A New SPQC Biosensor for the Detection of a New Target of Escherichia/Shigella Genera Based on a Novel Method of Synthesizing Long-Range DNA.

The rapid and sensitive detection of Escherichia/Shigella genera is crucial for human disease and health. This study introduces a novel series of piezoelectric quartz crystal (SPQC) sensors for detecting Escherichia/Shigella genera. In this innovative biosensor, we propose a new target and novel method for synthesizing long-range DNA. The method relies on the amplification of two DNA probes, referred to as H and P amplification (HPA), resulting in the products of long-range DNA named Sn. The new target was screened from the 16S rRNA gene and utilized as a biomarker. The SPQC sensor operates as follows: the Capture probe is modified on the electrodes. In the presence of a Displace probe and target, the Capture can form a complex with the Displace probe. The resulting complex hybridizes with Sn, bridging the gap between the electrodes. Finally, silver wires are deposited between the electrodes using Sn as a template. This process results in a sensitive response from the SPQC. The detection limit of the SPQC sensor is 1 CFU/mL, and the detection time is within 2 h. This sensor would be of great benefit for food safety monitoring and clinical diagnosis.

Cloning and characterization of a hyaluronate lyase EsHyl8 from Escherichia sp. A99.

Hyaluronidase, an enzyme that degrades hyaluronic acid (HA), is utilized in clinical settings to facilitate drug diffusion, manage extravasation, and address injection-related complications linked to HA-based fillers. In this study, a novel hyaluronate lyase EsHyl8 was cloned, expressed, and characterized from Escherichia sp. A99 of human intestinal origin. This lyase belongs to polysaccharide lyase (PL) family 8, and showed specific activity towards HA. EsHyl8 exhibited optimal degradation at 40 °C and pH 6.0. EsHyl8 exhibited a high activity of 376.32 U/mg among hyaluronidases of human gut microorganisms. EsHyl8 was stable at 37 °C and remained about 70 % of activity after incubation at 37 °C for 24 h, demonstrating excellent thermostability. The activity of EsHyl8 was inhibited by Zn2+, Cu2+, Fe3+, and SDS. EsHyl8 was an endo-type enzyme whose end-product was unsaturated disaccharide. This study enhances our understanding of hyaluronidases from human gut microorganisms.

An outbreak associated with Escherichia albertii in a junior high school, China.

Escherichia albertii is an emerging foodborne enteropathogen associated with infectious diarrhoea in humans. In February 2023, an outbreak of acute gastroenteric cases was reported in a junior high school located in Hangzhou, Zhejiang province, China. Twenty-two investigated patients presented diarrhoea (22/22, 100%), abdominal pain (21/22, 95.5%), nausea (6/22, 27.3%), and vomiting (3/22, 13.6%). E. albertii strains were successfully isolated from anal swabs collected from six patients. Each isolate was classified as sequence type ST2686, harboured eae-ß gene, and carried both cdtB-I and cdtB-II subtypes, being serotyped as EAOg32:EAHg4 serotype. A comprehensive whole-genome phylogenetic analysis revealed that the six isolates formed a distinct cluster, separate from other strains. These isolates exhibited minimal genetic variation, differing from one another by 0 to 1 single nucleotide polymorphism, suggesting a common origin from a single clone. To the best of our knowledge, this represented the first reported outbreak of gastroenteritis attributed to E. albertii outside of Japan on a global scale.

The EnteroBase user's guide, with case studies on Salmonella transmissions, Yersinia pestis phylogeny, and Escherichia core genomic diversity.

