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Background . Ceftazidime/Avibactam (C/A) and Ceftolozane/Tazobactam (C/T) are two novel antibacterial agents with a known efficacy on Gram-negative bacteria (GNB). Objectives . We aimed to describe the efficacy and safety of surgical management combined with C/A or C/T treatment for bone and joint infections (BJI). Patients and Methods . We conducted an observational, bi-centric study of patients treated with C/A or C/T for a BJI between May 2016 and June 2019. Failure was defined as a need for an unplanned additional antibiotic treatment or orthopedic surgery or death due to the BJI until the patient's latest visit. Results . Overall, 15 patients were included. Nine patients were treated with C/A, mainly for polymicrobial BJI due to multidrug-resistant (MDR) bacteria (Enterobacteriaceae n=7). Six patients were male; median age was 66 years-old, and median Charlson comorbidity index (CCI) was 5. It was the first septic episode on the site in 3/9 patients. Cure rate was 7/9 (median follow-up: 272 days). Two patients showed C/A-related confusion. Five patients were treated with C/T, for BJI involving MDR-Pseudomonas aeruginosa. Four patients were male; median age was 53 years-old, and median-CCI was 2. All patients had previous septic episodes on infectious site. Cure rate was 3/5 (median follow-up: 350 days). One patient was successfully treated by C/T then C/A for multistage spondylodiscitis. Conclusion . In our experience, C/A and C/T were two effective and safe options, even as salvage treatment of BJI due to MDR GNB despite the absence of label, but more data are warranted.

International audience; The Forensic Science Institute of the French "Gendarmerie Nationale" (IRCGN™) developed in 2015 an ISO 17025 certified mobile DNA laboratory for genetic analyses. This Mobil'DNA laboratory is a fully autonomous and adaptable mobile laboratory to perform genetic analyses in the context of crime scenes, terrorism attacks or disasters.To support the hospital taskforce in Paris during the peak of the COVID-19 epidemic, we adapted this mobile genetic laboratory to perform high-throughput molecular screening for coronavirus SARS-CoV-2 by real-time PCR. We describe the adaptation of this Mobil'DNA lab to assist in Coronavirus SARS-CoV-2 diagnosis.

The Omicron SARS-CoV-2 variant of concern is driving the COVID pandemic at a pace never seen before. When the threat of overwhelming healthcare systems balances the hope of achieving herd immunity, providing booster shots and vaccinating fragile individuals can still be attempted in France to prevent death and hospitalizations.

In the context of SARS-Cov-2 virus disease (COVID-19) pandemic, molecular diagnostic tools were rapidly developed as there are fundamental for a rapid detection of infected people. In this context, and in order to optimize the manipulations and reduce the time to get results, we report the successful use of a sampling tool for COVID-19 diagnosis named microFLOQ® Direct (MFD). Hundred upper respiratory specimens sampled from patients with potential COVID-19 were evaluated using MFD, and results were compared to the results obtained by standard sampling procedure using dry swabs and physiologic serum as the transport medium. MFD results compared to results issued from the classic RNA purification and amplification steps from transport medium showed that MFD can be directly used for RT-PCR analysis without the preliminary inactivation and extraction steps. So, MFD could limit handling errors compared to the different treatment steps with dry swabs and transport medium. It therefore limits the risk of contamination, simplify the analytical process and enables to get results in less than 2 hours. We also show that the MFD kit is operational as a screening tool in the field of molecular detection of viral and bacterial diseases during an outbreak and then it can be used for public health or agro-veterinary purposes.

Cross-contamination of biological samples during handling and preparation, is a major issue in laboratory setups, leading to false-positives or false-negatives. Sample carryover residue in pipette tips contributes greatly to this issue. Most pipette tips on the market are manufactured with hydrophobic polymers that are able to repel high surface tension liquids, yet they lack in performance when low surface tension liquids are involved. This presents an obstacle for pipette tips as inaccuracies and loss in precision arise when low surface tension liquids such as viscous oils are pipetted. Here we propose the use of lubricant-infused surface (LIS) technology to achieve omniphobic properties in pipette tips. Using a versatile and simple design, the inner lumen of commercially available pipette tips was coated with a fluorosilane (FS) layer using chemical vapor deposition (CVD). We show that after lubricating the tips through simply pipetting up and down a fluorinated lubricant, the surface free energy of the tips drastically decreased enabling them to attain low retention properties. Contact angle measurements reveals that the treated pipette tips have enhanced omniphobic properties. The repellent behavior of the lubricant-infused pipette tips against physical adsorption is investigated through pipetting a food coloring dye as well as human blood samples and are compared to the untreated tips. The results show significantly less amount carryover residue when the lubricant-infused tips are utilized compared to commercially available ones.

