Staphylococcus aureus (MRSA) (n=1) and methicillin-resistant Staphylococcus epidermidis (MRSE) (n=1). 4 infections were polymicrobial. 5 patients underwent surgical debridement with retention of the implant, 1 patient with PJI underwent the exchange of the prosthesis and one patient with LVAD infection was treated conservatively. All patients received intravenous and oral antibiotic therapy and local application of bacteriophages. At follow-up of 12 month, 5 patients were without signs or symptoms of infection, whereas in one patient with LVAD infection, a relapse was observed with emergence of phage-resistant Pseudomonas aeruginosa. In this patient, no surgical revision was performed. Conclusions. Bacteriophage therapy may represent a valid additional approach, when standard antimicrobial and surgical treatment is not possible or feasible, including in difficult-to-treat infections. In our case series, 5 of 6 patients were infection free after 1 year. Further studies need to address the optimal bacteriophage administration route, concentration, duration of treatment and combination with antimicrobials

This study aimed to identify long-term physical and psychosocial health outcomes in children with overwhelming musculoskeletal sepsis. Children admitted to the Paediatric Intensive Care Unit (PICU) from 1st January 2002 to 31st December 2017 with a musculoskeletal focus of infection were identified. A medical notes review was completed to determine survival and morbidity. Present-day clinical assessment of the musculoskeletal and respiratory systems along with questionnaires on health-related quality of life, mental health and sleep were performed. 70 patients were identified over 15 years. Seven children died acutely (five Pasifika and two Māori children) indicating 10% mortality. Recurrence/chronic infection affected 23%. Growth disturbance affected 18%. The hip joint and proximal femur suffered the worst long-term complications. Children under 2 years most at risk of long-term disability. No patients had chronic respiratory illness beyond 90 days. Fifteen children had symptoms of acute neurological impairment, three of whom had permanent acquired brain injury. Twenty-six survivors (41%) were assessed a mean of 8.2 years (SD 4.5, range 2– 18 years) after discharge. Health-related quality of life scores were on par with normative data. All patients who underwent pulmonary function tests had normal results. Six patients and eight parents screened positive for moderate to severe post-traumatic stress disorder. Paediatric multifocal musculoskeletal sepsis can result in complex illness with multi-organ complications for some children. Māori and Pasifika children are most at risk. Children under 2 years and those with proximal femur and/or hip involvement are most likely to have chronic musculoskeletal sequelae and permanent disability. Other outcomes are favourable with no evidence of chronic lung disease or mean reduced quality of life. A period of rehabilitation for children with identified acquired brain injury should be part of discharge planning