title: Small intestinal bacterial overgrowth is associated with irritable bowel syndrome and is independent of proton pump inhibitor usage.
abstract: BACKGROUND
  Current knowledge suggests that small intestinal overgrowth participates in the pathogenesis of irritable bowel syndrome. It is questionable if this association is modulated by intake of proton pump inhibitors (PPIs).
  
  
  METHODS
  In a prospective study, quantitative cultures of duodenal aspirates were performed for aerobic species in 897 consecutive patients undergoing upper GI tract endoscopy. SIBO was defined as equal to or more than 10(3) cfu/ml. The effect of PPI intake on the relationship between SIBO and IBS was the primary endpoint.
  
  
  RESULTS
  Analysis among patients without any history of PPI intake (n = 713) showed that odds ratio (OR) for IBS in the event of SIBO was 5.63 (3.73-8.51, p < 0.0001); this was 4.16 (1.91-9.06) when analysis was done among patients with history of PPI intake (n = 184, p: 0.498 between patients without and with PPI intake). Multiple logistic regression analysis found that factors independently associated with SIBO were age above or equal to 60 years (OR: 2.36), body mass index more than or equal to 22 kg/m(2) (OR: 0.60), presence of IBS (OR: 6.29), type 2 diabetes mellitus (OR: 1.59) and gastritis (OR: 0.47).
  
  
  CONCLUSIONS
  The association between IBS and SIBO was completely independent from PPI intake. Although gastritis was protective against SIBO, results show that PPI intake cannot prime SIBO.
authors.affiliation: 4th Department of Internal Medicine, National and Kapodistrian University of Athens, Medical School, Athens, Greece. egiamarel@med.uoa.gr.
authors.forename: Evangelos J
authors.initials: EJ
authors.lastname: Giamarellos-Bourboulis
authors.affiliation: Department of Gastroenterology, Sismanogleion Athens General Hospital, Marousi, Greece.
authors.forename: Emmanouel
authors.initials: E
authors.lastname: Pyleris
authors.affiliation: Department of Gastroenterology, Sismanogleion Athens General Hospital, Marousi, Greece.
authors.forename: Charalambos
authors.initials: C
authors.lastname: Barbatzas
authors.affiliation: 4th Department of Internal Medicine, National and Kapodistrian University of Athens, Medical School, Athens, Greece.
authors.forename: Aikaterini
authors.initials: A
authors.lastname: Pistiki
authors.affiliation: GI Motility Program, Cedars-Sinai Medical Center, Los Angeles, CA, USA.
authors.forename: Mark
authors.initials: M
authors.lastname: Pimentel
mesh_terms: D000368:Aged; D001765:Blind Loop Syndrome / Q000150:complications*; D004386:Duodenum / Q000382:microbiology*; D006801:Humans; D043183:Irritable Bowel Syndrome / Q000150:complications* / Q000382:microbiology*; D008875:Middle Aged; D011446:Prospective Studies; D054328:Proton Pump Inhibitors / Q000627:therapeutic use*
chemical_list: D054328:Proton Pump Inhibitors
keywords: Irritable bowel syndrome; Proton pump inhibitors; Small intestinal overgrowth