Tuesday, November 06, 2012
Crohn's disease in children may start from bacteria
Crohn's disease in children may start from bacteria
Nov 5, 2012
Certain types of bacteria may cause and maintain Crohn’s disease, according to a new study.
Crohn’s causes inflammation of the digestive system. Symptoms include abdominal pain, diarrhea, weight loss, joint pain, skin problems, fever and bleeding from the rectum.
In this study, researchers found that 19 children newly diagnosed with Crohn’s disease had different levels of a group of bacteria called proteobacteria, which include E. coli and Campylobacter concisus.
The researchers also checked bacteria levels in 21 healthy children.
Patients with mild Crohn’s had higher levels of proteobacteria in their intestinal tracts than those with moderate to severe disease and children without Crohn’s disease.
This suggests that these types of bacteria may play a role in causing the disease, said study principal investigator Hazel Mitchell of the University of New South Wales, in Australia.
The findings may help lead to new treatments that target intestinal bacteria.
The study was published in the October issue of the Journal of Clinical Microbiology.
“We deliberately chose to examine children newly diagnosed with Crohn’s disease, as we thought this would increase our chances of detecting species that may be involved in initiating Crohn’s disease,” Mitchell said in a journal news release.
Mitchell explained that factors that can affect bacteria in the intestinal tract — such as the use of antibiotics or anti-inflammatory drugs, smoking or alcohol consumption — are less likely to be present in children than in adults.
Labels: abdominal pain, bacteria, bleeding, Crohn's disease, diarrhea, digestive system, fever, inflammation, joint pain, Proteobacteria, skin problems, weight loss
# posted by Pat O'Connor @ 8:12 AM
Saturday, November 03, 2012
Disruption of the Human Gut Microbiota following Norovirus Infection.
Disruption of the Human Gut Microbiota following Norovirus Infection.
2012
Source
Department of Internal Medicine, Division of Pulmonary and Critical Care Medicine, University of Michigan Medical School, Ann Arbor, Michigan, United States of America ; Department of Internal Medicine, Division of Infectious Diseases, University of Michigan Medical School, Ann Arbor, Michigan, United States of America.
Abstract
The gut microbiota, the collection of all bacterial members in the intestinal tract, plays a key role in health. Disruption of the indigenous microbiota by a variety of stressors, including antibiotic therapy and intestinal infections, is associated with multiple health problems. We sought to determine if infection with Norovirus disrupts the gut microbiota. Barcoded pyrosequencing of the 16S rRNA-encoding gene was used to characterize the stool microbiota in Norovirus-infected human patients (n = 38). While the microbiota in most infected patients (n = 31) resembled that seen in uninfected healthy controls, a minority of patients (n = 7) possessed a significantly altered microbiota characterized by reduced relative numbers of Bacteriodetes and a corresponding increase in Proteobacteria. In these patients, the increase in Proteobacteria was due to a single operational taxonomic unit (OTU) of Escherichia coli. We cultured E. coli from Norovirus-infected patients and characterized them using PCR-ribotyping and virulence factor analysis. Multiple ribotypes were encountered, but none possessed typical virulence factors commonly carried by enteropathogenic E. coli strains. Microbiota disruption and elevated Proteobacteria were not significantly correlated to patient age, gender, sampling time following illness onset, or overall gut inflammation. These results demonstrate that some patients have a disrupted microbiota following Norovirus infection, and therefore may be at elevated risk for long-term health complications.
Labels: .Barcoded pyrosequencing, health complications, Human Gut Microbiota, ibotypes, Norovirus Infection, Proteobacteria
# posted by Pat O'Connor @ 10:55 AM
