Gut Pathogens最新文献

Objective: The gut is involved in the development of acute pancreatitis (AP). Increased focus is being given to the role of gut microbiota in the pathogenesis of AP. Nevertheless, there is currently no available evidence regarding the composition of fungal microorganisms in the intestines of patients with AP.

Methods: In this study, we sequenced ITS rRNA gene amplicons and examined the intestinal fungal microbiota in feces from 11 AP patients (the test group) and 15 healthy people (the control group). Additionally, we examined the relationship between fungus and clinical and biochemical markers.

Results: Results showed a decline in alpha diversity in AP patients. The overall fungal microbiota in the test group was significantly different from that of the control group (P < 0.05). In both groups, the fecal fungal microbiota was dominated by Ascomycota and Basidiomycota phyla. At the genus level, the abundance of Candida was significantly higher in the test group and the abundances of Penicillium, Auricularia, unclassified Eurotiomycetes, Epicoccum and Vishniacozyma were significantly lower. Furthermore, AP patients had a significant decrease in the GMHI score and a significant increase in the MDI index. The co-abundance networks of gut fungus in AP patients showed more interactions and mostly positive correlations than in the control group. There was a strong positive link between Aspergillus and WBC counts, while There was a strong link between unclassified Rozellomycota and IL-6.

Conclusion: Our study provides the first empirical evidence that AP patients have different fecal fungal microbiota, which raises the possibility that mycobiota contribute to the etiology and progression of AP.

Background: Sepsis represents the most prevalent infectious complication and the primary cause of mortality in myeloproliferative neoplasms (MPN). The risk of sepsis and the difficulty of treatment are significantly increased in MPN patients due to the need for immunomodulators and antibiotics.

Case presentation: On June 9, 2023, a 69-year-old male was admitted to the hospital. Following a battery of tests, the diagnosis of sepsis due to Escherichia coli was ultimately established. The patient was administered amoxicillin clavulanate potassium intravenously. In light of the patient's recurrent sepsis and the likelihood that the source of infection is the intestinal tract, we advised that the patient undergo washed microbiota transplantation (WMT) via a colonic transendoscopic enteral tube (TET).

Conclusions: WMT as the new method of fecal microbiota transplantation (FMT) successfully cured the recurrent sepsis in this case, indicating the novel option for challenging the refractory or serious infections.

Background: Maintaining gut microbial homeostasis is crucial for human health, as imbalances in the gut microbiota (GM) can lead to various diseases, including metabolic syndrome (MS), exacerbated by the use of antipsychotic medications such as olanzapine (OLZ). Understanding the role of the GM in OLZ-induced MS could lead to new therapeutic strategies. This study used metagenomic analysis to explore the impact of OLZ on the GM composition and examined how probiotics can mitigate its adverse effects in a rat model. Changes in weight, blood pressure, and lipid levels, which are key parameters defining MS, were assessed. Additionally, this study investigated serotonin, dopamine, and histopathological changes to explore their possible link with the microbiota-gut-brain axis (MGBA).

Results: OLZ had an antagonistic effect on serotonin and dopamine receptors, and it was consistently found to alter the composition of the GM, with an increase in the relative abundance (RA) of the Firmicutes/Bacteroidetes phyla ratio and TM7 genera, indicating that the anticommonsal action of OLZ affects appetite and energy expenditure, contributing to obesity, dyslipidemia and increased blood pressure, which are core components of MS. Hepatic steatosis and intestinal damage in OLZ-treated rat tissues further indicate its role in MS. Conversely, the administration of probiotics, either alone or in combination with OLZ, was found to mitigate these OLZ-induced symptoms of MS by altering the GM composition. These alterations included increases in the abundances of the taxa Bacteroidetes, Actinobacteria, Prevotella, Blautia, Bacteroides, Bacteroidales, and Ruminococcaceae and a decrease in Firmicute abundance. These changes helped maintain gut barrier integrity and modulated neurotransmitter levels, suggesting that probiotics can counteract the adverse metabolic effects of OLZ by restoring the GM balance. Moreover, this study highlights the modulation of the MGBA by OLZ as a potential mechanism through which probiotics modulate serotonin and dopamine levels, influencing metabolic health.

