Challenging Diagnostics of Biofilm Associated Periprosthetic Infection in Immunocompromised Patient: A Clinical Case

Abstract BACKGROUND: Periprosthetic joint infection (PJI) is a devastating complication of joint arthroplasty. The identification of microorganisms in biofilm-related PJI is challenging yet significant stage of the treatment process. Medical microbiology methods, such as pure culture isolation, remain the gold standard. However, the error rate of classical methods may vary from 10% to as high as 42% due to the inability to detect bacteria growing within biofilms. Other methods of detection are being explored to improve the management of PJI. AIM: Accurate identification of PJI contributing microorganisms in a patient with acute postoperative PJI after total hip joint arthroplasty and systemic lupus erythematosus in anamnesis. METHODS: We used microbial culture methods followed by scanning electron microscopy (SEM). RESULTS: Perioperative an intraoperative cultural analysis of 8 different culture samples of tissue and prosthetic origin was insufficient for bacterial or fungal detection. Scanning electron microscopy revealed detailed biofilm visualisation on the surface of the prosthetic component. The biofilm exterior was composed of microbial clusters made of 10 or more cells with either pear- or bottle-shaped morphology, 3-6 mcm in length and 1.5-3 mcm in diameter. Rod-shaped microorganisms of 0.7-1 mcm length and up to 0.5 mcm in diameter were found adjacent to these clusters. CONCLUSION: Additional methods for PJI agents’ detection are time-and cost-effective in the case of the challenging diagnostics of biofilm-related PJI, particularly in immunocompromised patients. Using combined diagnostic approaches increases the accuracy of detection, justifies treatment strategies and improves clinical outcomes

Efficiency of two-stage revision arthroplasty in management of periprosthetic knee and hip joint infection

This technique involves removal of implant components, debridement of the purulent focus and installation of a cement spacer which is subsequently replaced with a permanent implant after 3–9 months. Purpose To evaluate mid-term results of two-stage surgical treatment of patients with chronic periprosthetic infection of the knee and hip joints. Materials and methods Treatment outcomes of 172 patients with periprosthetic infection who underwent two-stage revision arthroplasty in the period from 2011 to 2015 were assessed. Among them, 113 patients developed infection after hip replacement and 59 patients had infected knee joint. The average follow-up period was 4 ± 1.58 years (range: 2 to 6 years). Results Out of 113 two-stage procedures of hip joint revision, 102 (90.2 %) cases showed an arrest of infection. Four (3.6 %) patients with recurrence of the purulent process underwent resection arthroplasty, another four (3.6 %) rejected to replace the spacer with an implant, and three (2.6 %) had a two-stage re-revision. Out of 60 (59 patients) procedures of a two-stage knee joint revision, infection was arrested in 50 (83.3 %) cases; eight (13.4 %) had recurrence and underwent knee arthrodesis. One (1.6 %) refused to replace a spacer for an implant, and one more (1.6 %) had a two-stage repeated revision. Conclusions Two-stage knee and hip revision arthroplasty using a cement spacer is an effective option for treatment of chronic periprosthetic infection. It provides infection control in 86.7 % (83.3 % for knee and 90.2 % for hip joints) of cases in the mid-term follow-up period up to 5 years. However, the rate of re-infection remains significant and reaches 13.3 % (9.8 % for hip and 16.7 % for knee joints)

Outcome of bilateral periprosthetic hip infection management

Introduction Infection is a devastating complication after joint arthroplasty. In most cases of purulent infection, surgeons are forced to perform revision of the artificial joint. This is caused by the ability of microorganisms to adhere on the implant surface. Periprosthetic infection is a heavy burden both for patients due to a significant level of the disease recurrence and for medical institutions because of high medical treatment costs. Methods The analysis of the treatment outcome in a female patient with bilateral periprosthetic hip infection was conducted. One- and two-stage revisions were performed. Results The treatment measures stopped the purulent inflammatory process (according to Delphi) and restored the functional state of both hip joints (HHS of 79 points on the left and 93 points on the right side). Discussion Treatment of periprosthetic infection is a complex clinical task, which requires a personalized and comprehensive approach that includes implementation of the basic principles of diagnosis and treatment of the disease, understanding of this pathology, and teamwork. One- and two-stage revisions provide a successful arrest of periprosthetic infection and functional restoration of the affected joint

Dose-Dependent Effects of Cold Atmospheric Argon Plasma on the Mesenchymal Stem and Osteosarcoma Cells In Vitro