EnteroBase is an integrated software environment that supports the identification of global population structures within several bacterial genera that include pathogens. Here, we provide an overview of how EnteroBase works, what it can do, and its future prospects. EnteroBase has currently assembled more than 300,000 genomes from Illumina short reads from Salmonella, Escherichia, Yersinia, Clostridioides, Helicobacter, Vibrio, and Moraxella and genotyped those assemblies by core genome multilocus sequence typing (cgMLST). Hierarchical clustering of cgMLST sequence types allows mapping a new bacterial strain to predefined population structures at multiple levels of resolution within a few hours after uploading its short reads. Case Study 1 illustrates this process for local transmissions of Salmonella enterica serovar Agama between neighboring social groups of badgers and humans. EnteroBase also supports single nucleotide polymorphism (SNP) calls from both genomic assemblies and after extraction from metagenomic sequences, as illustrated by Case Study 2 which summarizes the microevolution of Yersinia pestis over the last 5000 years of pandemic plague. EnteroBase can also provide a global overview of the genomic diversity within an entire genus, as illustrated by Case Study 3, which presents a novel, global overview of the population structure of all of the species, subspecies, and clades within Escherichia.

Biological characteristics and genomic analysis of a novel Escherichia phage Kayfunavirus CY1.

As the problem of bacterial resistance becomes serious day by day, bacteriophage as a potential antibiotic substitute attracts more and more researchers' interest. In this study, Escherichia phage Kayfunavirus CY1 was isolated from sewage samples of swine farms and identified by biological characteristics and genomic analysis. One-step growth curve showed that the latent period of phage CY1 was about 10 min, the outbreak period was about 40 min and the burst size was 35 PFU/cell. Analysis of the electron microscopy and whole-genome sequence showed that the phage should be classified as a member of the Autographiviridae family, Studiervirinae subfamily. Genomic analysis of phage CY1 (GenBank accession no. OM937123) revealed a genome size of 39,173 bp with an average GC content of 50.51% and 46 coding domain sequences (CDSs). Eight CDSs encoding proteins involved in the replication and regulation of phage DNA, 2 CDSs encoded lysis proteins, 14 CDSs encoded packing and morphogenesis proteins. Genomic and proteomic analysis identified no sequence that encoded for virulence factor, integration-related proteins or antibiotic resistance genes. In summary, morphological and genomics suggest that phage CY1 is more likely a novel Escherichia phage.

The phage defence island of a multidrug resistant plasmid uses both BREX and type IV restriction for complementary protection from viruses.

Bacteria have evolved a multitude of systems to prevent invasion by bacteriophages and other mobile genetic elements. Comparative genomics suggests that genes encoding bacterial defence mechanisms are often clustered in 'defence islands', providing a concerted level of protection against a wider range of attackers. However, there is a comparative paucity of information on functional interplay between multiple defence systems. Here, we have functionally characterised a defence island from a multidrug resistant plasmid of the emerging pathogen Escherichia fergusonii. Using a suite of thirty environmentally-isolated coliphages, we demonstrate multi-layered and robust phage protection provided by a plasmid-encoded defence island that expresses both a type I BREX system and the novel GmrSD-family type IV DNA modification-dependent restriction enzyme, BrxU. We present the structure of BrxU to 2.12 Å, the first structure of the GmrSD family of enzymes, and show that BrxU can utilise all common nucleotides and a wide selection of metals to cleave a range of modified DNAs. Additionally, BrxU undergoes a multi-step reaction cycle instigated by an unexpected ATP-dependent shift from an intertwined dimer to monomers. This direct evidence that bacterial defence islands can mediate complementary layers of phage protection enhances our understanding of the ever-expanding nature of phage-bacterial interactions.

Development of a Novel Real-Time Polymerase Chain Reaction Assay to Detect Escherichia albertii in Chicken Meat.

