Complement activation drives the phagocytosis of necrotic cell debris and resolution of liver injury.

Cells die by necrosis due to excessive chemical or thermal stress, leading to plasma membrane rupture, release of intracellular components and severe inflammation. The clearance of necrotic cell debris is crucial for tissue recovery and injury resolution, however, the underlying mechanisms are still poorly understood, especially . This study examined the role of complement proteins in promoting clearance of necrotic cell debris by leukocytes and their influence on liver regeneration.

Early detection of OXA-48 producing Klebsiella pneumoniae with the use of rapid antibiotic susceptibility testing.

Rapid antimicrobial susceptibility testing of positive blood cultures can enhance antimicrobial stewardship and patient outcomes. We present a case where OXA-48-producing Klebsiella pneumoniae with low-level carbapenem resistance was suspected 6 h after blood-culture positivity, based on ASTar system (Q-Linea, Sweden) results. OXA-48 carbapenemase presence was confirmed by the OXA-48 K-SeT lateral flow assay (Coris, Belgium) on a short-term subculture.

A novel synthetic synovial fluid model for investigating biofilm formation and antibiotic susceptibility in prosthetic joint infections.

Unlabelled: There is growing evidence that bacteria encountered in prosthetic joint infections (PJIs) form surface-attached biofilms on prostheses, as well as biofilm aggregates embedded in synovial fluid and tissues. However, models allowing the investigation of these biofilms and the assessment of their antimicrobial susceptibility in physiologically relevant conditions are currently lacking. To address this, we developed a synthetic synovial fluid (SSF2) model and validated this model by investigating growth, aggregate formation, and antimicrobial susceptibility using multiple PJI isolates belonging to various microorganisms.

Validation of EUCAST rapid antimicrobial susceptibility testing directly from positive blood cultures in a non-automated lab setting.

Introduction: To speed up antimicrobial susceptibility testing (AST), the European Committee on Antimicrobial Susceptibility Testing (EUCAST) proposed rapid AST (RAST), a disk diffusion method to be read after 4, 6 and 8 hours of incubation. We investigated the feasibility of implementation of RAST in a non-automated lab setting.

Materials & Methods: To this end, reference strains as well as a variety of clinical and resistant strains were used to spike sterile hemocultures (BioMérieux BACT/ALERT 3D® and Becton Dickinson BACTEC FX® systems), followed by RAST in comparison to classical long-incubation AST.

Expansion of MALDI-TOF MS database as a strategy for identification of species other than .

Objectives: This study aimed to evaluate an expanded matrix-assisted laser desorption-ionization-time of flight mass spectrometry (MALDI-TOF MS) database for the identification of species other than (Hi).

Methods: A total of 144 species, cultured from respiratory samples from people (living) with cystic fibrosis, were identified with MALDI-TOF MS and 16S rRNA sequencing. Of these, 99 strains showed >99% similarity with the best matching strain in the National Center for Biotechnology Information (NCBI) database and were assigned to a single subspecies using both MALDI-TOF MS and 16S rRNA sequencing.

The immunology of B-1 cells: from development to aging.

B-1 cells have intricate biology, with distinct function, phenotype and developmental origin from conventional B cells. They generate a B cell receptor with conserved germline characteristics and biased V(D)J recombination, allowing this innate-like lymphocyte to spontaneously produce self-reactive natural antibodies (NAbs) and become activated by immune stimuli in a T cell-independent manner. NAbs were suggested as "rheostats" for the chronic diseases in advanced age.

Spiroplasma infection as a cause of severe congenital keratouveitis, cataract and glaucoma.

Background: Only seven cases of ocular Spiroplasma infection have been reported to date, all presenting as congenital cataracts with concomitant intraocular inflammation. We describe the first case of Spiroplasma infection initially presenting as a corneal infiltrate.

Case Presentation: A 1-month-old girl was referred for a corneal infiltrate in the left eye.

Natural antibodies are required for clearance of necrotic cells and recovery from acute liver injury.