Corynebacterium striatum is a ubiquitous colonizer of human skin and mucous membranes. It is increasingly involved in infections, especially with prosthetic devices or in immunocompromised individuals. Microbiological diagnosis is challenging and bacterial resistance is a major concern. We performed a retrospective study of monomicrobial bone and joint infections (BJI) due to C. striatum in two referral centers from April 2012 to July 2017. We collected the patients' clinical and microbiological characteristics and outcomes. We also performed a literature review of BJI due to C. striatum. We identified 12 cases (nine prosthetic joint infections, one osteosynthetic device infection, one non-union, and one arthritis) in 11 patients, five of which were immunocompromised. Microbiological diagnosis was performed with prolonged culture media. Ten out of 12 strains were susceptible to aminopenicillin, a drug class not recommended for testing by the EUCAST/CASFM guidelines, and 8/12 patients were treated with amoxicillin-rifampicin. The cure rate was 8/12, after a median follow-up period of 487.5 days (IQR 140.3-1348.5). Twelve cases of BJI due to C. striatum were previously reported. Among them, 5/12 patients were immunocompromised, 3/12 cases were acute BJI, and 2/12 were device-related infections. The diagnosis was performed by PCR in one case, and 10/12 patients were treated with glycolipopeptides, with a cure rate of 11/12. We report the largest cohort of monomicrobial BJI with C. striatum. Determination of aminopenicillin susceptibility is essential since it is frequently active in our experience, even in BJI. The cure rate of this infection seems high.

Blood culture bottles (BCBs) are commonly used for the diagnosis of infections associated with orthopedic devices. Although Cutibacterium acnes is an important pathogen in orthopedics, relatively little is known about its growth characteristics in BCBs. This prompted us to analyze the influence of bacterial genotype and clinical significance on time-to-detection (TTD) in BCBs.We reviewed 59 cases of orthopedic device-related infections in which at least one intraoperative specimen yielded a pure C. acnes culture from anaerobic BCBs (BD Bactec Lytic/10 Anaerobic/F; Lytic-Ana) and/or solid media. A strain was considered infectant if the same genotype was present in two or more intraoperative samples. From these cases, we isolated a total of 72 unique C. acnes strains belonging to four multilocus sequence type clonal complexes (CCs): CC18, CC28, CC36 and CC53. Growth rate and TTD in Lytic-Ana BCB were studied under experimental conditions (inoculation of standard inoculum) and in clinical samples (inoculation of periprosthetic tissue samples).Median TTD values were shorter for CC53 compared to other CCs under experimental conditions (69 vs. 103 h; p 0.001) and from clinical specimens (70 vs. 200 h; p = 0.02). Infectant strains had a shorter median TTD compared to contaminant strains in a clinical situation, while the difference was not observed under experimental conditions.The detection dynamics of C. acnes in Lytic-Ana BCBs were associated with genotype. Thus, TTD not only reflects the bacterial load in clinical samples, but may also reflect the intrinsic properties of the clonal complex of C. acnes.

International audience; Objectives: Limited data have been reported regarding osteomyelitis due to carbapenemase-producing Enterobacteriaceae (CPE), including co-infections with extended-spectrum β-lactamase (ESBL)-producing micro-organisms.Methods: We conducted a retrospective study in a reference centre for bone and joint infections from 2011 to 2019 among patients infected with CPE.Results: Nine patients (mean age 46.8 ± 16.6 years), including three with infected implants, were identified. Infections were mostly polymicrobial (n = 8/9), including Staphylococcus aureus (n = 6/9). CPE were mainly OXA-48-type, associated with ESBL-producing Enterobacteriaceae (n = 8/9), of which 5/9 isolates were Klebsiella pneumoniae. Control of the infection was achieved in seven cases.Conclusions: CPE osteomyelitides are essentially polymicrobial and fluoroquinolone-resistant infections, highlighting the need for efficient surgery with implant removal.

The increasing incidence of carbapenemase-producing Gram-negative bacilli (C-PGNB) represents a major public health challenge. Rapid detection of digestive colonization with C-PGNB is fundamental to control their spread. We performed the validation of a rapid protocol for C-PGNB detection directly on rectal swabs. We developed a protocol combining enrichment by a rapid selective subculture of the rectal swab medium and realization of a Resist-4 O.K.N.V. K-SeT test on the bacterial pellet obtained. The limit of detection and performances of this protocol were validated in vitro on 52 C-PGNB strains spiked on a calibrated sample suspension and confirmed in clinical settings on 144 rectal swabs sampled from patients with C-PGNB digestive colonization (n = 48) and controls (patients with extended-spectrum beta-lactamase [ESBL] colonization [n = 48] and without carbapenemase/ESBL [n = 48]). The protocol detected, with 100% sensitivity, the presence of the 15 OXA-48-, 14 KPC-, 13 NDM-, and 10 VIM-producing GNB from 10(3) CFU/ml. The limit of detection was 2 × 10(2) CFU/ml. Among the 48 C-PGNB-containing rectal swabs of the validation cohort, 46 were accurately detected. False negative were observed for 1 NDM-producing Acinetobacter baumannii strain and 1 OXA-48-producing Escherichia coli strain. The 96 control swabs were negative. Sensitivity and specificity for C-PGNB detection were 97.7% (95% confidence interval [CI], 87.7 to 100) and 100% (95% CI, 96.2 to 100). The negative likelihood ratio was 0.04 (95% CI, 0.01 to 0.16). Considering a C-PGNB digestive colonization prevalence between 0.01% and 0.1%, positive and negative predictive values were 100%. Our protocol is a rapid and low-cost method detecting accurately the digestive colonization with carbapenemase-producing Enterobacteriaceae in 4 h without any requirement for specific equipment.

