Azithromycin regulates bacterial virulence and immune response in a murine model of ceftazidime-treated Pseudomonas aeruginosa acute pneumonia.

Pseudomonas aeruginosa (PA) remains one of the leading causes of nosocomial acute pneumonia. The array of virulence factors expressed by PA and the intense immune response associated with PA pneumonia play a major role in the severity of these infections. New therapeutic approaches are needed to overcome the high resistance of PA to antibiotics and to reduce the direct damage to host tissues.

susceptibility of nonfermenting Gram-negative rods to meropenem-vaborbactam and delafloxacin.

Meropenem-vaborbactam and delafloxacin activities were not assessed against spp. (), complex () and (). A total of 106 , 57  and 100  were tested with gradient diffusion test of meropenem-vaborbactam, delafloxacin and comparators.

Comparison of Aztreonam/Amoxicillin-Clavulanate Versus Aztreonam/Ceftazidime-Avibactam on Ceftazidime-Avibactam Resistant .

We investigated the susceptibility of ceftazidime-avibactam (CZA) resistant to the associations aztreonam/amoxicillin-clavulanate (ATM-AMC) and ATM-CZA. Forty clinical isolates of recovered from sputum samples of 40 cystic fibrosis people were selected from the collection of the Nantes University Hospital, based on their resistance to CZA. Minimum inhibitory concentrations (MICs) of ATM-CZA and ATM-AMC were determined for each isolate by an Etest strip superposition method, and by Etest for each individual antibiotic.

Matrix-Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry for Rapid Detection of Isolates Belonging to the Epidemic Clones Achromobacter xylosoxidans ST137 and Achromobacter ruhlandii DES from Cystic Fibrosis Patients.

spp. are increasingly reported among cystic fibrosis patients. Genotyping requires time-consuming methods such as multilocus sequence typing or pulsed-field gel electrophoresis.

Antibiotic resistance heterogeneity and LasR diversity within Pseudomonas aeruginosa populations from pneumonia in intensive care unit patients.

This study investigated within-host heterogeneity of 66 Pseudomonas aeruginosa populations from pneumonia in 51 critically ill ventilated patients by examining 30 colonies per bronchoalveolar lavage (BAL). Differences in antibiotic susceptibility and quorum-sensing (QS) phenotypes were observed between the members of 14 (21.2%) and 10 (15.

Could Azithromycin Be Part of Acute Pneumonia Treatment?

Azithromycin (AZM) is a 15-membered-ring macrolide that presents a broad-spectrum antimicrobial activity against Gram-positive bacteria and atypical microorganisms but suffers from a poor diffusion across the outer-membrane of Gram-negative bacilli, including (PA). However, AZM has demonstrated clinical benefits in patients suffering from chronic PA respiratory infections, especially cystic fibrosis patients. Since the rise of multidrug-resistant PA has led to a growing need for new therapeutic options, this macrolide has been proposed as an adjunctive therapy.

Rapid genetic and phenotypic changes in Pseudomonas aeruginosa clinical strains during ventilator-associated pneumonia.

Treatment with antibiotics leads to the selection of isolates with increased resistance. We investigated if evolution towards resistance was associated with virulence changes, in the context of P. aeruginosa ventilator-associated pneumonia (VAP).

New parameters on the hematology analyzer XN-10 (SysmexTM) allow to distinguish childhood bacterial and viral infections.

Introduction: Complete blood counts (CBC) performed for infected children admitted for fever mostly disclose leukocytosis. Yet, the recently developed XN-10 provides novel CBC parameters which could be useful to ascertain infection and discriminate between bacterial and viral etiologies. These were the main objectives of the study presented here.

Innate immune evasion of Escherichia coli clinical strains from orthopedic implant infections.

Escherichia coli is one of the first causes of Gram-negative orthopedic implant infections (OII). Those infections, usually hematogenous, mostly originate from the urinary tract. We investigated the strategies developed by E.

Inhibition profiles of mono- and polyvalent FimH antagonists against 10 different Escherichia coli strains.

