Amoeba plate test with as an innovative tool for recovery from sputum samples: a proof-of-concept study.

Unlabelled: recovery from pulmonary samples is challenging due to the lack of a specific medium and the abundance of overgrown respiratory flora. This study aimed to compare the amoeba plate test (APT), an amoebic coculture with , with the axenic culture to recover from pulmonary samples. serial dilutions ( = 15 strains from seven species, concentrations ranging: 10-10 CFU/mL) in water and spiked overgrown sputa ( = 8) were simultaneously plated on agar with amoebic monolayer (APT) and without (control).

Detection of highly macrolide-resistant Legionella pneumophila strains from a hotel water network using systematic whole-genome sequencing.

Objectives: Implementation of an antibiotic resistance detection tool in Legionella daily surveillance at the French National Reference Centre for Legionella.

Methods: Systematic WGS of Legionella pneumophila isolates and bioinformatics detection of specific mutations linked to antibiotic resistance. Phenotypic validation of antibiotic resistance detected by WGS was performed by the broth microdilution method.

Sub-Inhibitory Concentrations of Oxacillin, but Not Clindamycin, Linezolid, or Tigecycline, Decrease Staphylococcal Phenol-Soluble Modulin Expression in Community-Acquired Methicillin-Resistant Staphylococcus aureus.

Staphylococcus aureus (SA) is a major human pathogen producing virulence factors, such as Panton-Valentine-leucocidin (PVL), alpha-hemolysin (Hla), and phenol-soluble-modulins alpha (PSMα), including delta-hemolysin (Hld). Unlike oxacillin, clindamycin and linezolid subinhibitory concentrations (sub-MIC) display an anti-toxin effect on PVL and Hla expression. Few studies have investigated PSMα and Hld expression modulation by antibiotics.

Co-infection with Legionella and SARS-CoV-2, France, March 2020.

We describe a March 2020 co-occurrence of Legionnaires' disease (LD) and coronavirus disease in France. Severe acute respiratory syndrome coronavirus 2 co-infections were identified in 7 of 49 patients from LD case notifications. Most were elderly men with underlying conditions who had contracted severe pneumonia, illustrating the relevance of co-infection screening.

Transmission of Legionnaires' Disease through Toilet Flushing.

We describe 2 cases of healthcare-associated Legionnaires' disease in patients in France hospitalized 5 months apart in the same room. Whole-genome sequencing analyses showed that clinical isolates from the patients and isolates from the room's toilet clustered together. Toilet contamination by Legionella pneumophila could lead to a risk for exposure through flushing.

Comparison of Legionella K-set® and BinaxNOW® Legionella for diagnosing Legionnaires' disease on concentrated urine samples.

Detection of Legionella pneumophila serogroup 1 urinary antigens is the most widely used technique for the diagnosis of Legionnaires' disease (LD). The aim of this study was to evaluate the performance of the Legionella K-set® immunochromatographic test, in comparison with the BinaxNOW® Legionella urinary antigen card (UAC) on concentrated urine samples (US). A total of 250 concentrated US including 200 prospective US sent to the laboratory for urinary antigens' testing and 50 frozen US from patients with confirmed LD were tested.

The clinical presentation of Legionella arthritis reveals the mode of infection and the bacterial species: case report and literature review.

Background: While Legionella is a common cause of pneumonia, extrapulmonary infections like arthritis are scarce. Here, we describe a case of monoarthritis due to Legionella bozemanii, with no history of pneumonia. We provide a literature review of the 9 previously published Legionella arthritis and highlight a dichotomous epidemiology suggesting different physiopathological pathways leading to joint infection.

Diversity and trends in population structure of ESBL-producing Enterobacteriaceae in febrile urinary tract infections in children in France from 2014 to 2017.

Background: The population structure of extraintestinal pathogenic Escherichia coli evolves over time, notably due to the emergence of antibiotic-resistant clones such as ESBL-producing Enterobacteriaceae (ESBL-E).

Objectives: To analyse by WGS the genetic diversity of a large number of ESBL-E isolated from urinary tract infections in children from paediatric centres across France between 2014 and 2017 and collected by the National Observatory of febrile urinary tract infection (FUTI) caused by ESBL-E.

Methods: A total of 40 905 Enterobacteriaceae-positive urine cultures were identified.

Slowly or Nonresolving Legionnaires' Disease: Case Series and Literature Review.

Background: Rarely, Legionnaires' disease (LD) can progress into a slowly or nonresolving form.

Methods: A nationwide retrospective study was conducted by the French National Reference Center for Legionella (2013-2017) including cases of slowly or nonresolving LD defined as persistent clinical symptoms, computed tomography (CT) scan abnormalities, and Legionella detection in lower respiratory tract specimens by culture and/or real-time (RT) polymerase chain reaction (PCR) >30 days after symptom onset.

Results: Twelve cases of community-acquired slowly or nonresolving LD were identified among 1686 cases of culture-positive LD.

[Validation of the usual values provided by a supplier without access to a control population: example of serum amyloid A].

Unlabelled: As part of the laboratory accreditation process, it may be required to determine the laboratory's own reference values. Thus, we have accredited in our laboratory, the serum amyloid A (SAA) assay for which the supplier gave the usual values. However, we did not have a reference population to check them.

Legionella pneumophila LPS to evaluate urinary antigen tests.

Three urinary antigen tests were compared using purified Legionella pneumophila (Lp) LPS. For Lp serogroup1, Sofia®FIA and Binax®EIA limits of detection (LOD) were similar; that of BinaxNOW® lower. For all tests the LOD was higher with LPS from non-Pontiac compared to Pontiac-strains.

Digital PCR for Detection and Quantification of Fluoroquinolone Resistance in Legionella pneumophila.

The emergence of fluoroquinolone (FQ)-resistant mutants of in infected humans was previously reported using a next-generation DNA sequencing (NGS) approach. This finding could explain part of the therapeutic failures observed in legionellosis patients treated with these antibiotics. The aim of this study was to develop digital PCR (dPCR) assays allowing rapid and accurate detection and quantification of these resistant mutants in respiratory samples, especially when the proportion of mutants in a wild-type background is low.

Phenol-soluble modulin α induces G2/M phase transition delay in eukaryotic HeLa cells.

Staphylococcus aureus is a gram-positive bacterium responsible for a wide range of infections. Host cell cycle alteration is a sophisticated mechanism used by pathogens to hijack the defense functions of host cells. We previously demonstrated that S.