The emergence and quick spread of SARS-CoV-2 has pointed at a low capacity response for testing large populations in many countries, in line of material, technical and staff limitations. The traditional RT-qPCR diagnostic test remains the reference method and is by far the most widely used test. These assays are limited to a few probe sets, require large sample PCR reaction volumes, along with an expensive and time-consuming RNA extraction step. Here we describe a quantitative nanofluidic assay that overcomes some of these shortcomings, based on the BiomarkTM instrument from Fluidigm. This system offers the possibility of performing 4608 qPCR end-points in a single run, equivalent to 192 clinical samples combined with 12 pairs of primers/probe sets in duplicate, thus allowing the monitoring of SARS-CoV-2 including the detection of specific SARS-CoV-2 variants, as well as the detection other pathogens and/or host cellular responses (virus receptors, response markers, microRNAs). The 10 nL-range volume of BiomarkTM reactions is compatible with sensitive and reproducible reactions that can be easily and cost-effectively adapted to various RT-qPCR configurations and sets of primers/probe. Finally, we also evaluated the use of inactivating lysis buffers composed of various detergents in the presence or absence of proteinase K to assess the compatibility of these buffers with a direct reverse transcription enzymatic step and we propose several protocols, bypassing the need for RNA purification. We advocate that the combined utilization of an optimized processing buffer and a high-throughput real-time PCR device would contribute to improve the turn-around-time to deliver the test results to patients and increase the SARS-CoV-2 testing capacities.

Immune checkpoint inhibitors (ICIs) are commonly used in patients with advanced non-small cell lung cancer (NSCLC). An unmet need remains for new biomarkers associated with ICIs. In this study, consecutive patients with advanced NSCLC treated with nivolumab or pembrolizumab were included. Plasma at ICIs initiation was prospectively collected and a multiplex ELISA assay testing 48 cytokines and growth factors was performed. Exploratory endpoints were the association between plasma biomarkers with outcome and grade III&ndash, IV immune related adverse events (irAEs). Thirty-five patients were included. Patients without clinical benefit (n = 22) had higher pre-ICI soluble Hepatocyte Growth Factor (sHGF) (210.9 vs. 155.8 pg/mL, p = 0.010), lower pre-ICI soluble Fibroblast Growth Factor (sFGF) (4.0 vs. 4.8 pg/mL, p = 0.043) and lower pre-ICI interleukine-12 (IL-12) (1.3 vs. 2.2 pg/mL, p = 0.043) concentrations. Patients with early progression (n = 23) had higher pre-ICIs sHGF (206.2 vs. 155.8 pg/mL, p = 0.025) concentrations. Patients with low sHGF levels at ICIs initiation had longer progression-free survival and overall survival than those with high sHGF levels: respectively 2.5 vs. 8.0 months (p = 0.002), and 5.5 vs. 35.0 months (p = 0.001). TNF-&alpha, IL-16, IL-12p40 and MCP3 were associated with high grade irAEs. This study shows the potential association between several plasma biomarkers with outcome and grade 3&ndash, 4 IrAEs in advanced NSCLC treated with ICIs.

International audience; BACKGROUND: Preoperative synovial fluid culture is pivotal in the early diagnosis of prosthetic joint infection (PJI) but may yield false-positive and false-negative results. We evaluated the predictive value of synovial fluid culture results combined with the measurement of serum anti-staphylococcal antibodies (SASA). QUESTIONS/PURPOSES: (1) For hip and knee PJI, does combining positive SASA results with preoperative synovial culture results improve the positive predictive value (PPV) of preoperative synovial fluid culture alone? (2) Does combining preoperative synovial fluid culture results with a positive cell count and differential result increase the PPV of preoperative synovial fluid culture alone? (3) What proportion of isolated organisms exhibit concordance in antibiotic susceptibility: preoperative aspiration versus intraoperative isolates? METHODS: A prospective study was conducted at two French reference centers that manage bone and joint infections and included 481 adult patients who had a revision or resection arthroplasty between June 25, 2012 and June 23, 2014. Exclusion criteria including no serum sample available for immunoassay, the lack of microbiological documentation, and the absence of preoperative aspiration reduced the patient number to 353. Seven patients with an undetermined SASA result were excluded from the analysis. We also excluded patients with PJI involving more than one Staphylococcus species (polystaphylococcal infection) and those in whom more than one Staphylococcus species was recovered from the preoperative synovial fluid culture (polystaphylococcal synovial fluid culture). In total, 340 patients were included in the analysis (no infection, 67% [226 of 340]; staphylococcal infection, 21% [71 of 340]; other infection, 13% [43 of 340]). The preoperative synovial fluid analysis included a cell count and differential and bacterial culture. SASAs were measured using a multiplex immunoassay. The diagnosis of PJI was determined using the Infectious Diseases Society of America (IDSA) criteria [] and intraoperative tissue culture at the time of revision surgery was used as the gold standard (at least one positive intraoperative sample for a "virulent" organism (such as S. aureus) or two positive samples for a "non-virulent" (for example S. epidermidis). RESULTS: SASA increased the PPV compared with synovial fluid culture alone (92% [95% CI 82 to 97] versus 79% [95% CI 68 to 87]; p = 0.04); when stratified by site, an increase in PPV was seen in hip infections (100% [95% CI 89 to 100] versus 77% [95% CI 63 to 88]; p = 0.01) but not in knee infections (84% [95% CI 66 to 95] versus 80% [95% CI 64 to 91]; p = 0.75). A positive cell count and differential result increased the PPV of staphylococcal synovial fluid cultures compared with synovial fluid culture alone (86% [95% CI 70 to 95] versus 79% [95% CI 68 to 87]; p = 0.36); when stratified by site, no difference in hip and knee infections was observed (86% [95% CI 67 to 96] versus 77% [95% CI 63 to 88]; p = 0.42) and 86% [95% CI 70 to 95] versus 80% [95% CI 64 to 91]; p = 0.74). CONCLUSION: SASA measurement improves the predictive value of synovial fluid cultures of the hip for all staphylococcal organisms, including coagulase-negative staphylococci, but the PPV of SASA plus synovial fluid culture it is not superior to the PPV of synovial fluid cell count/differential plus synovial culture for the knee. LEVEL OF EVIDENCE: Level III, diagnostic stud