Background & Aims: Hepatocellular necrosis is common in both acute and chronic liver injury and may evolve to fibrosis and liver failure. Injury leads to accumulation of necrotic cell debris in the liver, which drives persistent inflammation and poor recovery. This study investigated the role of natural antibodies (NAbs) in the clearance of necrotic cells in the injured liver, their impact on tissue regeneration and their potential as a therapy for acute liver injury.

The use of information technology to improve interdisciplinary communication during infectious diseases ward rounds on the paediatric intensive care unit.

Prospective audit with feedback during infectious diseases ward rounds (IDWR) is a common antimicrobial stewardship (AMS) practice on the Paediatric Intensive Care Unit (PICU). These interdisciplinary meetings rely on the quality of handover, with high risk of omission of information. We developed an electronic platform integrating infection-related patient data (COSARAPed).

Sanitary installations and wastewater plumbing as reservoir for the long-term circulation and transmission of carbapenemase producing Citrobacter freundii clones in a hospital setting.

Background: Accumulating evidence shows a role of the hospital wastewater system in the spread of multidrug-resistant organisms, such as carbapenemase producing Enterobacterales (CPE). Several sequential outbreaks of CPE on the geriatric ward of the Ghent University hospital have led to an outbreak investigation. Focusing on OXA-48 producing Citrobacter freundii, the most prevalent species, we aimed to track clonal relatedness using whole genome sequencing (WGS).

EUCAST rapid antimicrobial susceptibility testing (RAST) compared to conventional susceptibility testing: implementation and potential added value in a tertiary hospital in Belgium.

Objectives: EUCAST breakpoints for short incubation disk diffusion allow rapid antimicrobial susceptibility testing (RAST) directly from positive blood cultures. We evaluate the RAST methodology and assess its potential added value in a setting of low prevalence of multidrug-resistant (MDR) organisms.

Methods: In our two-part study, we performed RAST on 127 clinical blood cultures at 6 and 8 h and determined categorical agreement with direct susceptibility testing.

The GAG-Binding Peptide MIG30 Protects against Liver Ischemia-Reperfusion in Mice.

Ischemia-reperfusion injury (IRI) drives graft rejection and is the main cause of mortality after liver transplantation. During IRI, an intense inflammatory response marked by chemokine production and neutrophil recruitment occurs. However, few strategies are available to restrain this excessive response.

Lower persistence of anti-nucleocapsid compared to anti-spike antibodies up to one year after SARS-CoV-2 infection.

We retrospectively compared the long-term evolution of IgG anti-spike (S) and anti-nucleocapsid (N) levels (Abbott immunoassays) in 116 non-severe and 115 severe SARS-CoV-2 infected patients from 2 university hospitals up to 365 days post positive RT-PCR. IgG anti-S and anti-N antibody levels decayed exponentially up to 365 days after a peak 0 to 59 days after positive RT-PCR. Peak antibody level/cut-off ratio 0 to 59 days after positive RT-PCR was more than 70 for anti-S compared to less than 6 for anti-N (P < 0.

Effects of cascade reporting of susceptibility profiles for Enterobacterales on broad-spectrum antibiotics use and resistance.

Objective: To reduce the inappropriate use of broad-spectrum antibiotics in a 1000+ bed acute tertiary care hospital by the introduction of cascade antimicrobial susceptibility reporting for Enterobacterales.

Methods: Over a 1-year period, we selectively suppressed reporting of susceptibility to the broad-spectrum antibiotics piperacillin-tazobactam (TZP) and meropenem (MEM) for Enterobacterales strains susceptible to amoxicillin-clavulanic acid (AMC) and negative for extended-spectrum β-lactamase (ESBL). We measured the effects on hospital-wide antibiotic consumption (defined daily doses/1000 admissions) and resistance of and on two levels.

Impact of the introduction of EUCAST's concept of "area of technical uncertainty".

On the first of January 2019, the European Committee on Antimicrobial Susceptibility Testing, EUCAST, introduced the concept of "area of technical uncertainty" (ATU). The aim was to report on the incidence of ATU test results in a selection of common bacterial species and the subsequent impact on antimicrobial resistance categorization and workload. A retrospective analysis of clinical samples collected from February 2019 until November 2019 was performed.

