Simultaneous clonal spread of NDM-1-producing ST773 from Ukrainian patients in the Netherlands and Spain.

Objectives: We describe the clonal spread of New Delhi metallo-β-lactamase (NDM) 1-producing isolates belonging to the ST773 clone in Spain and the Netherlands, associated with the transfer of Ukrainian patients during the war.

Methods: Between March and December 2022, nine NDM-1-producing ST773 isolates were recovered from nine Ukrainian patients evacuated to two Spanish ( = 3) and five Dutch ( = 6) hospitals. Antimicrobial susceptibility testing was studied (Sensititre, Microscan, EUCAST-2023).

Rapid screening of SARS-CoV-2 variants, a key tool for pandemic surveillance.

The utility of reverse transcription-polymerase chain reaction (RT-PCR) in analysis SARS-COV-2 variants was evaluated. RT-PCR tests were used to analyse the majority of new SARS-CoV-2 cases (n = 9315) in a tertiary hospital (Madrid, Spain) throughout 2021. Subsequently, whole genome sequencing (WGS) was conducted on 10.

Carbapenemase-Producing in COVID-19 Intensive Care Patients: Identification of IncL-VIM-1 Plasmid in Previously Non-Predominant Sequence Types.

During the COVID-19 pandemic, intensive care units (ICUs) operated at or above capacity, and the number of ICU patients coinfected by nosocomial microorganisms increased. Here, we characterize the population structure and resistance mechanisms of carbapenemase-producing (CP-Kpn) from COVID-19 ICU patients and compare them to pre-pandemic populations of CP-Kpn. We analyzed 84 CP-Kpn isolates obtained during the pandemic and 74 CP-Kpn isolates obtained during the pre-pandemic period (2019) by whole genome sequencing, core genome multilocus sequence typing, plasmid reconstruction, and antibiotic susceptibility tests.

First confirmation of importation and transmission in Spain of the newly identified SARS-CoV-2 B.1.1.7 variant.

Introduction: A newly identified SARS-CoV-2 variant, VOC202012/01 originating lineage B.1.1.

Risk Factors and Outcomes for Multidrug Resistant Infection in Immunocompromised Patients.

Background: Pseudomonas aeruginosa (PSA) infection often occurs in immunocompromised patients, which also face an increased risk of multidrug-resistant (MDR) bacteria. A deeper knowledge of the risk factors for MDR-PSA infection in this patient population may help to choose appropriate empirical antibiotic therapy. Methods: a single-center case-control (1:2) retrospective study that included 48 patients with underlying immunosuppression developing MDR-PSA infection (cases) and 96 patients also immunocompromised that were infected with non-MDR-PSA (controls) was conducted.

Strain-to-strain variability among Staphylococcus aureus causing prosthetic joint infection drives heterogeneity in response to levofloxacin and rifampicin.

Introduction: Levofloxacin and rifampicin are the preferred treatment for prosthetic joint infection (PJI) caused by Staphylococcus aureus, especially when managed with implant retention (DAIR). However, a significant variability of success has been reported, which could be related to intrinsic characteristics of the microorganism. Our aim was to evaluate the variability in the anti-biofilm response to levofloxacin and rifampicin in a clinical collection of S.

Microbiological and Molecular Features Associated with Persistent and Relapsing Prosthetic Joint Infection.

Background: Persistent and relapsing prosthetic joint infection (PJI) due to presents a clinical challenge. This study aimed to provide an extensive description of phenotypic and genomic changes that could be related to persistence or relapse.

Methods: Initial and second isolates from 6 cases of persistent and relapsing PJI, along with clinical isolates from 8 cases, with favorable outcome were included.

Genomic Analysis of Ceftazidime/Avibactam-Resistant GES-Producing Sequence Type 235 Isolates.

The emergence of ceftazidime/avibactam (CZA) resistance among Guiana extended-spectrum -lactamase (GES)-producing isolates has rarely been described. Herein, we analyze the phenotypic and genomic characterization of CZA resistance in different GES-producing isolates that emerged in our institution. A subset of nine CZA-resistant isolates was analyzed and compared with thirteen CZA-susceptible isolates by whole-genome sequencing (WGS).

Clinical impact of time-to-positivity of blood cultures on mortality in patients with Pseudomonas aeruginosa bacteremia.

Objectives: To investigate the impact of the time-to-positivity of blood cultures (TTP) on 30-day mortality in patients with Pseudomonas aeruginosa bacteremia.

Methods: All nonduplicated episodes of P. aeruginosa monomicrobial bacteremia in adult patients from January 2013 to February 2020 were analysed.

Dissemination of a single ST11 clone of OXA-48-producing within a large polyclonal hospital outbreak determined by genomic sequencing.

The population structure of a set of OXA-48-producing isolates belonging to sequence type 11 (ST11 Kp-OXA) and obtained from two hospitals in Madrid in the period from 2012 to 2015 was studied by genome sequencing. Overall, 97 ST11 Kp-OXA isolates were sequenced and their population structure and demography were studied by Bayesian phylodynamic analysis using core-genome SNVs. In total, 92 isolates were from Hospital La Paz, 57 of them from two selected units.

Derivation of a score to predict infection due to multidrug-resistant Pseudomonas aeruginosa: a tool for guiding empirical antibiotic treatment.

Objectives: Multidrug-resistant Pseudomonas aeruginosa (MDR-PSA) constitutes an emerging health problem. A predictive score of MDR-PSA infection would allow an early adaptation of empirical antibiotic therapy.

