Comparison of faecal microbiota in Blastocystis-positive and Blastocystis-negative irritable bowel syndrome patients

Abstract

BackgroundWe investigated whether the carriage of Blastocystis in IBS patients was associated with differences in the faecal microbiota. Forty patients with diarrhoea-predominant IBS (26 Blastocystis-positive and 14 Blastocystis-negative) and 57 healthy controls (HC) (42 Blastocystis-positive and 15 Blastocystis-negative) submitted faecal samples for metataxonomic analysis of the 16S ribosomal RNA gene. Differences in the relative abundance of bacteria in these IBS and HC groups were evaluated from phylum to genus level.ResultsSignificant changes were observed in two dominant phyla in IBS patients, regardless of Blastocystis infection status, namely a rise in Firmicutes and a statistically significant reduction in relative abundance of Bacteroidetes (with a threefold increase in the Firmicutes to Bacteoridetes ratio). Significant differences at genus level in IBS subjects compared to HC were also observed for many bacterial species. However, further clinical subgroup analysis of Blastocystis-positive and Blastocystis-negative subjects, regardless of symptoms, showed no significant differences at the phylum or genus level in IBS-P compared to IBS-N.ConclusionsSignificant differences in the faecal microbiota between diarrhoea-predominant IBS patients and healthy controls were confirmed, but the carriage of Blastocystis did not significantly alter the faecal microbiota. If Blastocystis-positive patients represent a separate clinical subtype of IBS, this group is not identified by changes in the microbiota.Electronic supplementary materialThe online version of this article (doi:10.1186/s40168-016-0191-0) contains supplementary material, which is available to authorized users.

A Clostridia-rich microbiota contributes to increased excretion of bile acids in diarrhea-predominant irritable bowel syndrome

“…Scrutinizing the linkage of microbial signature with the IBS subtype, varied results have been reported across studies 26 , a reduced microbial diversity and increased F/B ratio were more frequently found. 45 47 48 Our study did find an increased F/B ratio in this IBS-D cohort, but with no difference in the microbial richness. Notably, proportions of taxa were significanlty altered shown in BA + IBS-D patients, not in all IBS-D population, illustrating abnormal BA excretion closely related to differentiation of gut microbiota among the IBS-D population.…”

Predictable modulation of cancer treatment outcomes by the gut microbiota

“…S3C). Compared with healthy individuals, a higher F/B ratio has also been observed in patients with irritable bowel syndrome (IBS), hypertension, autism, and chronic fatigue syndrome in case control studies [20][21][22][23]. Taken together, these comparisons above suggest that cancer treatments may not significantly disrupt the patients' individual signatures of gut microbiota; however, the cancer patients have distinct gut microbiota features compared to the healthy cohort.…”

Gut microbiota composition and functional prediction in diarrhea-predominant irritable bowel syndrome

“…At phylum level, Firmicutes and Fusobacteria decreased signi cantly, and Proteobacteria increased signi cantly in IBS-D patients. In reviewing the literature, decreased levels of Firmicutes and increased levels of Bacteroidetes were found in 2 studies [20,21], one in China, but 4 studies [22,23,24,25] reported opposite results, and 3 studies [24,25,26] found that Proteobacteria were increased. In assessing genus level, Enterobacteriaceae signi cantly increased, and Alloprevotella, Fusobacterium signi cantly decreased.…”