A retrospective propensity-score-matched cohort study of the impact of procalcitonin testing on antibiotic use in hospitalized patients during the first wave of COVID-19.

Background: Procalcitonin (PCT) is a blood marker used to help diagnose bacterial infections and guide antibiotic treatment. PCT testing was widely used/adopted during the COVID-19 pandemic in the UK.

Objectives: Primary: to measure the difference in length of early (during first 7 days) antibiotic prescribing between patients with COVID-19 who did/did not have baseline PCT testing during the first wave of the pandemic.

Low circulating B cells in immunocompromised individuals are linked to poorer antibody responses to vaccines and a predisposition to viral infections.

Background: B cells play an important role in protection against viral infections, not only through the production of antibodies but also through their ability to act as antigen-presenting cells and produce cytokines.

Objectives: To assess whether there is a link between low circulating B-cell counts and a predisposition to viral infections in immunocompromised individuals, we performed a retrospective cohort analysis at 2 National Health Service Clinical Immunology sites in England.

Methods: Eligible patients were adults who were either diagnosed with or under investigation for an immunodeficiency and had recorded circulating B-cell counts.

Antibacterial effect of seven days exposure to ceftolozane-tazobactam as monotherapy and in combination with fosfomycin or tobramycin against Pseudomonas aeruginosa with ceftolozane-tazobactam MICs at or above 4 mg/l in an in vitro pharmacokinetic model.

Objectives: To use a pre-clinical pharmacokinetic infection model to assess the antibacterial effect of ceftolozane/tazobactam alone or in combination with fosfomycin or tobramycin against Pseudomonas aeruginosa strains with MICs at or higher than the clinical breakpoint (MIC ≥ 4 mg/L).

Methods: An in vitro model was used to assess changes in bacterial load and population profiles after exposure to mean human serum concentrations of ceftolozane/tazobactam associated with doses of 2 g/1 g q8h, fosfomycin concentrations associated with doses of 8 g q8h or tobramycin at doses of 7 mg/kg q24 h over 168 h.

Results: Simulations of ceftolozane/tazobactam at 2 g/1 g q8h alone produced 3.

Procalcitonin Evaluation of Antibiotic Use in COVID-19 Hospitalised Patients (PEACH): Protocol for a Retrospective Observational Study.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a novel virus responsible for the coronavirus disease 2019 (COVID-19) pandemic. Although COVID-19 is a viral illness, many patients admitted to hospital are prescribed antibiotics, based on concerns that COVID-19 patients may experience secondary bacterial infections, and the assumption that they may respond well to antibiotic therapy. This has led to an increase in antibiotic use for some hospitalised patients at a time when accumulating antibiotic resistance is a major global threat to health.

Diagnostic MALDI-TOF MS can differentiate between high and low toxic bacteraemia isolates as a predictor of patient outcome.

bacteraemia (SAB) is a major cause of blood-stream infection (BSI) in both healthcare and community settings. While the underlying comorbidities of a patient significantly contributes to their susceptibility to and outcome following SAB, recent studies show the importance of the level of cytolytic toxin production by the infecting bacterium. In this study we demonstrate that this cytotoxicity can be determined directly from the diagnostic MALDI-TOF mass spectrum generated in a routine diagnostic laboratory.

Comparative bactericidal activity of representative β-lactams against Enterobacterales, Acinetobacter baumannii and Pseudomonas aeruginosa.

Background: There is surprisingly little comparative published data on the bactericidal action of different sub-classes of β-lactams against aerobic Gram-negative rods, and the assumption is that all behave in the same way.

Objectives: To describe a systematic investigation of a representative penicillin, cephalosporin, monobactam and carbapenem against Escherichia coli, Klebsiella pneumoniae, Acinetobacter baumannii and Pseudomonas aeruginosa.

Methods: Concentration-time-kill curves (TKC) were determined for three strains each of E.

Are multiple-use bottles of chlorhexidine solutions at risk of contamination in joint replacement surgery?

Introduction: Chlorhexidine gluconate 2% w/v in isopropanol 70% solutions in multiple-use bottles is commonly used in surgery as a cost-effective method for skin disinfection. However, multiple-use bottles risk contamination. This study aims to test whether bacterial contamination of multiple-use bottles or their solutions occurs once open and on use between different patients.

Long-term nitrofurantoin: an analysis of complication awareness, monitoring, and pulmonary injury cases.

Background: Long-term nitrofurantoin (NF) treatment can result in pulmonary and hepatic injury. Current guidelines do not outline the type or frequency of monitoring required for detection of these injuries.

Aim: To assess 1) awareness of NF complications among prescribers; 2) monitoring practice; and 3) to describe the pulmonary sequelae of NF-related complications.