Escherichia albertii is an emerging enteropathogen. Several foodborne outbreaks of E. albertii have been reported in Japan; however, foods associated with most outbreaks remain unidentified. Therefore, polymerase chain reaction (PCR) assays detecting E. albertii specifically and sensitively are required. Primers and probe for real-time PCR assays targeting E. albertii-specific gene (EA-rtPCR) was designed. With 74 strains, including 43 E. albertii strains and several of its close relatives, EA-rtPCR specifically amplified E. albertii; therefore, the sensitivity of EA-rtPCR was then evaluated. The detection limits were 2.8 and 2.0-3.2 log colony-forming unit (CFU)/mL for E. albertii culture and enriched chicken culture inoculated with the pathogen, respectively. In addition, E. albertii was detected from 25 g of chicken meat inoculated with 0.1 log CFU of the pathogen by EA-rtPCR. The detection of E. albertii from chicken meat by EA-rtPCR was also evaluated by comparing with the nested-PCR assay, and 28 retail chicken meat and 193 dissected body parts from 21 chicken carcass were tested. One and three chicken meat were positive in the nested-PCR assay and EA-rtPCR, respectively. Fourteen carcasses had at least one body part that was positive for EA-rtPCR, and 36 and 48 samples were positive for the nested-PCR assay and EA-rtPCR, respectively. A total of 37 strains of E. albertii were isolated from seven PCR-positive samples obtained from six chicken carcass. All E. albertii isolates harbored eae gene, and were classified as E. albertii O-genotype (EAOg)3 or EAOg4 by EAO-genotyping. The EA-rtPCR developed in this study has potential to improve E. albertii detection in food and advance research on E. albertii infection.

A small RNA is functional in Escherichia fergusonii despite containing a large insertion.

Bacterial small RNAs (sRNAs) are important regulators of gene expression; however, the impact of natural mutations on sRNA functions has not been studied extensively. Here we show that the sRNA MgrR contains a unique 53 bp insertion in Escherichia fergusonii, a close relative of Escherichia coli and Salmonella enterica. The insertion is a repetitive extragenic palindromic (REP) sequence that could block transcription, but full-length MgrR is produced in E. fergusonii, showing that the insertion has not affected sRNA production. Additionally, despite containing the large insertion, the sRNA appears to be functional because deletion of mgrR made E. fergusonii more susceptible to H2O2. The molecular details of MgrR's roles in H2O2defence are yet to be defined, but our results suggest that having an alternative function allowed the sRNA to be retained in E. fergusonii despite it sustaining a large, potentially disruptive mutation.

Dual lysine and N-terminal acetyltransferases reveal the complexity underpinning protein acetylation.

Protein acetylation is a highly frequent protein modification. However, comparatively little is known about its enzymatic machinery. N-α-acetylation (NTA) and ε-lysine acetylation (KA) are known to be catalyzed by distinct families of enzymes (NATs and KATs, respectively), although the possibility that the same GCN5-related N-acetyltransferase (GNAT) can perform both functions has been debated. Here, we discovered a new family of plastid-localized GNATs, which possess a dual specificity. All characterized GNAT family members display a number of unique features. Quantitative mass spectrometry analyses revealed that these enzymes exhibit both distinct KA and relaxed NTA specificities. Furthermore, inactivation of GNAT2 leads to significant NTA or KA decreases of several plastid proteins, while proteins of other compartments were unaffected. The data indicate that these enzymes have specific protein targets and likely display partly redundant selectivity, increasing the robustness of the acetylation process in vivo. In summary, this study revealed a new layer of complexity in the machinery controlling this prevalent modification and suggests that other eukaryotic GNATs may also possess these previously underappreciated broader enzymatic activities.

Compositional alterations of gut microbiota in nonalcoholic fatty liver disease patients: a systematic review and Meta-analysis.

