Dataset Information

Enterohepatic helicobacter in ulcerative colitis: potential pathogenic entities?

ABSTRACT:

Background

Changes in bacterial populations termed "dysbiosis" are thought central to ulcerative colitis (UC) pathogenesis. In particular, the possibility that novel Helicobacter organisms play a role in human UC has been debated but not comprehensively investigated. The aim of this study was to develop a molecular approach to investigate the presence of Helicobacter organisms in adults with and without UC.

Methodology/principal findings

A dual molecular approach to detect Helicobacter was developed. Oligonucleotide probes against the genus Helicobacter were designed and optimised alongside a validation of published H. pylori probes. A comprehensive evaluation of Helicobacter genus and H. pylori PCR primers was also undertaken. The combined approach was then assessed in a range of gastrointestinal samples prior to assessment of a UC cohort. Archival colonic samples were available from 106 individuals for FISH analysis (57 with UC and 49 non-IBD controls). A further 118 individuals were collected prospectively for dual FISH and PCR analysis (86 UC and 32 non-IBD controls). An additional 27 non-IBD controls were available for PCR analysis. All Helicobacter PCR-positive samples were sequenced. The association between Helicobacter and each study group was statistically analysed using the Pearson Chi Squared 2 tailed test. Helicobacter genus PCR positivity was significantly higher in UC than controls (32 of 77 versus 11 of 59, p?=?0.004). Sequence analysis indicated enterohepatic Helicobacter species prevalence was significantly higher in the UC group compared to the control group (30 of 77 versus 2 of 59, p<0.0001). PCR and FISH results were concordant in 74 (67.9%) of subjects. The majority of discordant results were attributable to a higher positivity rate with FISH than PCR.

Conclusions/significance

Helicobacter organisms warrant consideration as potential pathogenic entities in UC. Isolation of these organisms from colonic tissue is needed to enable interrogation of pathogenicity against established criteria.

SUBMITTER: Thomson JM

PROVIDER: S-EPMC3044171 | biostudies-literature | 2011 Feb

REPOSITORIES: biostudies-literature

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Publications

Enterohepatic helicobacter in ulcerative colitis: potential pathogenic entities?

Thomson John M JM Hansen Richard R Berry Susan H SH Hope Mairi E ME Murray Graeme I GI Mukhopadhya Indrani I McLean Mairi H MH Shen Zeli Z Fox James G JG El-Omar Emad E Hold Georgina L GL

PloS one 20110223 2

<h4>Background</h4>Changes in bacterial populations termed "dysbiosis" are thought central to ulcerative colitis (UC) pathogenesis. In particular, the possibility that novel Helicobacter organisms play a role in human UC has been debated but not comprehensively investigated. The aim of this study was to develop a molecular approach to investigate the presence of Helicobacter organisms in adults with and without UC.<h4>Methodology/principal findings</h4>A dual molecular approach to detect Helicob ...[more]

PMID: 21383845

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Dataset Information

Enterohepatic helicobacter in ulcerative colitis: potential pathogenic entities?

Background

Methodology/principal findings

Conclusions/significance

Publications

Enterohepatic helicobacter in ulcerative colitis: potential pathogenic entities?

Similar Datasets

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