Conclusion: These findings emphasise the significant impact of OLZ on the GM and its contribution to MS. These findings suggest that interventions targeting the GM, such as probiotics, could mitigate the metabolic side effects of OLZ. Future research should focus on developing integrative treatment approaches that consider the health of the gut microbiome in managing antipsychotic-induced adverse effects.

Bacterial infections leading to bacteremia and septicemic shock constitute an emerging public health concern globally, especially in areas where sanitation is poor and safe drinking water is scarce. Enteric pathogens such as Vibrio cholerae are responsible for many deaths caused by contaminated food and water in these areas. While cholera is the prominent clinical threat posed by V. cholerae, outcomes like bacteremia turning into sepsis and associated morbidity and mortality have been increasing globally in recent times. Here, we report an alarming case of fatal sepsis with a probable association of V. cholerae bacteremia in Bangladesh. In September 2023, a 30-year-old man with a pre-condition of beta-thalassemia presented to a tertiary care hospital with acute diarrhea, abdominal pain, nausea, and fever and died within 36 h of admission with acute cholecystitis, metabolic acidosis, acute kidney injury, pancytopenia, and refractory septic shock with multi-organ dysfunction syndrome. Blood culture detected V. cholerae, which was further characterized as hemolytic, carrying the hemolysin gene and genes for the virulence factor type-three secretion system. The isolate was confirmed as V. cholerae non-O1/O139 (NOVC), which differed in genetic properties from the few contemporary NOVC isolates associated with diarrheal cases in Bangladesh. To manage the diarrhea and septicemic condition, the patient was treated empirically with metronidazole and meropenem. However, antibiotic susceptibility testing showed the strain was susceptible to all the routinely prescribed drugs for V. cholerae infections. To the best of our knowledge, this investigation provides the first molecular description of a fatal case of V. cholerae-associated bacteremia in Bangladesh and underscores the need for comprehensive investigations on bacterial septicemia to prevent future casualties.

Background: Enterohemorrhagic Escherichia coli (EHEC), a group of enteric pathogenic bacteria that is a major cause of human diarrheal disease, must interact with the diverse intestinal microbiome during colonization and subsequently overcome the environmental challenges to survive and cause disease. While this relationship, and how the microbiome modulates infection of EHEC, has been studied, it is less understood how the microbiome is impacted during treatment for an EHEC infection. One area that is notably lacking in knowledge is how vaccination can impact the intestinal microbiome composition, and therefore, influence vaccine efficacy. We previously developed vaccine formulations consisting of gold nanoparticles (AuNPs) conjugated to various EHEC antigens and tested them in mice models using both EHEC and its murine counterpart Citrobacter rodentium. The goal of this study was to evaluate the relationship between these EHEC vaccines and their effects on the gut microbiome.

Results: We found that immunization with the vaccines or adjuvant-only control did not lead to major alterations in the composition of the fecal microbiome; however, there were measurable variations in individual mice within the same vaccine group housed in separate cages. Also, immunization with one vaccine (AuNP-EscC) prevented both a decrease in the diversity of the fecal microbiome and an increase in detectable C. rodentium following infection compared to control animals.

Conclusions: Overall, our small study argues in favor of evaluating the intestinal microbiome during vaccine development not just for EHEC, but for other enteric pathogens.

Background: Giardia duodenalis (G. duodenalis) is an intestinal protozoan parasite of human and animal hosts. The present study investigated and compared the assemblages of G. duodenalis-infected faecal samples in patients on corticosteroid therapy (POCT) and control patients-not on corticosteroid therapy (CONT) and differentiated its assemblages and/or sub-assemblages' relationship with associated risk factors.

Methods: Utilizing multi-locus sequence typing (MLST) with three loci targeted-triosephosphate isomerase (tpi), ꞵ-giardin (bg), and glutamate dehydrogenase (gdh)-G. duodenalis isolated from POCT and CONT were analyzed. Risk factors linked with Giardia infection and its assemblages were investigated.

Results: In total, 52 G. duodenalis-infected patients were enrolled: 21 POCT and 31 CONT. The mean age was 12.3 years, the majority were male (59.6%), and 73.1% lived in rural areas. The POCT group was 36 times more likely than the CONT group to have a concurrent parasitic infection. About 73% (38/52) of Giardia samples were genotyped and/or sub-genotyped in at least one of the three loci. MLST identified sixteen isolates (42.0%) as assemblage B, ten isolates (26.3%) as assemblage A, and twelve isolates (31.6%) as a mixed infection of A + B and B + E. Most individuals of the POCT group were infected with G. duodenalis assemblage A while most of the CONT group were infected with assemblage B. Sub-assemblage AII was identified by phylogenetic analysis in the isolates of both groups under investigation.