BACKGROUND: Although imbalanced intestinal flora contributes to the pathogenesis of nonalcoholic fatty liver disease (NAFLD), conflicting results have been obtained for patient-derived microbiome composition analyses. A meta-analysis was performed to summarize the characteristics of intestinal microbiota at the species level in NAFLD patients. METHODS: Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) Statement, a completed search (last update: December 30, 2020) of databases was performed to identify eligible case-control studies detecting gut microbiota in NAFLD patients. The meta-analysis results are presented as the standard mean difference (SMD) and 95% confidence interval (CI). Bias controls were evaluated with the Newcastle-Ottawa Scale (NOS), funnel plot analysis, and Egger's and Begg's tests. RESULTS: Fifteen studies (NOS score range: 6-8) that detected the gut microbiota in the stools of 1265 individuals (577 NAFLD patients and 688 controls) were included. It was found that Escherichia, Prevotella and Streptococcus (SMD = 1.55 [95% CI: 0.57, 2.54], 1.89 [95% CI: 0.02, 3.76] and 1.33 [95% CI: 0.62, 2.05], respectively) exhibited increased abundance while Coprococcus, Faecalibacterium and Ruminococcus (SMD = - 1.75 [95% CI: - 3.13, - 0.37], - 9.84 [95% CI: - 13.21, - 6.47] and - 1.84 [95% CI, - 2.41, - 1.27], respectively) exhibited decreased abundance in the NAFLD patients compared with healthy controls. No differences in the abundance of Bacteroides, Bifidobacterium, Blautia, Clostridium, Dorea, Lactobacillus, Parabacteroides or Roseburia were confirmed between the NAFLD patients and healthy controls. CONCLUSIONS: This meta-analysis revealed that changes in the abundance of Escherichia, Prevotella, Streptococcus, Coprococcus, Faecalibacterium and Ruminococcus were the universal intestinal bacterial signature of NAFLD.

Isolation and characterization of chitinolytic bacterium, Escherichia fergusonii AMC01 from insectivorous bat, Taphozous melanopogon.

Chitinases are capable of hydrolyzing insoluble chitin into its oligo and monomeric parts and have received increased consideration because of their wide scope of biotechnological applications. The commercial application of microbial chitinase is appealing due to the relative ease of enormous production and to meet the current world demands. This study aimed at isolation and characterization of chitin degrading bacteria from the gut of Indian tropical insectivorous black-bearded tomb bat, Taphozous melanopogon. The isolated bacterial strains were characterized through biochemical analysis and nucleic acid-based approaches by 16S ribosomal RNA amplification and sequencing. The BLAST (Basic Local Alignment Search Tool) and phylogenetic analysis showed that the bacterial strain exhibited a close resemblance with Escherichia fergusonii. The chitinolytic activity of the E. fergusonii AMC01 was identified using supplemented colloidal chitin with agar medium. Compiling all, these findings would facilitate in constructing a database and presumably promote the use of E. fergusonii AMC01 as an efficient strain for the chitinase production.

Pan-Genome Reverse Vaccinology Approach for the Design of Multi-Epitope Vaccine Construct against Escherichia albertii.

Escherichia albertii is characterized as an emerging pathogen, causing enteric infections. It is responsible for high mortality rate, especially in children, elderly, and immunocompromised people. To the best of our knowledge, no vaccine exists to curb this pathogen. Therefore, in current study, we aimed to identify potential vaccine candidates and design chimeric vaccine models against Escherichia albertii from the analysis of publicly available data of 95 strains, using a reverse vaccinology approach. Outer-membrane proteins (n = 4) were identified from core genome as vaccine candidates. Eventually, outer membrane Fimbrial usher (FimD) protein was selected as a promiscuous vaccine candidate and utilized to construct a potential vaccine model. It resulted in three epitopes, leading to the design of twelve vaccine constructs. Amongst these, V6 construct was found to be highly immunogenic, non-toxic, non-allergenic, antigenic, and most stable. This was utilized for molecular docking and simulation studies against six HLA and two TLR complexes. This construct can therefore be used for pan-therapy against different strains of E. albertii and needs to be tested in vitro and in vivo.

Structural-functional characterization of recombinant Apolipoprotein A-I fromLabeo rohitademonstrates heat-resistant antimicrobial activity.