Background The aims of this study were to identify the predictive factors for microbiological diagnosis through disco-vertebral biopsy (DVB) in patients with pyogenic vertebral osteomyelitis (PVO) and negative blood cultures, and compare the performance of DVB under fluoroscopic versus scanographic guidance. Methods We performed a cohort study comparing positive and negative DVB among patients with PVO. All cases of PVO undergoing a DVB for microbiological diagnosis in our center were retrospectively reviewed. Infections due to Mycobacterium tuberculosis, infections on foreign device, and non-septic diseases were excluded. Anamnestic, clinical, biological, microbiological, as well as radiological data were collected from medical charts thanks to a standardized data set. Results A total of 111 patients were screened; 88 patients were included. Microbiological cultures were positive in 53/88 (60.2%) patients. A thickening of the paravertebral tissue ≥10 mm on magnetic resonance imaging (MRI) in axial MR scans was a predictive factor of DVB microbiological positivity (52.4% vs. 13.3%; p = 0.006; OR = 5.4). Overall, 51 DVB were performed under fluoroscopic guidance and 37 under scanographic guidance. Considering lumbar DVB, 25/36 (69.4%) of cases yielded positive results under fluoroscopic guidance versus 5/15 (33.3%) under scanographic guidance (p = 0.02; OR = 4.4). No adverse event linked to DVB was notified. Conclusion Every patient with PVO and negative blood cultures should undergo a DVB. A thickening of the paravertebral tissue ≥10 mm on MRI is associated with a higher rate of positive DVB culture. A lumbar DVB under fluoroscopic guidance is more sensitive than under scanographic guidance to identify the micro-organism involved.

International audience; Potential of hydrogen (pH) is one of the most relevant parameters characterizing aqueous solutions. In biology, pH is intrinsically linked to cellular life since all metabolic pathways are implicated into ionic flows. In that way, determination of local pH offers a unique and major opportunity to increase our understanding of biological systems. Whereas the most common technique to obtain these data in analytical chemistry is to directly measure potential between two electrodes, in biological systems, this information has to be recovered in-situ without any physical interaction. Based on their non-invasive optical properties, fluorescent pH-sensitive probe are pertinent tools to develop. One of the most notorious pH-sensitive probes is fluorescein. In addition to excellent photophysical properties, this fluorophore presents a pH-sensitivity around neutral and physiologic domains. This review intends to shed new light on the recent use of fluorescein as pH-sensitive probes for biological applications, including targeted probes for specific imaging, flexible monitoring of bacterial growth, and biomedical applications.

International audience; Genome degradation has been central to the adaptation of Salmonella enterica serotypes to their hosts throughout evolution. We witnessed the patho-adaptation of a strain of Salmonella Dublin (a cattle-adapted serotype) to a human host during the course of a recurrent prosthetic hip joint infection evolving over several years.

FosA, a glutathione S-transferase that inactivates fosfomycin, has been reported as the cause of enzymatic resistance to fosfomycin. We show that multiple lineages of FosA-producing extended spectrum β-lactamase Escherichia coli have circulated in France since 2012, potentially reducing the efficacy of fosfomycin in treating infections with antimicrobial drug-resistant gram-negative bacilli.

The aim of this study was to describe the endotracheal respiratory flora in a population of adults suffering from neuromuscular or neurological disorders requiring a long-term tracheostomy and to identify risk factors for colonization. We conducted a prospective and single-center observational study among patients with chronic tracheostomy admitted for planned respiratory assessment between February 2015 and December 2016. Data were collected from patient interview and medical charts with a standardized questionnaire. A tracheal aspiration was performed for each patient. Humidifiers were analysed for bacteriological contamination. Overall 77 tracheal aspirates (TA) were obtained from patients included. Pathogenic bacteria were found in 90% of cases (69/77) with a majority of Pseudomonas aeruginosa (32/77, 41%), Staphylococcus aureus (34/77, 44%) and Serratia marcesens. (22/79, 38%) Amoxicillin + Clavulanic-acid and Cefotaxime were adapted for respectively in only 28% and 35% of the subjects due to the natural resistance of organisms. No pathogenic bacteria were isolated from humidifier samples. Risk factors significantly associated with P. aeruginosa colonization were residence in a medical-care home (p = 0.01, OR = 3.8 [1.1; 15.1]) and the presence of a cuff (p = 0.003, OR = 4.4 [1.1; 20.6]). Significant quantities of pathogenic bacteria are frequently isolated from TA of tracheostomised patients in the absence of infection. The frequent resistance of these pathogens to Amoxicillin + Clavulanic-acid precludes the use of this antibiotic in the empiric treatment of pneumonia in this population.