Conclusion: This research advances giardiasis epidemiology in Arab Republic of Egypt (ARE) and reflects how corticosteroid-treated patients differ from those non-treated in Giardia assemblage pattern and their susceptibility to concomitant infection. Overall, Giardia assemblage patterns in this research populations reflect anthroponotic and zoonotic transmission, emphasizing the importance of public health policy and giardiasis prevention of illness transmission, particularly among those on corticosteroid therapy in ARE.

Background: Colistin resistance significantly constrains available treatment options and results in the emergence of pandrug-resistant (PDR) strains. Treating PDR infections is a major public health issue. A promising solution lies in using colistin-based combinations. Despite the availability of in vitro data evaluating these combinations, the in vivo studies remain limited.

Results: Thirty colistin-resistant Klebsiella pneumoniae (ColRKp) isolates were collected from hospitalized patients. Colistin resistance was detected using broth microdilution, and antimicrobial susceptibility was tested using the Kirby-Bauer method against 18 antibiotics. Extremely high resistance levels were detected, with 17% of the isolates being PDR. Virulence profiling, assessed using Anthony capsule staining, the string test, and the crystal violet assay, indicated the predominance of non-biofilm formers and non-hypermucoid strains. The isolates were screened for mcr genes using polymerase chain reaction. Whole-genome sequencing (WGS) and bioinformatics analysis were performed to characterize the genomes of PDR isolates. No plasmid-borne mcr genes were detected, and WGS analysis revealed that PDR isolates belonged to the high-risk clones: ST14 (n = 1), ST147 (n = 2), and ST383 (n = 2). They carried genes encoding extended-spectrum β-lactamases and carbapenemases, bla_CTX-M-15 and bla_NDM-5, on conjugative IncHI1B/IncFIB plasmids, illustrating the convergence of virulence and resistance genes. The most common mechanism of colistin resistance involved alterations in mgrB. Furthermore, deleterious amino acid substitutions were also detected within PhoQ, PmrC, CrrB, ArnB, and ArnT. Seven colistin-containing combinations were compared using the checkerboard experiment. Synergy was observed when combining colistin with tigecycline, doxycycline, levofloxacin, ciprofloxacin, sulfamethoxazole/trimethoprim, imipenem, or meropenem. The efficacy of colistin combined with either doxycycline or levofloxacin was assessed in vitro using a resistance modulation assay, and in vivo, using a murine infection model. In vitro, doxycycline and levofloxacin reversed colistin resistance in 80% and 73.3% of the population, respectively. In vivo, the colistin + doxycycline combination demonstrated superiority over colistin + levofloxacin, rescuing 80% of infected animals, and reducing bacterial bioburden in the liver and kidneys while preserving nearly intact lung histology.

Conclusions: This study represents the first comparative in vitro and in vivo investigation of the efficacy of colistin + doxycycline and colistin + levofloxacin combinations in clinical PDR ColRKp isolates characterized at a genomic level.

The composition of human gut microbiota is dominated by bacteria which have been extensively studied. The role of intestinal eukaryote microorganisms like Blastocystis, however, remains under investigation. Moreover, the potential impact on gut health related to Blastocystis presence was primarily investigated in symptomatic individuals mainly from industrialized countries, and appears to be mostly beneficial to the host microbiota. Data from surveys conducted in underdeveloped countries with higher prevalence and from asymptomatic individuals could therefore be valuable. The aim of this preliminary study was to analyze the composition of the gut microbiota in relation to the protozoa Blastocystis ST1 and ST2 and Entamoeba hartmanni carriage in asymptomatic subjects living in a semi-urban area of Côte d'Ivoire to add data into the ongoing debate on the role of Blastocystis in host health. The amplification of the V3 and V4 regions of bacterial 16S rDNA genes was performed to obtain the gut microbiota composition, and differential analyses on alpha and beta diversity were performed from the phylum to genus taxonomic level. The analysis revealed that individuals positive for both protozoa exhibited higher alpha and beta diversity compared to those who tested negative. Additionally, their bacterial composition showed a reduction in Bacteroides and an increase in Prevotella 9. Relative abundances of some OTUs, particularly Faecalibacterium, observed in individuals who tested positive for protozoa, were correlated with a good state of health of the gut microbiota. Blastocystis ST1 and ST2 associated with E. hartmanni thus appeared to be related to a state of intestinal eubiosis.

