title: Comparison of faecal microbiota in Blastocystis-positive and Blastocystis-negative irritable bowel syndrome patients.
abstract: We 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.
  
  
  
  Significant 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.
  
  
  
  Significant 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.
authors: School of Veterinary Science, The University of Queensland, Gatton Campus, Brisbane, Queensland, 4343, Australia. robyn@tgclinic.com.au.|Toowoomba Gastroenterology Clinic, Suite 105 Medici Medical Centre, 15 Scott St, Toowoomba, QLD, 4350, Australia. robyn@tgclinic.com.au.
authors: Robyn
authors: 0000-0001-8389-2718
authors: R
authors: Nagel
authors: Faculty of Veterinary and Agricultural Sciences, University of Melbourne, Parkville, Melbourne, Victoria, 3052, Australia.
authors: Rebecca J
authors: RJ
authors: Traub
authors: School of Pathology and Laboratory Medicine, University of Western Australia, Crawley, Western Australia, 6009, Australia.
authors: Richard J N
authors: RJ
authors: Allcock
authors: Rural Clinical School, School of Medicine, The University of Queensland, Toowoomba, 4350, Australia.
authors: Marcella M S
authors: MM
authors: Kwan
authors: Australian Infectious Diseases Research Centre, The University of Queensland, St. Lucia, Queensland, 4072, Australia.
authors: Helle
authors: H
authors: Bielefeldt-Ohmann
mesh_terms: D000328:Adult; D058491:Bacterial Load; D041963:Bacteroidetes / Q000302:isolation & purification*; D001483:Base Sequence; D016844:Blastocystis / Q000302:isolation & purification*; D016776:Blastocystis Infections / Q000382:microbiology*; D005243:Feces / Q000382:microbiology; D005260:Female; D000068536:Bacillota / Q000302:isolation & purification*; D006801:Humans; D043183:Irritable Bowel Syndrome / Q000382:microbiology*; D008297:Male; D064307:Microbiota / Q000235:genetics*; D008875:Middle Aged; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA
chemical_list: D012336:RNA, Ribosomal, 16S
keywords: Blastocystis; Faecal microbiota; Irritable bowel syndrome