colistin and Enterocolitis

Reports about acquired resistance to colistin in different bacteria species are increasing, including E. coli of animal origin, but reports of resistance in wild S. enterica of different serotypes from swine are not found in the literature. Results obtained with one hundred and twenty-six E. coli strains from diseased swine and one hundred and twenty-four S. enterica strains from diseased and carrier swine showed a frequency of 6.3% and 21% of colistin-resistant strains, respectively. When comparing the disk diffusion test with the agar dilution test to evaluate the strains, it was confirmed that the disk diffusion test is not recommended to evaluate colistin resistance as described previously. The colistin MIC 90 and MIC 50 values obtained to E. coli were 0.25 μg/mL and 0.5 μg/mL, the MIC 90 and MIC 50 to S. enterica were 1 μg/mL and 8 μg/mL. Considering the importance of colistin in control of nosocomial human infections with Gram-negative multiresistant bacteria, and the large use of this drug in animal production, the colistin resistance prevalence in enterobacteriaceae of animal origin must be monitored more closely.

Topics: Animals; Anti-Bacterial Agents; Brazil; Colistin; Disk Diffusion Antimicrobial Tests; Drug Resistance, Bacterial; Enterocolitis; Escherichia coli; Feces; Salmonella enterica; Swine; Swine Diseases

The pathogenesis of inflammatory bowel disease involves dysfunctional mucosal immune responses to commensal bacteria in genetically predisposed hosts. Interactions between host cells and bacteria are complicated, making it a challenge to assess their relative contribution to intestinal pathology. We developed a zebrafish model of enterocolitis to study these interactions.. Enterocolitis was induced by intrarectal administration of the hapten oxazolone in adult wild-type and myeloperoxidase-reporter transgenic zebrafish in the presence or absence of antibiotics. Intestinal inflammation was evaluated by histological and flow cytometry analyses and cytokine profiling with quantitative real-time polymerase chain reaction. Changes in the composition of the intestinal microbiota following antibiotic administration were assessed by 16SrRNA sequencing and bacterial load was quantified by culture on nonselective media (colony-forming units).. In zebrafish, the infiltrate and severity of oxazolone-induced enterocolitis are influenced by the composition of the microbiota. Inflammation is characterized by granulocyte influx; epithelial damage; goblet cell depletion; and increased expression of interleukin-1beta, tumor necrosis factor-alpha, and interleukin-10. Zebrafish given vancomycin had bacterial populations dominated by Fusobacteria and reduced enterocolitis scores, intestinal damage, and percentages of infiltrating neutrophils and eosinophils. In contrast, zebrafish given colistin sulphate had a predominance of proteobacteria and reduced eosinophil and lymphocyte infiltration, but enterocolitis scores were not reduced.. In zebrafish with oxazolone-induced enterocolitis, components of the intestinal microbiota affect the severity and composition of the intestinal infiltrate.

Topics: Adjuvants, Immunologic; Animals; Anti-Bacterial Agents; Colistin; Disease Models, Animal; Enterocolitis; Intestines; Oxazolone; Vancomycin; Zebrafish

Topics: Candidiasis; Colistin; Diarrhea; Diarrhea, Infantile; Enterocolitis; Escherichia coli Infections; Humans; Infant; Intestines; Toxicology

Topics: Adolescent; Anti-Bacterial Agents; Child; Colistin; Colitis; Drug Therapy; Enterocolitis; Erythromycin; Escherichia coli Infections; Gastroenteritis; Oxytetracycline; Staphylococcal Infections

Topics: Anti-Bacterial Agents; Child; Colistin; Colitis; Enterocolitis; Gastroenteritis; Humans; Infant