Inhibition of Drug-Induced Liver Injury in Mice Using a Positively Charged Peptide That Binds DNA.

Hepatic cell death occurs in response to diverse stimuli such as chemical and physical damage. The exposure of intracellular contents such as DNA during necrosis induces a severe inflammatory response that has yet to be fully explored therapeutically. Here, we sought means to neutralize the ability of extracellular DNA to induce deleterious tissue inflammation when drug-induced liver injury had already ensued.

Different long-term avidity maturation for IgG anti-spike and anti-nucleocapsid SARS-CoV-2 in hospitalized COVID-19 patients.

Introduction: The high variability of SARS-CoV-2 serological response after COVID-19 infection hampers its use as indicator of the timing of infection. A potential alternative method is the determination of affinity maturation of SARS-CoV-2 IgG, expressed as the SARS-CoV-2 IgG avidity.

Methods: SARS-CoV-2 IgG concentration and avidity were measured in sera of hospitalized COVID-19 patients sampled at two weeks and ≥12 weeks post symptom onset using an in-house developed protocol based on EUROIMMUN (anti-spike) and EDI™ (anti-nucleocapsid) SARS-CoV-2 IgG ELISA protocols.

Complement Receptors and Their Role in Leukocyte Recruitment and Phagocytosis.

The complement system is deeply embedded in our physiology and immunity. Complement activation generates a multitude of molecules that converge simultaneously on the opsonization of a target for phagocytosis and activation of the immune system via soluble anaphylatoxins. This response is used to control microorganisms and to remove dead cells, but also plays a major role in stimulating the adaptive immune response and the regeneration of injured tissues.

Longitudinal follow-up of IgG anti-nucleocapsid antibodies in SARS-CoV-2 infected patients up to eight months after infection.

Background: Most SARS-CoV-2 infected patients develop IgG antibodies within 2-3 weeks after symptom onset. Antibody levels have been shown to gradually decrease in the first months after infection, but few data are available at six months or later.

Methods: A retrospective multi-center study was performed using 652 samples of 236 PCR-confirmed SARS-CoV-2 infected patients from 2 Belgian University hospitals.

Diagnosing COVID-19; towards a feasible COVID-19 rule-out protocol.

Introduction: We present the results of the COVID-19 rule-out protocol at Ghent University Hospital, a step-wise testing approach which included repeat NFS SARS-CoV-2 rRT-PCR, respiratory multiplex RT-PCR, low-dose chest CT and bronchoscopy with BAL to confirm or rule-out SARS-CoV-2 infection in patients admitted with symptoms suggestive of COVID-19.

Results: Between 19 March 2020 and 30 April 2020, 455 non-critically ill patients with symptoms suspect for COVID-19 were admitted. The initial NFS for SARS-CoV-2 rRT-PCR yielded 66.

Combined oropharyngeal/nasal swab is equivalent to nasopharyngeal sampling for SARS-CoV-2 diagnostic PCR.

Background: Early 2020, a COVID-19 epidemic became a public health emergency of international concern. To address this pandemic broad testing with an easy, comfortable and reliable testing method is of utmost concern. Nasopharyngeal (NP) swab sampling is the reference method though hampered by international supply shortages.

Sensitivity and specificity of 14 SARS-CoV-2 serological assays and their diagnostic potential in RT-PCR negative COVID-19 infections.

Background: Molecular detection of SARS-CoV-2 in respiratory samples is the gold standard for COVID-19 diagnosis but it has a long turnaround time and struggles to detect low viral loads. Serology could help to diagnose suspected cases which lack molecular confirmation. Two case reports are presented as illustration.

Synovial Fluid Neutrophils From Patients With Juvenile Idiopathic Arthritis Display a Hyperactivated Phenotype.

Objective: Juvenile idiopathic arthritis (JIA) is the most common rheumatic disease in childhood. The predominant subtypes, oligoarticular and polyarticular JIA, are traditionally considered to be autoimmune diseases with a central role for T cells and autoantibodies. Mounting evidence suggests an important role for neutrophils in JIA pathogenesis.