Small intestinal bacterial overgrowth in patients with irritable bowel syndrome. Issue 6 (5th December 2006)

• Record Type: Journal Article
• Authors: Posserud, Iris; Stotzer, Per-Ove; Björnsson, Einar S; Abrahamsson, Hasse; Simrén, Magnus
• Is Part Of: Gut. Volume 56:Issue 6(2007)
• Page Start: 802
• Page End: 808
• Publication Date: 2006-12-05
• Subjects: GHBT, glucose hydrogen breath test -- IBS, irritable bowel syndrome -- LHBT, lactulose hydrogen breath test -- MMC, migrating motor complex -- SIBO, small intestinal bacterial overgrowth; Gastroenterology -- Periodicals; 616.33
• DOI: 10.1136/gut.2006.108712
• Languages: English
• ISSNs: 0017-5749

Abstract

Abstract : Background: Small intestinal bacterial overgrowth (SIBO) has been proposed to be common in irritable bowel syndrome (IBS), with altered small-bowel motility as a possible predisposing factor. Aim: To assess the prevalence of SIBO, by culture of small-bowel aspirate, and its correlation to symptoms and motility in IBS. Methods: 162 patients with IBS who underwent small-bowel manometry and culture of jejunal aspirate were included. Cultures from 26 healthy subjects served as controls. Two definitions of altered flora were used: the standard definition of SIBO (⩾10 5 colonic bacteria/ml), and mildly increased counts of small-bowel bacteria (⩾95th centile in controls). Results: SIBO (as per standard definition) was found in 4% of both patients and controls. Signs of enteric dysmotility were seen in 86% of patients with SIBO and in 39% of patients without SIBO (p = 0.02). Patients with SIBO had fewer phase III activities (activity fronts) than patients without SIBO (p = 0.08), but otherwise no differences in motility parameters were seen. Mildly increased bacterial counts (⩾5×10 3 /ml) were more common in patients with IBS than in controls (43% vs 12%; p = 0.002), but this was unrelated to small intestinal motility. No correlation between bacterial alterations and symptom pattern was observed. Conclusions: The data do not support an important role for SIBO according to commonly used clinical definitions, in IBS. However, mildly increased counts of small-bowel bacteria seem to be more common in IBS, and needs further investigation. Motility alterations could not reliably predict altered small-bowel bacterial flora.