Cutibacterium acnes is a major etiologic agent of orthopaedic implant-associated infections (IAIs) and requires up to 14 days of incubation in an anaerobic atmosphere for growth detection. As blood culture (BC) systems are increasingly being used to monitor the growth of IAI specimens, we compared different BC media for growth detection of C. acnes. Non-duplicate C. acnes isolates (n = 99) obtained from sonicate-fluid cultures of orthopaedic IAIs from Slovenia (n = 54), conventional tissue samples of monomicrobial orthopaedic IAIs from France (n = 43) and two reference strains were inoculated to anaerobic BC bottles of two major BC systems and 3 conventional culture media types (thioglycolate broth, Schaedler and chocolate agar). Growth and time-to-detection (TTD) were recorded. Only Lytic (BACTEC) and SN (BacT/ALERT) bottles consistently detected growth of C. acnes within 14 days with 94% (n = 93) and 92% (n = 91) detection rates, respectively (p = 0.79). Lytic was superior to Plus BACTEC medium (p < 0.001), while SN was superior to all other BacT/ALERT media (p < 0.001). Mean TTD was 128 ± 43 h (61–336 h) for Lytic and 158 ± 65 h (77–336 h) for SN medium. Among the conventional media, 99% (n = 98) of the isolates grew on Schaedler agar, 96% (n = 95) in thioglycolate broth and 74% (n = 73) on chocolate agar. Inconsistent growth of C. acnes in different BC media can critically influence the detection of this major IAI pathogen. Only Lytic (BACTEC) and SN (BacT/ALERT) BC media types were consistently able to detect C. acnes within 14 days of incubation. However, visible growth was observed faster in thioglycolate broth and Schaedler agar media.

Introduction: Multiplex-antibody detection has been recently proposed for the noninvasive diagnosis of staphylococcal prosthetic joint infection (PJI). We evaluated this approach for the post-treatment follow-up of patients. Methods: Nineteen cases of staphylococcal PJI were prospectively followed for one year after treatment. The IgG response against eight staphylococcal antigens was measured before surgery and one year post-surgery using Luminex technology (Austin, TX, USA); median fluorescence intensity values determined for each antigen were transformed into a “Total Response Index” (TRI). Results: Patients (11 women/8 men) had a mean (SD) age of 72.2 (12.4) years. Site of prosthesis was the knee (n=10), the hip (n=8) and the shoulder (n=1). Ten patients were infected by S. epidermidis, six by S. aureus, and three by S. lugdunensis. TRI values at one year were significantly lower than pre-surgery values (mean [SD]: 5.9 [1.8] versus 8.1 [3.4], p=0.02) and decreased, on average, by 21.2%. TRI values markedly increased in two patients. One patient had a relapse of S. aureus PJI at five months post-surgery, with a 37% increase of the TRI. The other had septic failure three months after revision for S. lugdunensis PJI; all intraoperative samples remained culture-negative, but the TRI increased by 51% and the antibody profile showed a marked change, suggesting a reinfection with another staphylococcal species. Conclusion: Multiplex-antibody measurement may be useful for the follow-up of staphylococcal PJI and may help to detect septic failure involving organisms targeted by the assay.

Objectives Pressure ulcers are frequently observed in spinal cord injury (SCI) patients. They can be life-threatening and are a major medico-economic burden. Despite their frequency, their pathophysiology and optimal management are still poorly understood. Most available data comes from non-comparative studies, especially in terms of antimicrobial use. Methods We performed a critical review of the literature and opinions of infectious disease specialists based in a French expert center for this disease. We mainly focused on antimicrobial treatments prescribed in this situation. Results These infections are usually clinically diagnosed. Microbiological samples are not the gold standard for this assessment. Furthermore, reliable microbiological identification is a major challenge but should help select antimicrobial treatment. Imaging technique could be helpful but cannot replace the physical examination. The choice of antimicrobials must consider the potential ecological collateral damages in this vulnerable population. Antimicrobial therapy should be as short as possible, adapted to the microbiological identification, and must have suitable bioavailability. Conclusion Management of infected pressure ulcers is a major concern in disabled patients already highly exposed to antimicrobial treatment and multidrug-resistant organisms colonization. Extensive data is required.

Background Blood cultures, and molecular diagnostic tests that directly detect pathogen DNA in blood, fail to detect bloodstream infections in most infected patients. Thus, there is a need for a rapid test that can diagnose the presence of infection to triage patients, guide therapy, and decrease the incidence of sepsis. Methods An Enzyme-Linked Lectin-Sorbent Assay (ELLecSA) that uses magnetic microbeads coated with an engineered version of the human opsonin, Mannose Binding Lectin, containing the Fc immunoglobulin domain linked to its carbohydrate recognition domain (FcMBL) was developed to quantify pathogen-associated molecular patterns (PAMPs) in whole blood. This assay was tested in rats and pigs to explore whether it can detect infections and monitor disease progression, and in prospectively enrolled, emergency room patients with suspected sepsis. These results were also compared with data obtained from non-infected patients with or without traumatic injuries. Results The FcMBL ELLecSA was able to detect PAMPS present on, or released by, 85% of clinical isolates representing 47 of 55 different pathogen species, including the most common causes of sepsis. The PAMP assay rapidly ( 81%), specificity (> 89%), and diagnostic accuracy of 0·87. It also distinguished infection from trauma-related inflammation in the same patient cohorts with a higher specificity than the clinical sepsis biomarker, C-reactive Protein. Conclusion The FcMBL ELLecSA-based PAMP assay offers a rapid, simple, sensitive and specific method for diagnosing infections, even when blood cultures are negative and antibiotic therapy has been initiated. It may help to triage patients with suspected systemic infections, and serve as a companion diagnostic to guide administration of emerging dialysis-like sepsis therapies., Highlights • The FcMBL ELLecSA-based PAMP assay offers a rapid, simple, sensitive and specific method for diagnosing infections. • The FcMBL ELLecSA distinguished infection from trauma-related inflammation. • It can detect infection even when blood cultures are negative and antibiotic therapy has been initiated. Current diagnostics of sepsis using blood cultures and molecular diagnostic tests fail to detect bloodstream infections in most infected patients, whereas the inflammatory biomarkers of infection that have a higher sensitivity of detection, lack specificity in distinguishing infection from trauma-related inflammation. Therefore we have leveraged a broad-spectrum pathogen binding opsonin and developed a rapid test to directly diagnose the presence of infection in the blood to triage patients and guide antibiotic therapy.

