Deciphering the role of the conjugate's phycoerythrin label in complement-mediated interference occurring in HLA single antigen Luminex bead assays.

Complement-mediated interference is a well described phenomenon in single antigen bead (SAB) Luminex assay that leads to falsely low or negative results for anti-HLA antibody (Ab). In a context of high amount of Ab, the enrichment of the Ab around the bead can lead to complement cascade activation and deposition, thereafter impairing Ab detection. EDTA is now routinely used to circumvent this interference.

Type II Fatty Acid Synthesis Pathway and Cyclopropane Ring Formation Are Dispensable during Enterococcus faecalis Systemic Infection.

Enterococcus faecalis, a multiple antibiotic-resistant Gram-positive bacterium, has emerged as a serious nosocomial pathogen. Here, we used a genetic approach to characterize the strategies used by E. faecalis to fulfill its requirements for endogenous fatty acid (FA) synthesis and .

Multidrug-Resistant Hypervirulent Group B Streptococcus in Neonatal Invasive Infections, France, 2007-2019.

We analyzed group B Streptococcus (GBS) neonatal invasive infections reported during 2007-2019 in France. The hypervirulent clonal complex (CC) 17 GBS was responsible for 66% (827/1,262) of cases. The role of CC17 GBS increased over time (p for trend = 0.

Invasive group B Streptococcus infections in non-pregnant adults: a retrospective study, France, 2007-2019.

Objectives: Group B Streptococcus (GBS) (Streptococcus agalactiae) is a pathogen of growing importance in adults. The objective of this study was to describe the features of invasive infections by GBS in non-pregnant adults.

Methods: GBS infections were reported to the national reference centre for streptococci.

Perinatal hormones favor CC17 group B intestinal translocation through M cells and hypervirulence in neonates.

Group B (GBS) is the leading cause of invasive bacterial neonatal infections. Late-onset diseases (LOD) occur between 7 and 89 days of life and are largely due to the CC17 GBS hypervirulent clone. We studied the impact of estradiol (E2) and progesterone (P4), which impregnate the fetus during pregnancy, on GBS neonatal infection in cellular and mouse models of hormonal exposure corresponding to concentrations found at birth (E2-P4 C) and over 7 days old (E2-P4 C).

Molecular diagnosis of Helicobacter pylori infection in gastric biopsies: Evaluation of the Amplidiag H. pylori + ClariR assay.

Background: Adapted treatments for Helicobacter pylori infection, guided by determining antimicrobial resistance, are associated with high eradication rates. We evaluated the performance of the Amplidiag H. pylori + ClariR PCR assay (Amplidiag ) for detecting H.

Molecular characterization of Helicobacter pylori resistance to rifamycins.

Introduction: Antibiotic resistance is a major contributing factor in treatment failure of Helicobacter pylori eradication. Rifabutin (RB) is a rescue treatment and rifampicin (RP) is used to screen RB resistance in vitro. The aim of this study was to evaluate the rate of rifamycins resistance and to determine the mutations in the rpoB gene conferring resistance to discuss the current break point.

Changing Epidemiology of Group B Streptococcus Susceptibility to Fluoroquinolones and Aminoglycosides in France.

Group B Streptococcus (GBS) is the leading cause of neonatal invasive infections and an emerging pathogen in the elderly. Our objectives were to describe the evolution of GBS resistance to antibiotics in France and to investigate the emergence of fluoroquinolone (FQ)-resistant isolates. A total of 8,757 unrelated GBS isolates were collected and tested for antibiotic susceptibility from 2007 to 2014 according to EUCAST recommendations.

Environmental fatty acids enable emergence of infectious Staphylococcus aureus resistant to FASII-targeted antimicrobials.

The bacterial pathway for fatty acid biosynthesis, FASII, is a target for development of new anti-staphylococcal drugs. This strategy is based on previous reports indicating that self-synthesized fatty acids appear to be indispensable for Staphylococcus aureus growth and virulence, although other bacteria can use exogenous fatty acids to compensate FASII inhibition. Here we report that staphylococci can become resistant to the FASII-targeted inhibitor triclosan via high frequency mutations in fabD, one of the FASII genes.

Molecular characterization of Streptococcus agalactiae isolates harboring small erm(T)-carrying plasmids.

Among 1,827 group B Streptococcus (GBS) strains collected between 2006 and 2013 by the French National Reference Center for Streptococci, 490 (26.8%) strains were erythromycin resistant. The erm(T) resistance gene was found in six strains belonging to capsular polysaccharides Ia, III, and V and was carried by the same mobilizable plasmid, which could be efficiently transferred by mobilization to GBS and Enterococcus faecalis recipients, thus promoting a broad dissemination of erm(T).

Erm(X)-mediated resistance to macrolides, lincosamides and streptogramins in Actinobaculum schaalii.

Objectives: Actinobaculum schaalii is a Gram-positive bacillus increasingly reported as a causative agent of urinary tract infections as well as invasive infections, mainly in the elderly and patients with underlying urological conditions. Since little is known about the molecular basis of antimicrobial resistance in A. schaalii, the aim of this study was to investigate resistance to macrolides, lincosamides and streptogramins (MLS) in this emerging pathogen.

Emergence of NDM-1-producing Klebsiella pneumoniae in Morocco.

Objectives: To analyse the mechanisms responsible for multidrug resistance in three carbapenem-resistant Klebsiella pneumoniae isolates recovered from two hospitalized patients and an outpatient from the same hospital in Rabat, Morocco.

Methods: PCR and sequencing were used to search for β-lactamase genes. Clonal relationships between the isolates were analysed by multilocus sequence typing and PFGE.

Rapid and accurate identification of species belonging to the Candida parapsilosis complex by real-time PCR and melting curve analysis.

Candida parapsilosis is the second most frequent Candida species isolated from blood cultures. Since 2005, C. parapsilosis has been divided into three distinct species based on genetic traits: Candida parapsilosis, Candida metapsilosis and Candida orthopsilosis.