The antimicrobial, anti-inflammatory and tissue-stimulating effects of cold argon atmospheric plasma (CAAP) accelerate its use in various fields of medicine. Here, we investigated the effects of CAAP at different radiation doses on mesenchymal stem cells (MSCs) and human osteosarcoma (MNNG/HOS) cells. We observed an increase in the growth rate of MSCs at sufficiently low irradiation doses (10–15 min) of CAAP, while the growth of MNNG/HOS cells was slowed down to 41% at the same irradiation doses. Using flow cytometry, we found that these effects are associated with cell cycle arrest and extended death of cancer cells by necrosis. Reactive oxygen species (ROS) formation was detected in both types of cells after 15 min of CAAP treatment. Evaluation of the genes’ transcriptional activity showed that exposure to low doses of CAAP activates the expression of genes responsible for proliferation, DNA replication, and transition between phases of the cell cycle in MSCs. There was a decrease in the transcriptional activity of most of the studied genes in MNNG/HOS osteosarcoma cancer cells. However, increased transcription of osteogenic differentiation genes was observed in normal and cancer cells. The selective effects of low and high doses of CAAP treatment on cancer and normal cells that we found can be considered in terms of hormesis. The low dose of cold argon plasma irradiation stimulated the vital processes in stem cells due to the slight generation of reactive oxygen species. In cancer cells, the same doses evidently lead to the formation of oxidative stress, which was accompanied by a proliferation inhibition and cell death. The differences in the cancer and normal cells’ responses are probably due to different sensitivity to exogenous oxidative stress. Such a selective effect of CAAP action can be used in the combined therapy of oncological diseases such as skin neoplasms, or for the removal of remaining cancer cells after surgical removal of a tumor

Planarians as an In Vivo Experimental Model for the Study of New Radioprotective Substances

Ionising radiation causes the death of the most actively dividing cells, thus leading to depletion of the stem cell pool. Planarians are invertebrate flatworms that are unique in that their stem cells, called neoblasts, constantly replace old, damaged, or dying cells. Amenability to efficient RNAi treatments, the rapid development of clear phenotypes, and sensitivity to ionising radiation, combined with new genomic technologies, make planarians an outstanding tool for the discovery of potential radioprotective agents. In this work, using the well-known antioxidant N-acetylcysteine, planarians are, for the first time, shown to be an excellent model system for the fast and effective screening of novel radioprotective and radio-sensitising substances. In addition, a panel of measurable parameters that can be used for the study of radioprotective effects on this model is suggested

Primary data from the local registry of periprosthetic hip infection at the National Ilizarov Medical Research Centre for Traumatology and Orthopaedics

Background. Obtaining accurate data on the epidemiology of periprosthetic joint infection (PJI) of the hip in the Russian Federation is a challenging task, which is associated with the peculiarities of statistical registration of complications and the lack of approved routing schemes. The aim of the study — to provide the results of primary analysis of the data from the local registry of hip periprosthetic infection, which reflects all the treatment cases from 01.01.2020 to 31.12.2020. Methods. Since 2021, the Center has been working on retrospective input of the data on patients PJI of the hip treated at the clinic into the electronic version of the registry. The information was collected by studying archived medical records and a medical information system, by examining patients in the outpatient clinic, and by interviewing patients via mobile phone and e-mail. During the period, we treated 449 patients with hip periprosthetic infection. The mean patients’ age was 55.6±12.6 years (Ме — 57; 95% CI: 54.4-56.8). Male patients accounted for 61.6% (n = 277). Results. We were able to evaluate the treatment results in 84% (n = 377) of patients. The mean follow-up period was 5.92±2.55 years (Me — 6; 95% CI: 2.39-2.73). In more than 90% (n = 407) of cases, the infection was classified as chronic (more than 3 weeks of manifestation). At the admission 76,8% (n = 345) of patients had a fistula communicating with the joint cavity. The percentage of lethal outcomes due to sepsis was 1,7% (8/449); recurrences of hip PJI was observed in 6.2% (28/ 449) of cases. Resolution of infection has been achieved in 67% (300/449) of cases. Conclusions. The primary analysis of the data from the local registry of hip periprosthetic infection of the national Ilizarov Center of Traumatology and Orthopedics showed that the average age of patients with hip PJI in our country is significantly lower than in the known national registries. At the same time, the infectious agents were similar: Gram-positive microorganisms accounted for more than 55%. The analysis of the registry data shows a significant decrease in the PJI recurrence rate over the last 5 years

Mitogen-like Cerium-Based Nanoparticles Protect <i>Schmidtea mediterranea</i> against Severe Doses of X-rays

Novel radioprotectors are strongly demanded due to their numerous applications in radiobiology and biomedicine, e.g., for facilitating the remedy after cancer radiotherapy. Currently, cerium-containing nanomaterials are regarded as promising inorganic radioprotectors due to their unrivaled antioxidant activity based on their ability to mimic the action of natural redox enzymes like catalase and superoxide dismutase and to neutralize reactive oxygen species (ROS), which are by far the main damaging factors of ionizing radiation. The freshwater planarian flatworms are considered a promising system for testing new radioprotectors, due to the high regenerative potential of these species and an excessive amount of proliferating stem cells (neoblasts) in their bodies. Using planarian Schmidtea mediterranea, we tested CeO2 nanoparticles, well known for their antioxidant activity, along with much less studied CeF3 nanoparticles, for their radioprotective potential. In addition, both CeO2 and CeF3 nanoparticles improve planarian head blastema regeneration after ionizing irradiation by enhancing blastema growth, increasing the number of mitoses and neoblasts’ survival, and modulating the expression of genes responsible for the proliferation and differentiation of neoblasts. The CeO2 nanoparticles’ action stems directly from their redox activity as ROS scavengers, while the CeF3 nanoparticles’ action is mediated by overexpression of “wound-induced genes” and neoblast- and stem cell-regulating genes