Apolipoprotein A-I is an anti-inflammatory, antioxidative, cardioprotective, anti-tumorigenic, and anti-diabetic in mammals. Apolipoprotein A-I also regulates innate immune defense mechanisms in vertebrates and invertebrates. Apolipoproteins A-I from mammals and several teleosts display antibacterial activities against Gram negative and Gram positive bacteria. The present study describes strategies to obtain high amounts of soluble purified recombinant Apolipoprotein A-I of Labeo rohita, an Indian major carp (rLrApoA-I). The study also reports its detailed structural and functional characterization i.e. antimicrobial activity against a number of important marine and fresh water bacterial pathogens. The rLrApoA-I was expressed in Escherichia coli BL21(DE3) pLysS expression host as a soluble protein under optimized conditions. The yield of purified rLrApoA-I was ~ 75 mg/L from soluble fraction using metal ion affinity chromatography. The authenticity of the rLrApoA-I was confirmed by MALDI-TOF-MS analysis. The secondary structure analysis showed rLrApoA-I to be predominantly alpha helical, an evolutionary conserved characteristic across mammals and teleosts. The purified rLrApoA-I exhibited antimicrobial activity as evident from inhibition of growth of a number of bacteria namely Aeromonas hydrophila, A. liquefaciens, A. culicicola, A. sobria, Vibrio harveyi, V. parahaemolyticus and Edwardsiella tarda in a dose-dependent manner. Minimum bactericidal concentration for A. liquefaciens, A. culicicola, and A. sobria, was determined to be 25 µg/ml or 0.81 µM whereas for A. hydrophila, E. tarda, V. parahaemolyticus and V. harveyi, it was determined to be 100 µg/ml or 3.23 µM. These data strongly suggest that recombinant ApoA-I from Labeo rohita could play a role in primary defense against fish pathogen. Further, at temperature ≥ 55 °C, though a loss in secondary structure was observed, no effect on its antibacterial activity was observed. This is of significance as the antibacterial activity is not likely to be lost even if the protein is subjected to high temperatures during transport.

A null model for microbial diversification.

Whether prokaryotes (Bacteria and Archaea) are naturally organized into phenotypically and genetically cohesive units comparable to animal or plant species remains contested, frustrating attempts to estimate how many such units there might be, or to identify the ecological roles they play. Analyses of gene sequences in various closely related prokaryotic groups reveal that sequence diversity is typically organized into distinct clusters, and processes such as periodic selection and extensive recombination are understood to be drivers of cluster formation ("speciation"). However, observed patterns are rarely compared with those obtainable with simple null models of diversification under stochastic lineage birth and death and random genetic drift. Via a combination of simulations and analyses of core and phylogenetic marker genes, we show that patterns of diversity for the genera Escherichia, Neisseria, and Borrelia are generally indistinguishable from patterns arising under a null model. We suggest that caution should thus be taken in interpreting observed clustering as a result of selective evolutionary forces. Unknown forces do, however, appear to play a role in Helicobacter pylori, and some individual genes in all groups fail to conform to the null model. Taken together, we recommend the presented birth-death model as a null hypothesis in prokaryotic speciation studies. It is only when the real data are statistically different from the expectations under the null model that some speciation process should be invoked.

Epidemiological Aspects of Escherichia albertii Outbreaks in Japan and Genetic Characteristics of the Causative Pathogen.

Zoonotic pathogen Escherichia albertii has been identified as the cause of several human disease outbreaks; however, factors such as the general symptoms and incubation period of E. albertii infection have yet to be defined. Therefore, we aimed to determine the unique aspects of E. albertii outbreaks in Japan and to examine the genetic characteristics of the causative pathogen. We studied all known E. albertii outbreaks that occurred in Japan up until 2015, which consisted of five confirmed outbreaks and one putative outbreak (Outbreaks 1-6). Outbreaks were re-examined based on personal communications between researchers in prefectural and municipal public health institutes, and through examination of any published study conducted at the time. Draft genome sequences of outbreak-associated E. albertii isolates were also generated. The most common symptom displayed by patients across the six episodes was watery diarrhea (>80%), followed by abdominal pain (50-84%) and fever (37.0-39.5°C) (26-44%). The estimated average incubation period of E. albertii infection was 12-24 h. We assumed that most of the outbreaks were foodborne or waterborne, with restaurant foods, restaurant water, and boxed lunches being the suspected transmission vehicles. Three of the six outbreak-associated E. albertii isolates possessed intact ETT2 regions, while the remaining isolates contained disrupted ETT2-encoding genes. Virulence gene screening revealed that more than half (44/70) of the tested genes were present in all 5 strains examined, and that each of the strains contained more than 1 gene from 14 out of the 21 groups of virulence genes examined in this study. The five E. albertii strains were classified into four of the five known phylogroups. Therefore, we determined that multiple E. albertii genotypes in Japan have the potential to cause outbreaks of diarrhea, abdominal pain, and/or fever following infection of a human host.

