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Small intestinal bacterial overgrowth

Eamonn M M Quigley1, Ahmed Abu-Shanab

  • 1Alimentary Pharmabiotic Centre, University College Cork, Cork, Ireland. e.quigley@ucc.ie

Infectious Disease Clinics of North America
|October 13, 2010
PubMed

Insights

Small intestinal overgrowth, linked to gut microbiota imbalances, is poorly defined due to diagnostic challenges. Current diagnostic methods lack standardization, impacting treatment effectiveness and prevalence studies.

Area of Science:

  • Gastroenterology
  • Microbiology
  • Internal Medicine

Background:

  • The role of the microbiota in health and disease is gaining interest.
  • Small intestinal bacterial overgrowth (SIBO) has been recognized for over 50 years as a cause of malabsorption.
  • Despite this recognition, SIBO remains poorly defined in clinical practice.

Purpose of the Study:

  • To highlight the lack of consensus in diagnosing small intestinal bacterial overgrowth.
  • To discuss the limitations of current diagnostic methodologies for SIBO.
  • To address the weak evidence base for SIBO treatments.

Main Methods:

  • Review of existing literature on small intestinal bacterial overgrowth diagnosis and treatment.
  • Analysis of the limitations of jejunal aspirate culture and breath tests.
  • Examination of the evidence supporting common antibiotic regimens.

Main Results:

  • There is no gold standard for diagnosing small intestinal bacterial overgrowth.
  • Common diagnostic methods (jejunal aspirate culture, breath tests) show significant variability in performance and interpretation.
  • This variability leads to inconsistent prevalence estimates across different clinical settings.
  • The evidence supporting current treatment protocols, primarily antibiotics, is limited.

Conclusions:

  • Small intestinal bacterial overgrowth diagnosis lacks standardization, hindering clear definition and research.
  • Variability in diagnostic methods impacts the understanding of SIBO prevalence.
  • Treatment strategies for SIBO are not robustly supported by clinical trial evidence.

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