We developed and evaluated a multiplex antibody detection-based immunoassay for the diagnosis of prosthetic joint infections (PJIs). Sixteen protein antigens from three Staphylococcus species ( Staphylococcus aureus , Staphylococcus epidermidis , and Staphylococcus lugdunensis ) (8 antigens), Streptococcus agalactiae (4 antigens), and Propionibacterium acnes (4 antigens) were selected by comparative immunoproteomics using serum samples from PJI cases versus controls. A bead-based multiplex immunoassay that measured serum IgG against purified, recombinant forms of each of the 16 antigens was developed. We conducted a prospective study to evaluate the performance of the assay. A PJI was defined by the presence of a sinus tract and/or positive intraoperative sample cultures (at least one sample yielding a virulent organism or at least two samples yielding the same organism). A total of 455 consecutive patients undergoing revision or resection arthroplasty (hip, 66.3%; knee, 29.7%; shoulder, 4%) at two French reference centers for the management of PJI were included: 176 patients (38.7%) were infected and 279 (61.3%) were not. About 60% of the infections involved at least one of the species targeted by the assay. The sensitivity/specificity values were 72.3%/80.7% for targeted staphylococci, 75%/92.6% for S. agalactiae , and 38.5%/84.8% for P. acnes . The assay was more sensitive for infections occurring >3 months after arthroplasty and for patients with an elevated C-reactive protein (CRP) or erythrocyte sedimentation rate (ESR). However, it detected 64.3% and 58.3% of targeted staphylococcal infections associated with normal CRP and ESR values, respectively. This new multiplex immunoassay approach is a novel noninvasive tool to evaluate patients suspected of having PJIs and provides information complementary to that from inflammatory marker values.

Cutibacterium acnes orthopedic device-related infections (ODRIs) range from obvious infections to solely culture-based diagnoses. Multilocus sequence typing of multiple isolates from the same procedure revealed that most cases with normal C-reactive protein levels that were classified as C. acnes ODRI would be considered contaminations when accounting for genotypic data.

Introduction Deux nouveaux antibiotiques associant une cephalosporine et un inhibiteur de betalactamase ont ete recemment mis sur le marche. Leur efficacite au cours des infections osteo-articulaires est mal connue. Materiels et methodes Etude retrospective monocentrique, de 05/2016 a 01/2019, des prescriptions de ceftolozane-tazobactam (C/T) et ceftazidime-avibactam (C/A) au cours des infections osteo-articulaire. Les patients ont ete identifies par la pharmacie et les dossiers medicaux revus avec une fiche standardisee de recueil incluant indication, caracteristiques cliniques, biologiques et microbiologiques, evolution, tolerance. Resultats Nous avons recense 10 prescriptions de C/T et 14 de C/A. L’âge median etait de 63,0 ans dans le groupe C/T et 64,0 ans (IQR 51,75–66,0) dans le groupe C/A (IQR 44,8–71,0), avec un sexe ratio (M/F) exclusivement masculin dans le groupe C/T et de 2,5 dans le groupe C/A. La duree d’hospitalisation etait de 48,0 jours dans le groupe C/T et de 95,5 jours dans le groupe C/A. Dans le groupe C/A, 13 patients ont beneficie d’une prise en charge medico-chirurgicale pour infection de prothese (3), arthrite (8), escarre avec osteite (3). Dans le groupe C/T, 9 patients ont beneficie d’une prise en charge medico-chirurgicale pour infection de materiel (2), arthrite (5), escarre (2), osteite (1). Les prelevements per-operatoires ont permis un diagnostic microbiologique dans 90 % des cas dans le groupe C/T et dans 92,9 % des cas dans le groupe C/A. Les prelevements etaient polymicrobiens dans 66 % des cas dans le groupe C/T et 85,7 % dans le groupe C/A. Le choix de l’antibiotherapie etait lie a la resistance microbiologique dans 80 % des cas dans le groupe C/T et dans 78,5 % des cas dans le groupe C/A. Dans le groupe C/A, les principales bacteries multiresistantes identifiees etaient : P.aeruginosa (5), K. pneumoniae BLSE (5), K.pneumoniae secretrice de carbapenemase (2), E.coli BLSE (2), E.cloacae BLSE (3), et A. baumanii (1). Dans le groupe C/T, il s’agissait de P. aeruginosa (7), K. pneumoniae BLSE (1), M.morganii (1), C. koseri (1). Dans le groupe C/A, l’evolution etait favorable pour 9 patients, 4 ont rechute et 1 est decede. Dans le groupe C/T, on note 7 guerisons, 2 rechutes et 1 deces. Une encephalopathie sous C/A a ete recensee. Conclusion Peu de donnees sont disponibles sur l’utilisation hors AMM de C/A et C/T dans les infections-osteo-articulaires. Notre experience recense des infections polymicrobiennes avec au moins un germe multi-resistant, principalement P.aeruginosa ou enterobacteries BLSE. Bien que s’agissant de patients multi-operes aux nombreuses comorbidites, l’utilisation de C/A et C/T a permis une reponse favorable lors de situations complexes.