Consensus-based antimicrobial resistance and stewardship competencies for UK undergraduate medical students.

Background: In the UK there is limited coverage of antimicrobial stewardship across postgraduate curricula and evidence that final year medical students have insufficient and inconsistent antimicrobial stewardship teaching. A national undergraduate curriculum for antimicrobial resistance and stewardship is required to standardize an adequate level of understanding for all future doctors.

Objectives: To provide a UK national consensus on competencies for antimicrobial resistance and stewardship for undergraduate medical education.

Use of Procalcitonin during the First Wave of COVID-19 in the Acute NHS Hospitals: A Retrospective Observational Study.

A minority of patients presenting to hospital with COVID-19 have bacterial co-infection. Procalcitonin testing may help identify patients for whom antibiotics should be prescribed or withheld. This study describes the use of procalcitonin in English and Welsh hospitals during the first wave of the COVID-19 pandemic.

Trade-Offs between Antibacterial Resistance and Fitness Cost in the Production of Metallo-β-Lactamases by Enteric Bacteria Manifest as Sporadic Emergence of Carbapenem Resistance in a Clinical Setting.

Meropenem is a clinically important antibacterial reserved for treatment of multiresistant infections. In meropenem-resistant bacteria of the family , NDM-1 is considerably more common than IMP-1, despite both metallo-β-lactamases (MBLs) hydrolyzing meropenem with almost identical kinetics. We show that consistently confers meropenem resistance in wild-type , but does not.

Post-acute COVID-19 associated with evidence of bystander T-cell activation and a recurring antibiotic-resistant bacterial pneumonia.

Here, we describe the case of a COVID-19 patient who developed recurring ventilator-associated pneumonia caused by that acquired increasing levels of antimicrobial resistance (AMR) in response to treatment. Metagenomic analysis revealed the AMR genotype, while immunological analysis revealed massive and escalating levels of T-cell activation. These were both SARS-CoV-2 and specific, and bystander activated, which may have contributed to this patient's persistent symptoms and radiological changes.

Population Pharmacokinetics of Intraventricular Vancomycin in Neonatal Ventriculitis, A Preterm Pilot Study.

Aim: Intraventricular vancomycin is an effective treatment for neonatal ventriculitis, as the cerebrospinal fluid (CSF) vancomycin levels reach adequate concentrations to achieve microbiological cure. There is no robust data on intraventricular vancomycin pharmacokinetics in the preterm population. This pilot population pharmacokinetic modelling study examines the pharmacokinetic behaviour of intraventricular vancomycin in the preterm population of < 28 weeks gestation, to inform the feasibility of future prospective studies.

Procalcitonin in respiratory disease: use as a biomarker for diagnosis and guiding antibiotic therapy.

Unlabelled: Procalcitonin (PCT) is a peptide measurable in serum which becomes elevated in response to bacterial infection. Multiple trials have explored the safety and efficacy of using PCT as a biomarker to guide decisions about starting or stopping antibiotic therapy in a wide variety of situations, and PCT assays have recently been approved by the Federal Drug Administration (FDA) in the US for use in both sepsis and respiratory tract infections. While there have been a number of promising results particularly in acute respiratory tract infections and intensive care unit settings, problems including adherence to protocol, cost of the assay and improved antimicrobial stewardship more generally, have limited more widespread adoption.

Using artificial intelligence to reduce diagnostic workload without compromising detection of urinary tract infections.

Background: A substantial proportion of microbiological screening in diagnostic laboratories is due to suspected urinary tract infections (UTIs), yet approximately two thirds of urine samples typically yield negative culture results. By reducing the number of query samples to be cultured and enabling diagnostic services to concentrate on those in which there are true microbial infections, a significant improvement in efficiency of the service is possible.

Methodology: Screening process for urine samples prior to culture was modelled in a single clinical microbiology laboratory covering three hospitals and community services across Bristol and Bath, UK.

Early Warning Scores do not accurately predict mortality in sepsis: A meta-analysis and systematic review of the literature.

Objectives: Early Warning Scores are used to evaluate patients in many hospital settings. It is not clear if these are accurate in predicting mortality in sepsis. We performed a systematic review and meta-analysis of multiple studies in sepsis.

Successful treatment of multicompartmental cerebral ventriculitis caused by .

We present a case report of a 58-year- old woman with subarachnoid haemorrhage complicated by non-communicating hydrocephalus. During the course of her neurosurgical management, she developed external-ventricular drain associated ventriculitis which in turn was complicated by lack of communication between third and fourth ventricles. The causative organism was a fully-sensitive , a nosocomial pathogen often associated with complicated treatment regimens and poor outcomes.