Comparative Whole-Genome Phylogeny of Animal, Environmental, and Human Strains Confirms the Genogroup Organization and Diversity of the Stenotrophomonas maltophilia Complex.

The Stenotrophomonas maltophilia complex (Smc) comprises opportunistic environmental Gram-negative bacilli responsible for a variety of infections in both humans and animals. Beyond its large genetic diversity, its genetic organization in genogroups was recently confirmed through the whole-genome sequencing of human and environmental strains. As they are poorly represented in these analyses, we sequenced the whole genomes of 93 animal strains to determine their genetic background and characteristics. Combining these data with 81 newly sequenced human strains and the genomes available from RefSeq, we performed a genomic analysis that included 375 nonduplicated genomes with various origins (animal, 104; human, 226; environment, 30; unknown, 15). Phylogenetic analysis and clustering based on genome-wide average nucleotide identity confirmed and specified the genetic organization of Smc in at least 20 genogroups. Two new genogroups were identified, and two previously described groups were further divided into two subgroups each. Comparing the strains isolated from different host types and their genogroup affiliation, we observed a clear disequilibrium in certain groups. Surprisingly, some antimicrobial resistance genes, integrons, and/or clusters of attC sites lacking integron-integrase (CALIN) sequences targeting antimicrobial compounds extensively used in animals were mainly identified in animal strains. We also identified genes commonly found in animal strains coding for efflux systems. The result of a large whole-genome analysis performed by us supports the hypothesis of the putative contribution of animals as a reservoir of Stenotrophomonas maltophilia complex strains and/or resistance genes for strains in humans.IMPORTANCE Given its naturally large antimicrobial resistance profile, the Stenotrophomonas maltophilia complex (Smc) is a set of emerging pathogens of immunosuppressed and cystic fibrosis patients. As it is group of environmental microorganisms, this adaptation to humans is an opportunity to understand the genetic and metabolic selective mechanisms involved in this process. The previously reported genomic organization was incomplete, as data from animal strains were underrepresented. We added the missing piece of the puzzle with whole-genome sequencing of 93 strains of animal origin. Beyond describing the phylogenetic organization, we confirmed the genetic diversity of the Smc, which could not be estimated through routine phenotype- or matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF)-based laboratory tests. Animals strains seem to play a key role in the diversity of Smc and could act as a reservoir for mobile resistance genes. Some genogroups seem to be associated with particular hosts; the genetic support of this association and the role of the determinants/corresponding genes need to be explored.

Propionibacterium namnetense sp. nov., isolated from a human bone infection.

A polyphasic taxonomic study was performed on two Gram-positive-staining, anaerobic, pleomorphic, rod-shaped strains isolated from human bone and tissue samples. Sequencing of the 16S rRNA genes revealed that the strains belong to a novel species within the genus Propionibacterium, most closely related to Propionibacterium acnes subsp. acnes and Propionibacterium acnes subsp. elongatum with similarity values of 98.4 % and 98.1 %, respectively. In addition, protein-coding genes for rpoB, recA and gyrB clearly separated the novel organism from all species and subspecies of the genus Propionibacterium. However, a DNA-DNA hybridization analysis between the novel organism and the type strain P. acnes ATCC 6919T revealed a value of only 61.1 %. Furthermore, whole genome analysis using the program OrthoANI gave a value of 88.5 %, which is significantly below the cut-off value of 95 % for species delineation. The major fatty acids were iso-C15 : 0, anteiso-C15 : 0 and iso-C17 : 0. The DNA G+C content of the type strain was 59.7 mol%. When taken collectively, phenotypic, molecular genetic, chemotaxonomic and phylogenetic information demonstrate that the organism represents a distinct, albeit close relative of P. acnes On the basis of the results presented, the organism represents a novel member of the genus Propionibacterium for which the name Propionibacterium namnetense sp. nov. is proposed. The type strain is NTS 31307302T (=DSM 29427T=CCUG 66358T).