Background: Peptic ulcers are a common gastrointestinal disease that could cause death when combined with bleeding. The aim of this study was to identify risk factors for peptic ulcer bleeding (PUB) recurrence after the initial episode.

Methods: This retrospective study analyzed medical records of PUB patients who were admitted through the emergency department between January 1, 2020, and December 31, 2022. A multivariate logistic regression model was used to identify independent risk factors predicting readmission due to recurrent PUB within one year.

Results: A total of 775 PUB inpatient samples were collected, among which 172 and 603 were placed respectively in the readmission group and non-readmission group. Multivariate analysis indicated that PUB inpatients who were aged 70 or above (OR = 1.62, 95% CI: 1.06-2.47), had more severe ulcers (Forrest 1a, 1b, 2a, or 2b) (OR = 2.41, 95% CI:1.57-3.71), had a CCI score of 3 or higher (OR = 2.25, 95% CI:1.45-3.50), had a medical history of peptic ulcers (OR = 3.87, 95% CI:2.56-5.85), had a medical history of cardiovascular disease (CVD) (OR = 2.31, 95% CI:1.53-3.50), or had an international normalized ratio (INR) > 1.2 on admission (OR = 2.14, 95% CI:1.28-3.57) were respectively more likely to be readmitted within a year due to PUB than those who were under the age of 70, had less severe ulcers (Forrest 2c or 3), had a CCI score of less than 3, had no medical history of peptic ulcers, had no medical history of CVD, or had admission INR ≤ 1.2.

Conclusion: This study confirmed that age (≥70 years), Forest classification (Forrest 1a, 1b, 2a, or 2b), multiple comorbidities, a medical history of peptic ulcers, a medical history of CVD, and admission INR > 1.2 were independent risk factors for patient readmission within a year due to recurrent PUB.

Background: Antimicrobial resistance (AMR) is one of the most pressing global public health challenges; in particular, the rapid dissemination of carbapenem-resistant Enterobacterales (CRE) is emerging as a significant concern worldwide. Flies, serving as carriers of pathogens, pose a potential threat in the transmission of antibiotic-resistant bacteria (ARB) between animals and humans. The aim of this study was to evaluate and reveal the potential risk of AMR spread by flies.

Methods: A total of 450 flies were collected from four farms, four rural areas, and four urban areas in Dengfeng, Henan, China. To select CRE strains on the surface of flies, three flies sampled from the same geographical location were arbitrarily selected and placed into one tube of brain heart infusion broth (BHI), and the supernatant was screened using CHROMagar™ mSuperCARBA culture medium. Different colors and shapes of colonies were identified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and 16S rRNA sequencing. Antimicrobial susceptibility testing for CRE strains was performed using broth microdilution. All CRE strains were whole-genome sequenced. Short-read sequencing was performed using MGISEQ-2000 and long-read sequencing was conducted using GridION.

Results: Totally, 150 BHI tubes were screened for CRE strains, and 33 strains were identified as CRE positive. In 24 mSuperCARBA plates, only one species of CRE strain was isolated from each plate. In three plates, two different species of CRE strains were identified in each plate. In one plate, three different species of CRE strains were simultaneously isolated. Carbapenem resistance genes were detected in 81.8% of CRE strains, and bla_NDM-1 was predominant (66.7%). No significant correlations between carbapenem-resistant phenotypes and carbapenem resistance genes were observed. The complete genomes of all 33 strains were obtained. Genome analysis revealed that clonal transmission events may have occurred among different farms and rural areas. Phylogenetic analysis revealed that bla_NDM-1 IncFII plasmids could break bacterial species barrier for cross-host transmission in diverse areas.

Conclusions: To understand and control the transmission of AMR from the perspective of One Health, it is imperative to enhance surveillance of ARB, antibiotic resistance genes, and antibiotic-resistant plasmids in flies.