Preferential use of carbon central metabolism and anaerobic respiratory chains in porcine extraintestinal pathogenic Escherichia coli during bloodstream infection

Dietary proteins are linked to the pathogenic Escherichia coli (E. coli) through the intestinal tract, which is the site where both dietary proteins are metabolized and pathogenic E. coli strains play a pathogenic role. Dietary proteins are degraded by enzymes in the intestine lumen and their metabolites are transferred into enterocytes to be further metabolized. Seven diarrheagenic E. coli pathotypes have been identified, and they damage the intestinal epithelium through physical injury and effector proteins, which lead to inhibit the digestibility and absorption of dietary proteins in the intestine tract. But the increased tryptophan (Trp) content in the feed, low-protein diet or milk fractions supplementation is effective in preventing and controlling infections by pathogenic E. coli in the intestine.

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Avian Pathogenic Escherichia coli (APEC): An Overview of Virulence and Pathogenesis Factors, Zoonotic Potential, and Control Strategies

Pathogens ◽

10.3390/pathogens10040467 ◽

2021 ◽

Vol 10 (4) ◽

pp. 467

Author(s):

Dipak Kathayat ◽

Dhanashree Lokesh ◽

Sochina Ranjit ◽

Gireesh Rajashekara

Keyword(s):

Escherichia Coli ◽

Current Status ◽

Neonatal Meningitis ◽

Clear Understanding ◽

Zoonotic Potential ◽

Secretion Systems ◽

Avian Pathogenic Escherichia Coli ◽

E Coli ◽

Pathogenic Escherichia Coli ◽

Tract Infections

Avian pathogenic Escherichia coli (APEC) causes colibacillosis in avian species, and recent reports have suggested APEC as a potential foodborne zoonotic pathogen. Herein, we discuss the virulence and pathogenesis factors of APEC, review the zoonotic potential, provide the current status of antibiotic resistance and progress in vaccine development, and summarize the alternative control measures being investigated. In addition to the known virulence factors, several other factors including quorum sensing system, secretion systems, two-component systems, transcriptional regulators, and genes associated with metabolism also contribute to APEC pathogenesis. The clear understanding of these factors will help in developing new effective treatments. The APEC isolates (particularly belonging to ST95 and ST131 or O1, O2, and O18) have genetic similarities and commonalities in virulence genes with human uropathogenic E. coli (UPEC) and neonatal meningitis E. coli (NMEC) and abilities to cause urinary tract infections and meningitis in humans. Therefore, the zoonotic potential of APEC cannot be undervalued. APEC resistance to almost all classes of antibiotics, including carbapenems, has been already reported. There is a need for an effective APEC vaccine that can provide protection against diverse APEC serotypes. Alternative therapies, especially the virulence inhibitors, can provide a novel solution with less likelihood of developing resistance.

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A TTP-incorporated scoring model for predicting mortality of solid tumor patients with bloodstream infection caused by Escherichia coli

Supportive Care in Cancer ◽

10.1007/s00520-021-06442-z ◽

2021 ◽

Author(s):

Qing Zhang ◽

Hao-Yang Gao ◽

Ding Li ◽

Chang-Sen Bai ◽

Zheng Li ◽

...

Keyword(s):

Escherichia Coli ◽

High Risk ◽

Bloodstream Infection ◽

Solid Tumor ◽

Prognostic Scores ◽

Risk Scores ◽

Youden Index ◽

Tumor Patients ◽

Scoring Model ◽

Significant Difference

Abstract Background Few mortality-scoring models are available for solid tumor patients who are predisposed to develop Escherichia coli–caused bloodstream infection (ECBSI). We aimed to develop a mortality-scoring model by using information from blood culture time to positivity (TTP) and other clinical variables. Methods A cohort of solid tumor patients who were admitted to hospital with ECBSI and received empirical antimicrobial therapy was enrolled. Survivors and non-survivors were compared to identify the risk factors of in-hospital mortality. Univariable and multivariable regression analyses were adopted to identify the mortality-associated predictors. Risk scores were assigned by weighting the regression coefficients with corresponding natural logarithm of the odds ratio for each predictor. Results Solid tumor patients with ECBSI were distributed in the development and validation groups, respectively. Six mortality-associated predictors were identified and included in the scoring model: acute respiratory distress (ARDS), TTP ≤ 8 h, inappropriate antibiotic therapy, blood transfusion, fever ≥ 39 °C, and metastasis. Prognostic scores were categorized into three groups that predicted mortality: low risk (< 10% mortality, 0–1 points), medium risk (10–20% mortality, 2 points), and high risk (> 20% mortality, ≥ 3 points). The TTP-incorporated scoring model showed excellent discrimination and calibration for both groups, with AUC being 0.833 vs 0.844, respectively, and no significant difference in the Hosmer–Lemeshow test (6.709, P = 0.48) and the chi-square test (6.993, P = 0.46). Youden index showed the best cutoff value of ≥ 3 with 76.11% sensitivity and 79.29% specificity. TTP-incorporated scoring model had higher AUC than no TTP-incorporated model (0.837 vs 0.817, P < 0.01). Conclusions Our TTP-incorporated scoring model was associated with improving capability in predicting ECBSI-related mortality. It can be a practical tool for clinicians to identify and manage bacteremic solid tumor patients with high risk of mortality.

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