We compared two walk-away molecular diagnostic assays, the GeneXpert MRSA Gen 3 assay and the BD-Max MRSA XT assay. A total of 119 prospective swabs and 36 culture-positive samples were tested. Xpert MRSA Gen 3 had sensitivity of 95.7% and specificity of 100% versus 87.5% and 97.1% for BD-Max. The difference in agreement with the enriched culture results was significantly in favor of the Xpert assay ( P < 0.02, McNemar nonparametric text).

Mycobacterium abscessus is a pathogenic, rapidly growing mycobacterium involved in pulmonary and cutaneo-mucous infections worldwide, to which cystic fibrosis patients are exquisitely susceptible. The analysis of the genome sequence of M. abscessus showed that this bacterium is endowed with the metabolic pathways typically found in environmental microorganisms that come into contact with soil, plants, and aquatic environments, where free-living amoebae are frequently present. M. abscessus also contains several genes that are characteristically found only in pathogenic bacteria. One of them is MAB_0555 , encoding a putative phospholipase C (PLC) that is absent from most other rapidly growing mycobacteria, including Mycobacterium chelonae and Mycobacterium smegmatis . Here, we report that purified recombinant M. abscessus PLC is highly cytotoxic to mouse macrophages, presumably due to hydrolysis of membrane phospholipids. We further showed by constructing and using an M. abscessus PLC knockout mutant that loss of PLC activity is deleterious to M. abscessus intracellular survival in amoebae. The importance of PLC is further supported by the fact that M. abscessus PLC was found to be expressed only in amoebae. Aerosol challenge of mice with M. abscessus strains that were precultured in amoebae enhanced M. abscessus lung infectivity relative to M. abscessus grown in broth culture. Our study underlines the importance of PLC for the virulence of M. abscessus . Despite the difficulties of isolating M. abscessus from environmental sources, our findings suggest that M. abscessus has evolved in close contact with environmental protozoa, which supports the argument that amoebae may contribute to the virulence of opportunistic mycobacteria.

Scedosporium apiospermum is a ubiquitous filamentous fungus, commonly found in soil, sewage and polluted waters. It is rarely pathogenic but can cause a broad spectrum of clinical diseases, which can be localised or disseminate to distant organs. The disseminated form of the disease is mostly seen among immunocompromised patients. However, some rare cases of disseminated disease have been reported in immunocompetent individuals. Treatment of these infections is challenging because of their natural resistance to many antifungal agents. Here, we report the case of a 57-year-old immunocompetent patient diagnosed with femoral pseudarthrosis due to S. apiospermum, despite having no obvious clinical sign of infection. Previously, the patient had undergone four iterative femoral surgeries following a road traffic accident which occurred 20 years before. During its last surgery for pseudarthrosis, no clinical or biological signs of infection were present. Per operative samples tested positive for S. apiospermum. The patient was successfully treated with oral voriconazole during 6 months with an excellent tolerance. We also provide a review of literature on bone and joint infections due to Scedosporium spp. (S. apiospermum, Scedosporium boydii and Scedosporium aurantiacum), discussing the evolution of their management and outcome which seems to improve since the use of voriconazole.

We have read with great interest the report by Marshall et al. regarding the efficacy of the combination of ceftazidime-avibactam (CAZ-AVI) and aztreonam (ATM) against metallo-β-lactamase-producing Enterobacteriaceae ([1][1]). These results confirm our experience with two patients treated with CAZ

Perforations of surgical gloves are common and increase with the duration of glove wear. Skin flora, re-grown after pre-operative disinfection of the hands, may contaminate a surgical site. An antimicrobial surgical glove with chlorhexidine on its inner surface has been developed. We hypothesized that by suppressing the re-growth of skin flora during the complete course of a surgical procedure, antimicrobial gloves may reduce the risk of surgical site contamination in the event of an intra-operative glove breach.We conducted a randomized, double-blind, single-center trial, to measure any differences in the bacterial skin populations of surgeons' hands during surgical procedures done with antimicrobial and non-antimicrobial surgical gloves [ISRCTN71391952]. In this study, 25 pairs of gloves were retrieved from 14 surgeons who donned them randomly on their dominant or non-dominant hand. The number of bacteria retrieved from glove fluid was measured and expressed as colony forming units (CFU)/mL.The median cfu/mL of antimicrobial gloves was 0.00 (LQ: 0.00 CFU/mL; UQ: 0.00 cfu/mL), with a mean log10 cfu/mL=0.02 (range: 0.00-0.30). The median CFU/mL of non-antimicrobial gloves was 54.00 (LQ: 3.00 cfu/mL; UQ: 100.00 cfu/mL) with a mean log10 CFU/mL=1.32 (range: 0.00-2.39). After a mean operating time of 112 min, the difference in the log10 CFU/mL was 1.30 (p0.001).A new antimicrobial surgical glove suppressed surgeons' hand flora during operative procedures. In the event of a glove breach, the use of such a glove may have the potential to prevent bacterial contamination of a sterile surgical site, thereby decreasing the risk of surgical site infection (SSI) and increasing patient safety. Further clinical studies are needed to confirm this concept.