Proposed reclassification of Pasteurella lymphangitidis Sneath & Stevens 1990 as Yersinia pseudotuberculosis.

The 16S rRNA gene sequences of Pasteurella lymphangitidis, Yersinia pseudotuberculosis and Yersinia pestis were found to be identical and multilocus sequence analysis could not discriminate between the three species. The susceptibility to a Y. pseudotuberculosis phage and the presence of the Y. pseudotuberculosis-specific invasin gene in P. lymphangitidis indicate that the latter should be reclassified as Y. pseudotuberculosis.

Evaluation of the French surveillance system for epidemiological surveillance of antimicrobial resistance in the community and nursing homes.

Background: Antimicrobial resistance (AMR) has been widely recognized as a major public health issue, which can be addressed through effective AMR surveillance systems. In 2018, a national surveillance programme for AMR in the community and nursing homes called Mission PRIMO was established in France. It builds on an existing network called MedQual-Ville that had been monitoring AMR mainly in the west of France community since 2003. Objectives and Methods: To evaluate the MedQual-Ville surveillance activities and to formulate practical recommendations for improvement, using a semi-quantitative evaluation framework called OASIS. Results: The evaluation showed that MedQual-Ville is overall a well-performing surveillance system. Its major strengths rely on excellent coordination and internal communication with clinical laboratories that participate on a voluntary basis. Surveillance objectives and procedures are clear to all participants. Hence, the quality and reliability of the data being produced is very high. At this stage, the major area for improvement is representativeness, with poor coverage achieved in several densely populated areas. Besides, the utility and impact of surveillance data could be improved by strengthening communication towards end-users, especially local prescribers. Conclusions: There is currently no European programme or guidance for AMR surveillance in the community and nursing homes. Our results partly fill this gap, by evaluating how surveillance is being performed in France and providing recommendations that could be applicable to other countries with similar health systems. This work also highlighted the relevance of OASIS for evaluation of surveillance systems in the human sector.

Assessment of Factors Associated With Community-Acquired Extended-Spectrum ß-Lactamase-Producing Escherichia coli Urinary Tract Infections in France.

Importance: Extended-spectrum ß-lactamase (ESBL)-producing Escherichia coli is considered a leading pathogen contributing to the global burden of antimicrobial resistance. Objective: To better understand factors associated with the heterogeneity of community-acquired ESBL-producing E coli urinary tract infections (UTIs) in France. Design, Setting, and Participants: This cross-sectional study performed from January 1 to December 31, 2021, was based on data collected via PRIMO (Surveillance and Prevention of Antimicrobial Resistance in Primary Care and Nursing Homes), a nationwide clinical laboratory surveillance system in France. Strains of E coli isolated from community urine samples from January 1 to December 31, 2019, from 59 administrative departments of metropolitan France were included. Main Outcomes and Measures: Quasi-Poisson regression models were used to assess the associations between several ecological factors available on government and administration websites between 2010 and 2020 (demographic population structure, living conditions, baseline health care services, antibiotic consumptions, economic indicators, animal farming density, and environmental characteristics) and the number of ESBL-producing E coli strains isolated from urine samples of individuals with community-acquired UTI in 2019. Results: Among 444 281 E coli isolates from urine samples tested in 1013 laboratories, the mean prevalence of ESBL-producing E coli was 3.0% (range, 1.4%-8.8%). In an adjusted model, the number of community-acquired ESBL-producing E coli UTIs in each department was positively associated with the percentage of children younger than 5 years (adjusted ß1 coefficient, 0.112 [95% CI, 0.040-0.185]; P = .004), overcrowded households (adjusted ß1 coefficient, 0.049 [95% CI, 0.034 to 0.062]; P < .001), consumption of fluoroquinolones (adjusted ß1 coefficient, 0.002 [95% CI, 0.001-0.002]; P < .001), and tetracyclines (adjusted ß1 coefficient, 0.0002 [0.00004 to 0.00039]; P = .02), and poultry density (adjusted ß1 coefficient, 0.0001 [95% CI, 0.0001-0.0002]; P < .001). The social deprivation index (adjusted ß1 coefficient, -0.115 [95% CI, -0.165 to -0.064]; P < .001) and the proportion of water surface area (adjusted ß1 coefficient, -0.052 [-0.081 to -0.024]; P = .001) were negatively associated with a higher number of community-acquired ESBL-producing E coli UTIs. Conclusions and Relevance: The findings of this cross-sectional study suggest that multiple human health, animal health, and environmental factors are associated with the occurence of community-acquired ESBL E coli UTI. Strategies to mitigate ESBL in the community should follow the One Health approach and address the role played by fluoroquinolones, tetracycline use, poultry density, overcrowded households, and preschool-aged children.