Mono- and polyvalent ligands with strong affinities for the mannose-binding adhesin FimH were synthesised, and their anti-adhesive properties against ten E. coli strains were compared in two cell-based assays. The compounds were assessed against the non-pathogenic E.

Pathogenic potential of Escherichia coli clinical strains from orthopedic implant infections towards human osteoblastic cells.

Escherichia coli is one of the first causes of Gram-negative orthopedic implant infections (OII), but little is known about the pathogenicity of this species in such infections that are increasing due to the ageing of the population. We report how this pathogen interacts with human osteoblastic MG-63 cells in vitro, by comparing 20 OII E. coli strains to two Staphylococcus aureus and two Pseudomonas aeruginosa strains.

Subversion of human intestinal mucosa innate immunity by a Crohn's disease-associated E. coli.

Adherent-invasive Escherichia coli (AIEC), associated with Crohn's disease, are likely candidate contributory factors in the disease. However, signaling pathways involved in human intestinal mucosa innate host response to AIEC remain unknown. Here we use a 3D model of human intestinal mucosa explant culture to explore the effects of the AIEC strain LF82 on two innate immunity platforms, i.

TEM-187, a new extended-spectrum β-lactamase with weak activity in a Proteus mirabilis clinical strain.

A Proteus mirabilis clinical strain (7001324) was isolated from urine sample of a patient hospitalized in a long-term-care facility. PCR and cloning experiments performed with this strain identified a novel TEM-type β-lactamase (TEM-187) differing by four amino acid substitutions (Leu21Phe, Arg164His, Ala184Val, and Thr265Met) from TEM-1. This characterization provides further evidence for the diversity of extended-spectrum β-lactamases (ESBL) produced by P.

Comparison of three methods to study biofilm formation by clinical strains of Escherichia coli.

Biofilm formation seems to be a key factor in many bacterial infections, particularly those involving prosthetic implants or urinary catheters, where Escherichia coli is frequently involved. We have determined the ability to form biofilm in vitro of 34 E. coli isolates by 3 different methods (crystal violet staining, BioFilm Ring Test®, and resazurin assay) and tried to correlate biofilm production with phylogenetic background and with the presence of different genes involved in biofilm synthesis.

Detection of clonally related Escherichia coli isolates producing different CMY β-lactamases from a cystic fibrosis patient.

Objectives: This study reports details on Escherichia coli isolates recovered from a cystic fibrosis (CF) patient in order to understand how this pathogen adapts to and resists broad-spectrum antipseudomonal therapy in this context.

Methods: Five E. coli isolates were obtained from various clinical samples (airways, urine or dialysis catheter) over a 7 month period covering a double-lung transplantation.

Investigation and management of multidrug-resistant Acinetobacter baumannii spread in a French medical intensive care unit: one outbreak may hide another.

An outbreak in a medical intensive care unit was due to an OXA-23-producing Acinetobacter baumannii strain imported from a repatriate hospitalized in Singapore. This outbreak revealed another multidrug resistant epidemic strain that had been present in the hospital for 2 years. Both outbreaks were controlled after 9 months of an extensive infection control program.

[Impact of enterobacteriaceae-producing extended-spectrum beta-lactamases (ESBLE) incidence increasing on barrier precautions implementation in a university hospital].

Aim Of The Study: The French national surveillance program of multidrug-resistant bacteria (MDR) shows an increase of enterobacteriaceae-producing extended-spectrum beta-lactamases (ESBLE) incidence. The objectives of this study were to assess: the incidence of EBLSE in a large French university hospital between 2005 and 2010, and the difference of barrier precautions implementation between ESBL and other MDR.

Methods: The ESBLE incidence measure used data from the laboratory of bacteriology.

Genotypic and phenotypic characterization of Staphylococcus epidermidis causing chronic relapsing prosthetic joint infections.

Twenty-one isolates of Staphylococcus epidermidis from 9 patients with persistent prosthetic joint infections were analysed by pulsed-field gel electrophoresis and antibiotic susceptibility assays. In 7 of these cases, the S. epidermidis isolate was different from that of the initial episode.