Bloodstream Infections Caused by Extended-Spectrum Beta-Lactamase-Producing Escherichia coli in Patients with Liver Cirrhosis

Distribution and Genomic Characterization of Third-Generation Cephalosporin-Resistant Escherichia coli Isolated from A Single Family and Home Environment: A 2-Year Longitudinal Study

Third-generation cephalosporin-resistant Escherichia coli (CREC), particularly strains producing extended-spectrum β-lactamases (ESBLs), are a global concern. Our study aims to longitudinally assemble the genomic characteristics of CREC isolates from fecal samples from an index patient with recurrent CREC-related urinary tract infections and his family and swabs from his home environment 12 times between 2019 and 2021 to investigate the distribution of antibiotic resistance genes. CREC identified using the VITEK 2 were subjected to nanopore whole-genome sequencing (WGS). The WGS of 27 CREC isolates discovered in 137 specimens (1 urine, 123 feces, and 13 environmental) revealed the predominance of ST101 and ST131. Among these sequence types, bla_CTX-M (44.4%, n = 12) was the predominant ESBL gene family, with bla_CTX-M-14 (n = 6) being the most common. The remaining 15 (55.6%) isolates harbored bla_CMY-2 genes and were clonally diverse. All E. coli isolated from the index patient’s initial urine and fecal samples belonged to O25b:H4-B2-ST131 and carried bla_CTX-M-14. The results of sequence analysis indicate plasmid-mediated household transmission of bla_CMY-2 or bla_CTX-M-55. A strong genomic similarity was discovered between fecal ESBL-producing E. coli and uropathogenic strains. Furthermore, bla_CMY-2 genes were widely distributed among the CREC isolated from family members and their home environment.

Escherichia/Shigella, SCFAs, and Metabolic Pathways-The Triad That Orchestrates Intestinal Dysbiosis in Patients with Decompensated Alcoholic Cirrhosis from Western Mexico

Gut microbiota undergoes profound alterations in alcohol cirrhosis. Microbiota-derived products, e.g., short chain fatty acids (SCFA), regulate the homeostasis of the gut-liver axis. The objective was to evaluate the composition and functions of the intestinal microbiota in patients with alcohol-decompensated cirrhosis. Fecal samples of 18 patients and 18 healthy controls (HC) were obtained. Microbial composition was characterized by 16S rRNA amplicon sequencing, SCFA quantification was performed by gas chromatography (GC), and metagenomic predictive profiles were analyzed by PICRUSt2. Gut microbiota in the cirrhosis group revealed a significant increase in the pathogenic/pathobionts genera Escherichia/Shigella and Prevotella, a decrease in beneficial bacteria, such as Blautia, Faecalibacterium, and a decreased α-diversity (p < 0.001) compared to HC. Fecal SCFA concentrations were significantly reduced in the cirrhosis group (p < 0.001). PICRUSt2 analysis indicated a decrease in acetyl-CoA fermentation to butyrate, as well as an increase in pathways related to antibiotics resistance, and aromatic amino acid biosynthesis. These metabolic pathways have been poorly described in the progression of alcohol-related decompensated cirrhosis. The gut microbiota of these patients possesses a pathogenic/inflammatory environment; therefore, future strategies to balance intestinal dysbiosis should be implemented. These findings are described for the first time in the population of western Mexico.

Molecular Epidemiology of Escherichia coli Clinical Isolates from Central Panama

Escherichia coli represents one of the most common causes of community-onset and nosocomial infections. Strains carrying extended spectrum β-lactamases (ESBL) are a serious public health problem. In Central America we have not found studies reporting the molecular epidemiology of E. coli strains implicated in local infections, so we conducted this study to fill that gap. Materials and Methods: We report on an epidemiological study in two reference hospitals from central Panama, identifying the susceptibility profile, associated risk factors, and molecular typing of E. coli strains isolated between November 2018 and November 2019 using Pasteur’s Multilocus Sequence Typing (MLST) scheme. Results: A total of 30 E. coli isolates with antimicrobial resistance were analyzed, 70% of which came from inpatients and 30% from outpatients (p < 0.001). Two-thirds of the samples came from urine cultures. Forty-three percent of the strains were ESBL producers and 77% were resistant to ciprofloxacin. We identified 10 different sequence types (STs) with 30% of the ESBL strains identified as ST43, which corresponds to ST131 of the Achtman MLST scheme—the E. coli pandemic clone. Thirty-eight percent of the E. coli strains with the ESBL phenotype carried CTX-M-15. Conclusions: To the best of our knowledge, this is the first report confirming the presence of the pandemic E. coli clone ST43/ST131 harboring CTX-M-15 in Central American inpatients and outpatients. This E. coli strain is an important antimicrobial-resistant organism of public health concern, with potential challenges to treat infections in Panama and, perhaps, the rest of Central America.