Analysis of the economic and clinical effectiveness of one- and two-stage revisions in the treatment of periprosthetic infection of the hip joint (literature review)

Introduction Infection is a devastating complication of joint replacement surgery and is associated with significant medical costs of treatment and rehabilitation. This review is based on the analysis of modern domestic and foreign literature and demonstrates the problem of periprosthetic joint infection (PJI) in terms of etiology, pathogenesis, diagnosis and surgical treatment options for PJI, as well as economic costs in different countries. Currently, two-stage revision arthroplasty is the most used treatment method in the world. At the same time, the number of publications on the effectiveness of one-stage revision arthroplasty in PJI has been increasing every year. Purpose Analysis of the clinical and economic efficiency of one- and two-stage revision arthroplasty interventions for suppression of the purulent inflammatory process and their medical costs Materials and methods The literature search was carried out in open electronic databases of scientific literature PubMed, eLIBRARY and Scopus. The search depth was 22 years. Sixteen articles were selected for economic analysis in which the expenditures on PJI management in developed and developing countries were reported. Also, there were 15 studies on evaluating the effectiveness of two-stage revisions and 26 articles on evaluating the effectiveness of one-stage revisions and 15 articles on analyzing the functional state of the affected limb according to the Harris Hip Score. The following inclusion criteria were used: systematic reviews, literature reviews, cohort studies on the topic of periprosthetic infection. Results The rate of PJI arrest with one-stage method was 89.5 % (Me-88.6; Q1-86 Q3-94) and the average mortality was 2.23 ± 2.24 (Me-1.2 Q1-0.8 Q3 -2.7). The rate of PJI suppression by two-stage method averaged 91.4 % (Me-93;Q1-88.2 Q3-96) with an average mortality rate of 3.2 %. The functional HHS after onestage replacement averaged 81.8 points, and after two-stage revision arthroplasty it was 77.4 points. The economic cost of treating one patient with PJI, according to various authors, varies from 6,500 to 150,000 dollars. Conclusions One-stage revision is cost-effective, has better functional parameters and lower mortality with comparable results in PJI arrest if strict adherence to indications is followed

PVP-stabilized tungsten oxide nanoparticles: pH sensitive anti-cancer platform with high cytotoxicity

Photochromic tungsten oxide (WO3) nanoparticles stabilized by polyvinylpyrrolidone (PVP) were synthesized to evaluate their potential for biomedical applications. PVP-stabilized tungsten oxide nanoparticles demonstrated a highly selective cytotoxic effect on normal and cancer cells in vitro. WO3 nanoparticles were found to induce substantial cell death in osteosarcoma cells (MNNG/HOS cell line) with a half-maximal inhibitory concentration (IC50) of 5 mg/mL, while producing no, or only minor, toxicity in healthy human mesenchymal stem cells (hMSc). WO3 nanoparticles induced intracellular oxidative stress, which led to apoptosis type cell death. The selective anti-cancer effects of WO3 nanoparticles are due to the pH sensitivity of tungsten oxide and its capability of reactive oxygen species (ROS) generation, which is expressed in the modulation of genes involved in reactive oxygen species metabolism, mitochondrial dysfunction, and apoptosis

The Strong Protective Action of Ce3+/F&minus; Combined Treatment on Tooth Enamel and Epithelial Cells

We studied the toxic effects of cerium and fluoride species on human dental pulp stem cells and epithelial cells of Cercopithecus aethiops as a surrogate for the human oral mucosa. The sequential use of CeCl3 and NH4F solutions in equimolar sub-toxic concentrations enabled the possible toxic effects of individual components to be avoided, ensuring the preservation of the metabolic activity of the cells due to the formation of CeF3 nanoparticles. Cerium fluoride nanoparticles and terbium-doped cerium fluoride nanoparticles exhibited neither cytotoxicity nor genotoxicity to dental pulp stem cells, even at high concentrations (10&minus;4 M). In millimolar concentrations (from 10&minus;5&ndash;10&minus;6 M), these nanoparticles significantly increased the expression of genes responsible for the cell cycle, differentiation and proliferation. The formation of cerium fluoride on the surface of the mucous membrane and teeth provided protection against the development of carious lesions, periodontitis, ROS attacks and other inflammatory diseases of the oral cavity. Luminescent CeF3: Tb nanoparticles enabled the visualization of tooth enamel microcracks