Identification of Streptomyces spp. in a Clinical Sample: Always Contamination? Results of a French Retrospective Study.

Background: Streptomyces are environmental gram-positive bacilli that can cause ubiquitous mycetoma and, more rarely, invasive infections. We describe the clinical relevance of Streptomyces spp. identified in human samples and characteristics of patients with invasive Streptomyces infections. Methods: We conducted a retrospective (2006-2017) study of Streptomyces isolates identified in clinical samples in French microbiology laboratories. Streptomyces genus was confirmed by a specific 16S rRNA polymerase chain reaction, and antibiotic susceptibility testing was performed by disk diffusion and trimethoprim-sulfamethoxazole minimum inhibitory concentration (E-test) if resistance was suspected. Patient characteristics, treatments, and outcomes were collected. Invasive infection was defined as a positive culture from a sterile site with signs of infection but without cutaneous inoculation. Results: Of 137 Streptomyces isolates, all were susceptible to amikacin (113/113) and linezolid (112/112), and 92.9% to imipenem (105/113). Using disk diffusion, 50.9% (57/112) of isolates were susceptible to trimethoprim-sulfamethoxazole, but most of the apparently resistant isolates (25/36, 69.4%) tested by E-test were ultimately classified as susceptible. Clinical data were obtained for 63/137 (45.9%) isolates: 30 (47.6%) invasive infections, 8 (12.7%) primary cutaneous infections, 22 (34.9%) contaminations, 3 (4.7%) respiratory colonization. Patients with invasive infection were more frequently receiving corticosteroids than patients without invasive infection (11/30, 36.7%, vs 2/25, 8.0%; P = .03), and at 6-month follow-up, 14 of them were cured, 3 had relapsed, 4 were dead, and 9 were lost to follow-up. Conclusions: Half of the clinical samples that grew Streptomyces were from patients with invasive infection. In that case, antimicrobial therapy should include 1 or 2 antibiotics among linezolid, amikacin, or imipenem.

Decreasing proportion of extended-spectrum beta-lactamase among E. coli infections during the COVID-19 pandemic in France.

OBJECTIVES: We investigated the impact of the COVID-19 and national pandemic response on the epidemiology of Extended Spectrum Beta-Lactamase producing E. coli (ESBL-E.coli) in France. METHODS: Individual microbiology records from clinical laboratories were analyzed between 1 January 2019 to 31 December 2020. The ESBL-E.coli rates from clinical samples of patients in primary care and nursing home residents were compared before and after the general lockdown in March 2020, according to demographic and geographical characteristics. Interrupted time series analyses were performed to detect measurable changes in the trend of ESBL-E.coli rates. RESULTS: Records covering 793,954 E. coli isolates from 1022 clinical laboratories were analyzed. In primary care, 3.1% of E. coli isolates from clinical samples were producing ESBL before March 2020 and 2.9% since May 2020 (p < 0.001). The proportion of ESBL-E.coli decreased significantly among urine cultures, females, age categories 5-19, 40-64, > 65 year-old, and in the North, West, East and South-East regions. In nursing home, the ESBL-E.coli rate was 9.3% (monthly rate min-max: 6.5-10.5%) before March 2020 and 8.3% (7.2-9.1%) since May 2020 (p < 0.001). The reduction rate accelerated from -0.04%/month to -0.22%/month from May 2020 (p < 0.001). CONCLUSION: Investigation of factors that led to the decreased proportion of ESBL-E.coli during the COVID-19 pandemic is urgently needed.