Background The bacterial colonization of urinary catheters is a major source of hospital acquired urinary tract infections (HAUTI). Bacteria repellent coatings could lower HAUTI prevalence and minimize antimicrobial usage. We report a model of spontaneous bacterial colonization of an intravesical catheter in a spinalized rat model, and the first in vivo proof of the efficacy of lubricant-infused catheters (LICs) in preventing bacterial colonization. Methods LICs preparation: Oxygen plasma treated polyethylene catheters were immediately placed in a vacuum desiccator and 200 µL of trichloro (1 hour,1H,2H,2H-perfluorooctyl) silane) was placed beside the catheter segments. The vacuum pump connected to the desiccator was turned on with the exit valve closed once a pressure of −0.08 MPa was achieved. The chemical vapour deposition process was initiated for 4 hours. Catheters were removed from the desiccator and placed in an oven at 60oC for a minimum of 12 hours in order to complete the modification process. Catheters were saturated with a biocompatible fluorocarbon-based lubricant (perfluorodecalin) prior to implantation. Thirty centimeters long native catheters and LICs were surgically implanted in the bladder of rats spinalized 19 days prior and programmed to undergo cystometry experiments 48 hours later. Each rat was maintained individually in a cage with food and water ad libitum until bladder functional evaluation, and benefitted from a of trimethoprim sulfadoxine and fluoroquinolone prophylaxis. At the end of the cystometry experiments, the animals were euthanized and the bladder catheter was removed. A 1 cm section from the intravesical end of the catheter was cut and placed in 1 mL of Amies medium (eSawb, Copan), vortexed and sonicated. Ten microliters of the suspension were plated on URIselect4 medium (Bio-Rad, Hercules, Ca) for bacterial enumeration. Results A significant reduction in bacterial colonization with Enterobacteriaceae and Enterococci was observed in the LICs group (N = 6, below 100 CFU threshold) compared with the native catheter group (N = 5, average 8200 CFU) (P < 0.02). Conclusion Lubricant-infused catheters effectively prevent bacterial colonization in vivo and provide an attractive and nonselective option for HAUTI prevention. Disclosures All authors: No reported disclosures.

Introduction Au cours de la prise en charge en 2 temps des infections sur prothese osteoarticulaires (IPOA), lors de la repose, une antibiotherapie postoperatoire large spectre probabiliste est systematiquement prescrite en raison du possible risque de sepsis persistant. Elle est debutee apres realisation des prelevements a visee microbiologiques peroperatoires et arretee en cas de negativite ; ce qui est frequemment le cas. Un test de detection rapide (15 minutes) de l’α-defensine permettant de detecter les IPOA a ete recemment commercialise et ses resultats semblent prometteurs en cas de suspicion d’infection. Nous nous sommes interesses a sa performance lors des reposes au cours de prise en charge en 2 temps. Il pourrait alors permettre d’eviter une exposition antibiotique large spectre inutile. Materiels et methodes Etude prospective monocentrique de 16 cas de repose de prothese osteoarticulaires post-episode septique ne presentant pas de signe clinique ni biologique d’infection lors du geste. Un test de detection de l’α-defensine a ete realise en extemporane sur le liquide articulaire en peroperatoire avant administration d’antibiotique et en meme temps que les prelevements a visee microbiologique. Nous avons compare les resultats du test d’α-defensine et les cultures microbiologiques prolongees en milieu enrichi apres broyage comme realise dans notre centre. Resultats Au total, 16 patients ont ete inclus, l’âge moyen etait de 67,1 ans (range 43–80), le sex-ratio etait de 1,00. Deux patients etaient immunodeprimes. Il s’agissait de 9 cas de protheses de genou, 4 de hanche, 2 de cheville, et 1 d’epaule. Le nombre moyen d’interventions prealables etait de 2,4. Les bacteries identifiees lors du precedent episode septique etaient : Escherichia coli (n = 2), SAMS (n = 2), SARM (n = 1), staphylocoques a coagulase negative (n = 7) (Staphylococcus warneri, S. lugdunensis, S. haemolyticus, S. simulans, S. schleferi, S. epidermidis meti-R et S. caprae), streptocoques (n = 2), enterocoques (n = 2), anaerobes (n = 1), et Candida sp. (n = 1). Au moment de la reprise les patients etaient apyretiques, il n’existait pas de signe locaux et/ou generaux de sepsis. La CRP moyenne etait de 39,7 mg/L et le taux moyen de leucocytes de 9,6 G/L. Au total, l’α-defensine etait negative dans tous les cas, ainsi que les prelevements microbiologiques. Conclusion L’α-defensine semble un outil interessant pour dedouaner la persistance d’une infection dans le cas de repose de prothese osteoarticulaire et permettrait d’eviter d’exposer inutilement les patients a une antibiotherapie intempestive. Cette indication originale doit etre validee par des etudes de plus large ampleur.