[Isolation and Identification of two Escherichia albertii strains in Shanxi Province, China].

Objective: To investigate the prevalence of Escherchia albertii in Shanxi province. Methods: The chicken intestines were enriched in EC broth. The eae gene was detected by PCR, and the eae-positive EC enrichments were inoculated in MacConkey agar plate. The eae-positive lactose non-fermenting isolates were presumed as Escherchia albertii, and then analyzed by triplex-PCR, 16S rDNA sequencing and MLST. Results: Two suspected Escherchia albertii were isolated from 250 samples of chicken intestines. It was identified as Escherchia albertii by phenotypic, specific genes,16S rDNA sequencing, and MLST analyses. The cytolethal distending toxin B (cdtB) showed positive by PCR,and they were clusted to Ⅱ/Ⅲ/Ⅴ group by sequencing. Conclusion: This study showed that the Escherchia albertii was existed in Shanxi province, China.

The Evasive Enemy: Insights into the Virulence and Epidemiology of the Emerging Attaching and Effacing Pathogen Escherichia albertii.

The diarrheic attaching and effacing (A/E) pathogen Escherichia albertii was first isolated from infants in Bangladesh in 1991, although the bacterium was initially classified as Hafnia alvei Subsequent genetic and biochemical interrogation of these isolates raised concerns about their initial taxonomic placement. It was not until 2003 that these isolates were reassigned to the novel taxon Escherichia albertii because they were genetically more closely related to E. coli, although they had diverged sufficiently to warrant a novel species name. Unfortunately, new isolates continue to be mistyped as enteropathogenic E. coli (EPEC) or enterohemorrhagic E. coli (EHEC) owing to shared traits, most notably the ability to form A/E lesions. Consequently, E. albertii remains an underappreciated A/E pathogen, despite multiple reports demonstrating that many provisional EPEC and EHEC isolates incriminated in disease outbreaks are actually E. albertii Metagenomic studies on dozens of E. albertii isolates reveal a genetic architecture that boasts an arsenal of candidate virulence factors to rival that of its better-characterized cousins, EPEC and EHEC. Beyond these computational comparisons, studies addressing the regulation, structure, function, and mechanism of action of its repertoire of virulence factors are lacking. Thus, the paucity of knowledge about the epidemiology, virulence, and antibiotic resistance of E. albertii, coupled with its misclassification and its ability to develop multidrug resistance in a single step, highlights the challenges in combating this emerging pathogen. This review seeks to synthesize our current but incomplete understanding of the biology of E. albertii.

Phenotypic and molecular characterization of Escherichia albertii: Further surrogates to avoid potential laboratory misidentification.