[Comparison of antimicrobial susceptibility of 1,217 Escherichia coli isolates from women with hospital and community-acquired urinary tract infections]. / Comparaison de la sensibilité aux antibiotiques de 1,217 isolats consécutifs de Escherichia coli responsables d'infections urinaires féminines en ville et à l'hôpital.

INTRODUCTION: The treatment of urinary tract infection (UTI) in women is based mainly on empirical antibiotic therapy. It requires up-to-date knowledge of the susceptibility patterns of the bacteria most commonly identified in that setting. The aim of this prospective study was to measure the antibiotic susceptibility of Escherichia coli isolates responsible for UTIs in women from a single area and to compare it in hospital and community settings. MATERIALS AND METHODS: From May 2003 through April 2004, UTI was diagnosed in 1838 women around Rennes (France), 893 of them inpatients admitted to the teaching hospital and 945 outpatients in the community. We determined the susceptibility to 7 antibiotics of the resulting 1217 E. coli isolates. RESULTS: E. coli resistance rates in hospitalized and community patients were respectively 47.9% and 39.2% for aminopenicillins, 47.3% and 25.4% for coamoxiclav, 19.2% and 14.1% for cotrimoxazole, 14.3% and 5.7% for first-generation quinolones, and 8.9% and 3.7% for fluoroquinolones. All these rates were significantly higher among hospitalized patients (p<0.05). Conversely, resistance to injectable third-generation cephalosporins and fosfomycin was similar and infrequent in both groups. CONCLUSION: Comparisons with previous data show that activity of third-generation cephalosporins and fosfomycin on E. coli appears unchanged, in contrast to the increased resistance rates to other antibiotics usually prescribed for UTI.

The sodA gene as a target for phylogenetic dissection of the genus Haemophilus and accurate identification of human clinical isolates.

The genus Haemophilus constitutes a heterogeneous group of Pasteurellaceae species, and conventional identification of isolates other than Haemophilus influenzae and Haemophilus parainfluenzae is often challenging. Here, simple colony-PCR and sequencing assays with the same pair of degenerate primers were used to characterize a 449- to 458-bp fragment (sodA(int)) internal to the sodA gene encoding the manganese-dependent superoxide dismutase in type strains of all 15 Haemophilus species and Actinobacillus actinomycetemcomitans. The topology of a sodA(int)-based phylogenetic tree was in general agreement with that inferred from the analysis of 16S rRNA and other housekeeping gene sequences, but allowed more confident delineation of the main clusters of species. The sodA(int) sequences showed a markedly higher divergence than those of the corresponding 16S rRNA genes, and 38 independent human clinical isolates were identified by comparing their sodA(int) sequence to those of the type species. Except for one Haemophilus aphrophilus strain, all isolates were unambiguously characterized in spite of a high intraspecific sodA(int) sequence diversity. This study provides a comprehensive sequence-based phylogenetic analysis of the entire genus Haemophilus, and confirms that sodA is a potent target for the identification of clinical isolates of Pasteurellaceae. This approach might contribute to the taxonomic reappraisal of this family, and to the development of diagnostic tools.

In vitro and ex vivo permissivity of hepatocytes for Leishmania donovani.

Using models of ex vivo infection of murine, rat, and human primary hepatocytes by Leishmania donovani, we showed that hepatocytes are permissive for Leishmania at a low level. We then modeled the in vitro infection of a human hepatoma-derived cell line to examine the parasite's capability to proliferate and to cause direct damage to hepatocytes. Results showed that L. donovani can infect hepatocytes, but do not massively proliferate. This slight infection under our experimental conditions resulted in limited damage to hepatocytes. These results bring into question a possible role for hepatocytes as a parasite reservoir during latent infection.