Methods: We performed a single-centre case-control (1:2) retrospective study including 100 patients with MDR-PSA and 200 with a non-MDR-PSA infection.

Clinical and bacterial characteristics of Pseudomonas aeruginosa affecting the outcome of patients with bacteraemic pneumonia.

Few studies have assessed the clinical and bacterial characteristics of Pseudomonas aeruginosa (PA) bacteraemic pneumonia (BP) episodes. This study analysed all non-duplicate PA-BP episodes from a tertiary hospital in 2013-2017. Epidemiology, clinical data, antimicrobial therapy and outcomes were recorded.

First confirmation of importation and transmission in Spain of the newly identified SARS-CoV-2 B.1.1.7 variant.

Introduction: A newly identified SARS-CoV-2 variant, VOC202012/01 originating lineage B.1.1.

Genomic Epidemiology of SARS-CoV-2 in Madrid, Spain, during the First Wave of the Pandemic: Fast Spread and Early Dominance by D614G Variants.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was first detected in Madrid, Spain, on 25 February 2020. It increased in frequency very fast and by the end of May more than 70,000 cases had been confirmed by reverse transcription-polymerase chain reaction (RT-PCR). To study the lineages and the diversity of the viral population during this first epidemic wave in Madrid we sequenced 224 SARS-CoV-2 viral genomes collected from three hospitals from February to May 2020.

Eradication of Staphylococcus aureus Post-Sternotomy Mediastinitis Following the Implementation of Universal Preoperative Nasal Decontamination With Mupirocin: An Interrupted Time-Series Analysis.

Background: Although presurgical nasal decontamination with mupirocin (NDM) has been advocated as a measure for preventing postsurgical mediastinitis (PSM) due to Staphylococcus aureus, this strategy is not universally recommended due to lack of robust supporting evidence. We aimed to evaluate the role of preoperative NDM in the annual incidence of S. aureus PSM at our institution.

Genotypic and Phenotypic Characteristics of Prosthetic Joint Infections: Insight on the Pathogenesis and Prognosis of a Multicenter Prospective Cohort.

Background: is the leading cause of prosthetic joint infection (PJI). Beyond the antibiogram, little attention has been paid to the influence of deep microbiological characteristics on patient prognosis. Our aim was to investigate whether microbiological genotypic and phenotypic features have a significant influence on infection pathogenesis and patient outcome.

Pathogenic characteristics of Pseudomonas aeruginosa bacteraemia isolates in a high-endemicity setting for ST175 and ST235 high-risk clones.

Multidrug-resistant (MDR) Pseudomonas aeruginosa represents a major clinical concern. The interplay between antimicrobial resistance and virulence of P. aeruginosa was investigated in in vitro and in vivo studies.

Predictors of Mortality in Bloodstream Infections Caused by Pseudomonas aeruginosa and Impact of Antimicrobial Resistance and Bacterial Virulence.

Whether multidrug resistance (MDR) is associated with mortality in patients with bloodstream infections (BSI) remains controversial. Here, we explored the prognostic factors of BSI with emphasis on antimicrobial resistance and virulence. All BSI episodes in a 5-year period were retrospectively analyzed.

Intraosteoblastic activity of levofloxacin and rifampin alone and in combination against clinical isolates of meticillin-susceptible Staphylococcus aureus causing prosthetic joint infection.

Background: Staphylococcus aureus may invade and persist intracellularly in prosthetic joint infections (PJIs). Despite optimized treatments with levofloxacin plus rifampin, the intracellular reservoir may lead to infection relapse. This study assessed the intracellular activity of levofloxacin and rifampin in an in-vitro model of human osteoblastic infection.

Molecular Epidemiology of Bacteremia: Association of Molecular Factors With the Source of Infection.

bacteremia (SAB) is associated with high morbidity and mortality, which varies depending on the source of infection. Nevertheless, the global molecular epidemiology of SAB and its possible association with specific virulence factors remains unclear. Using DNA microarrays, a total of 833 strains (785 SAB and 48 colonizing strains) collected in Spain over a period of 15 years (2002-2017) were characterized to determine clonal complex (CC), type and repertoire of resistance and virulence genes in order to provide an epidemiological overview of CCs causing bloodstream infection, and to analyze possible associations between virulence genes and the most common sources of bacteremia.

Sub-inhibitory concentrations of oxacillin modify the expression of agr locus in Staphylococcus aureus clinical strains belonging to different clonal complexes.

Background: The ability of Staphylococcus aureus to invade tissues and cause an infectious disease is the result of a multi-factorial process supported by the huge number of virulence factors inherent to this microorganism tightly regulated by the accessory gene regulator (agr). During antimicrobial therapy bacteria may be exposed to sub-inhibitory concentrations (subMICs) of antibiotics that may trigger transcriptional changes that may have an impact on the pathogenesis of infection. The objective of this study was to investigate the effect of oxacillin sub-MICs on agr system expression as the key component in the regulation of virulence in methicillin-susceptible (MSSA) and -resistant S.

Bacteraemia due to extensively drug-resistant Pseudomonas aeruginosa sequence type 235 high-risk clone: Facing the perfect storm.

Predictors of mortality and the impact of multidrug resistance and virulence on patients with Pseudomonas aeruginosa (PA) bacteraemia were evaluated. Patients with PA bacteraemia in a 12-month period were retrospectively analysed. Carbapenemase production, molecular typing and identification of virulence factor ExoU were carried out.