Escherichia albertii is an emerging gastrointestinal pathogen, related to Escherichia coli, which can be misidentified as enteropathogenic E. coli (EPEC) and enterohemorrhagic E. coli (EHEC), due to the presence of the eae gene in E. albertii. The aim of this study was to verify our hypothesis that E. coli cytolethal distending toxin-II (Eccdt-II) gene-positive E. coli is E. albertii and to accumulate the data regarding the bacteriological characteristics of E. albertii. For these purposes, we attempted to detect E. albertii in eae gene-positive bacteria previously identified as E. coli and to examine if re-identified E. albertii contained Eccdt-II-homologous gene and remaining eae gene-positive E. coli did not. A total of 373 eae gene-positive E. coli strains were analyzed by biochemical tests, multilocus sequence analysis and an E. albertii-specific PCR. The strains re-identified as E. albertii were also examined for the presence of cdt genes by using 32P-labled DNA probes, followed by their toxin-typing. Of the 373 strains, 17 were re-identified as E. albertii by three above-mentioned methods. Furthermore, all the 17 re-identified E. albertii possessed cdt genes highly homologous to Eccdt-II and Eacdt genes. Moreover, Eccdt-I or both Eccdt-I and stx2f genes were detected in two re-identified E. albertii strains. However, the remaining 356 strains did not carry such cdt genes. These data indicate that all re-identified E. albertii isolates specifically carried cdt genes homologous to Eccdt-II and Eacdt genes. We suggest that Eccdt-II gene-positive E. coli may be identical to E. albertii.

Transcriptional and posttranscriptional regulation of the locus of enterocyte effacement in Escherichia albertii.

The diarrheic bacterium Escherichia albertii is a recent addition to the attaching and effacing (A/E) morphotype of pathogens. A/E pathogens cause disease by tightly attaching to intestinal cells, destroying their actin-rich microvilli, and triggering re-localization and repolymerization of actin at the bacterial-host interface to form actin-filled membranous protrusions, termed A/E lesions, beneath the adherent bacterium. The locus of enterocyte effacement (LEE) is required for the biogenesis of these lesions. Whereas regulation of the LEE has been intensively investigated in EPEC and EHEC, it remains cryptic in E. albertii. In this study we characterized the very first transcriptional and posttranscriptional regulators of the LEE in this emerging pathogen. Our results suggest that Ler and GrlA globally activate transcription from the LEE, whereas GrlR negatively regulates the LEE. Additionally, we demonstrate that the RNA chaperone Hfq posttranscriptionally represses the LEE by specifically targeting the 5' UTR of grlR. In summary, our findings provide the very first glimpse of the regulatory landscape of the LEE in E. albertii - a bacterium that has been implicated in multiple diarrheal outbreaks worldwide.

Increased community-acquired upper urinary tract infections caused by extended-spectrum beta-lactamase-producing Escherichia coli in children and the efficacy of flomoxef and cefmetazole.

BACKGROUND: Urinary tract infections caused by extended-spectrum beta-lactamase-producing bacteria are increasing worldwide. At our hospital, the number of pediatric patients hospitalized because of an upper urinary tract infection has dramatically increased since 2016. In total, 60.5% of urinary tract infections are caused by extended-spectrum beta-lactamase-producing Escherichia coli. Such a high prevalence of extended-spectrum beta-lactamase-producing E. coli has not been detected previously in Japan. Therefore, we evaluated the clinical and bacteriologic characteristics and efficacy of antibiotics against upper urinary tract infections caused by E. coli in children. METHODS: This retrospective study surveyed 152 patients who were hospitalized in the pediatric department of Shimane Prefectural Central Hospital because of upper urinary tract infections caused by E. coli. Medical records were reviewed to examine patient characteristics. O antigens, antibiotic susceptibility, gene typing, and pulse-field gel electrophoresis were studied at the Shimane Prefectural Institute of Public Health and Environmental Science. RESULTS: Urine sample analyses showed extended-spectrum beta-lactamase types such as CTX-M-9 and plural virulence genes. We changed the primary antibiotic treatment to flomoxef or cefmetazole to treat upper urinary tract infections caused by Gram-negative bacilli. After changing treatment, the time to fever alleviation was significantly shortened. CONCLUSION: Extended-spectrum beta-lactamase-producing E. coli should be suspected in community-acquired upper urinary tract infections. Therefore, when treating patients, it is necessary to focus on antibiotic susceptibility and the prevalence of extended-spectrum beta-lactamase-producing bacteria found in each area. Flomoxef and cefmetazole are useful primary treatments for upper urinary tract infections caused by extended-spectrum beta-lactamase-producing E. coli.