Microbiota intestinal y colitis ulcerosa, abordaje metagenómico

Abstract

There have been described changes in fecal microbiota composition in patients with UC with inflammatory activity versus healthy individual, but it is not clear whether the dysbiotic changes are secondary to the disease itself or, on the contrary, may play a role in the pathophysiology of intestinal inflammation. The literature is controversial as to whether these changes are maintained during remission periods. The first part of this thesis tries to establish whether the dysbiotic changes disappear during the remission periods and the stability of the microbiota is completely restored. For this purpose, a population of subjects included in the METAHIT study, composed with patients with ulcerative colitis in remission with high outbreak rate, low outbreak rate, related relatives and healthy volunteers are studied. Under the hypothesis that ulcerative colitis has permanent intestinal dysbiosis changes that can be demonstrated during periods of remission, we compare the fecal microbiota composition of UC patients in remission with that of healthy individuals using high throughput sequencing techniques. We appreciate that there is a gradation in bacterial gene count among patients with CU in remission, related relatives and healthy volunteers. The second part of this thesis, tries to establish if the fecal dysbiosis are due to a greater colonic transit. To this purpose, it is analyzed whether the colonic cleansing with PEG induces permanent changes in the composition of the intestinal microbiota of healthy individuals and patients with ulcerative colitis in remission, through the application of 16S rRNA gene sequencing techniques. The results indicate that after the administration of the PEG there is a loss in the diversity of the microbiota that tends to recover at 2 months.

Date of Award	21 Sept 2017
Original language	Spanish
Supervisor	Francisco Guarner Aguilar (Director) & Jaume Vilaseca Momplet (Director)