The impact of alcohol consumption and cholecystectomy on small intestinal bacterial overgrowth

Dig Dis Sci. 2014 Mar;59(3):638-44. doi: 10.1007/s10620-013-2960-y. Epub 2013 Dec 10.


Background: The etiology of small intestinal bacterial overgrowth (SIBO) is diverse and frequently multi-factorial. SIBO is thought to result from structural changes of the gastrointestinal tract, disordered peristalsis of the stomach and/or small intestine, or a disruption of the normal mucosal defenses of the small intestine. Alcoholics are reported to have higher rates of SIBO, as diagnosed by jejunal aspirate; however, no data are available on the association between moderate alcohol consumption and SIBO.

Aim: To evaluate the association between moderate alcohol consumption and SIBO and identify risk factors for SIBO using the lactulose breath test (LBT).

Methods: A retrospective chart review was completed for 210 consecutive patients who underwent the LBT between 2008 and 2010. We reviewed demographic data, including age, race, body mass index, alcohol and tobacco history, medication use, comorbid medical conditions, and history of abdominal surgery.

Results: The study included 196 patients (68 % female; mean age 55 years), 93 of whom had a positive LBT (47.4 %). Of those patients who consumed a moderate amount of alcohol, 58 % had a positive LBT, compared to 38.9 % of abstainers (P = 0.008). Those with a history of cholecystectomy had significantly lower rates of a positive LBT than those who had not (33.3 vs. 51.7 % respectively; P = 0.031). Neither proton pump inhibitor (PPI) use nor tobacco use was associated with a positive LBT.

Conclusion: In this retrospective review, moderate alcohol consumption was a strong risk factor for SIBO. Cholecystectomy appeared to be protective against SIBO. Neither PPI use nor tobacco use was associated with an increased risk of SIBO.

Publication types

  • Evaluation Study

MeSH terms

  • Adult
  • Aged
  • Alcohol Drinking / adverse effects*
  • Appendectomy
  • Biomarkers / metabolism
  • Breath Tests
  • Case-Control Studies
  • Cholecystectomy*
  • Female
  • Humans
  • Intestine, Small / microbiology*
  • Lactulose / metabolism
  • Linear Models
  • Logistic Models
  • Malabsorption Syndromes / diagnosis
  • Malabsorption Syndromes / etiology*
  • Malabsorption Syndromes / metabolism
  • Malabsorption Syndromes / prevention & control
  • Male
  • Middle Aged
  • Multivariate Analysis
  • Retrospective Studies
  • Risk Factors


  • Biomarkers
  • Lactulose