Characterization of Metallo β-Lactamase Producing Isolates with Susceptibility to the Aztreonam/Avibactam Combination.

Metallo-β-lactamases (MBLs) in and other Gram-negative organisms pose significant public health threats due to their association with multidrug resistance (MDR). Although aztreonam (AZT) can target MBL-producing organisms, its efficacy is compromised in organisms expressing additional β-lactamases that inactivate it. Combining AZT with the β-lactamase inhibitor avibactam (AVI) may restore its activity against MBL-producing isolates.

Early assessment of blood culture negativity as a potential support tool for antimicrobial stewardship.

Objective: To assess whether 48-h negative blood culture (BC) bottles are still negative at the classic 120-h incubation endpoint and whether 48 h might be the time to make antimicrobial therapy decisions.

Methods: Data from the first collected bottles from bloodstream infection (BSI) episodes of single patients were retrospectively analyzed. Probabilities of bottles being negative at the classic endpoint were calculated from 0 to 120 h of incubation.

In-depth characterization of multidrug-resistant NDM-1 and KPC-3 co-producing bloodstream isolates from Italian hospital patients.

Bloodstream infection (BSI) caused by carbapenem-resistant (KP) poses significant challenges, particularly when the infecting isolate carries multiple antimicrobial resistance (AMR) genes/determinants. This study, employing short- and long-read whole-genome sequencing, characterizes six New Delhi metallo-β-lactamase (NDM) 1 and KP carbapenemase (KPC) 3 co-producing KP isolates, the largest cohort investigated in Europe to date. Five [sequence type (ST) 512] and one (ST11) isolates were recovered from patients who developed BSI from February to August 2022 or February 2023 at two different hospitals in Rome, Italy.

Evaluation of Autof MS2600 and MBT Smart MALDI-TOF MS Systems for Routine Identification of Clinical Bacteria and Yeasts.

The identification of microorganisms at the species level has always constituted a diagnostic challenge for clinical microbiology laboratories. The aim of the present study has been the evaluation in a real-time assay of the performance of Autobio in comparison with the Bruker mass spectrometry system for the identification of bacteria and yeasts. A total of 535 bacteria and yeast were tested in parallel with the two systems by direct smear or fast formic acid extraction for bacteria and yeasts, respectively.

Effect of acute histologic chorioamnionitis on bronchopulmonary dysplasia and mortality rate among extremely low gestational age neonates: A retrospective case-control study.

Objective: To evaluate whether acute histologic chorioamnionitis (HCA) diagnosed in the placenta may be associated with an increased occurrence of bronchopulmonary dysplasia (BPD) or death among extremely low gestational age neonates (ELGAN).

Methods: This Italian single-center case-control retrospective study involved ELGAN admitted to the neonatal intensive care unit between January 2019 and June 2022. Infants born from pregnant women with acute and severe HCA, identified as stage ≥2 and grade 2 HCA, (HCA-infants) were compared with infants of pregnant women without chorioamnionitis or with stage 1, grade 1 chorioamnionitis (no-HCA-infants).