Presence of eubacteria in biopsies from Crohn's disease inflammatory lesions as determined by 16S rRNA gene-based PCR.

The aim of this study was to search for putative microbial agents in Crohn' s disease (CD) tissues by bacterial broad-range 16S rDNA PCR combined with genus- and species-specific DNA hybridisation analysis, Biopsies taken both surgically and endoscopically from the terminal ileum of 11 CD patients an d 11 control patients were investigated. Significant amounts of eubacteria were demonstrated in biopsies taken endoscopically from both affected and u naffected individuals; the biopsies taken at surgery from control patients were negative. Three of five biopsies taken surgically from CD patients har boured Helicobacter spp.-. Mycobacterium paratuberculosis-, Listeria monocy togenes- and Escherichia coli-like 16S rDNA sequences. These findings show the importance of the sampling method chosen when combined with molecular t yping of eubacteria in intestinal tissues,The mixed bacterial flora found i n the surgical biopsies from CD patients supports the idea that the enteric microflora enters primary lesions where secondary bacterial colonisers may elicit a chronic inflammatory syndrome.