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Perturbations of Circulating miRNAs in Irritable Bowel Syndrome Detected Using a Multiplexed High-throughput Gene Expression Platform
Published on: November 30, 2016
Bacterial concepts in irritable bowel syndrome
1Division of Gastrointestinal and Liver Diseases, Keck School of Medicine, University of Southern California, Los Angeles, California, USA.
Reviews in Gastroenterological Disorders
|August 24, 2007
Summary
Excessive intestinal gas in irritable bowel syndrome (IBS) may stem from small intestinal bacterial overgrowth (SIBO). Treating SIBO with antibiotics significantly improved IBS symptoms in a study, suggesting a new therapeutic approach.
Area of Science:
- Gastroenterology
- Microbiology
- Immunology
Background:
- Irritable bowel syndrome (IBS) presents with overlapping symptoms across subtypes, including gas, bloating, pain, and altered bowel habits.
- Excessive intestinal gas, a byproduct of microbial fermentation, may unify IBS symptoms.
- Abnormal gut microbial distribution, specifically small intestinal bacterial overgrowth (SIBO), is implicated in IBS pathogenesis.
Purpose of the Study:
- To investigate the role of small intestinal bacterial overgrowth (SIBO) in the pathophysiology of irritable bowel syndrome (IBS).
- To evaluate the efficacy of antibiotic therapy in treating SIBO and associated IBS symptoms.
Main Methods:
- Lactulose breath testing to detect SIBO and identify methane producers, associated with constipation-predominant IBS.
- Double-blind, placebo-controlled study assessing antibiotic treatment for SIBO in IBS patients.
- Use of prokinetic agents post-antibiotic therapy to prevent SIBO relapse by stimulating gut motility.
Main Results:
- Antibiotic treatment successfully eradicated bacterial overgrowth in IBS patients.
- A significant 75% improvement in IBS symptoms was observed following successful SIBO treatment.
- Normalization of lactulose breath tests correlated with clinical improvement.
Conclusions:
- Small intestinal bacterial overgrowth (SIBO) is a potential underlying cause of irritable bowel syndrome (IBS).
- Antibiotic therapy targeting SIBO offers a promising treatment strategy for IBS, leading to substantial symptom relief.
- Prokinetic agents may play a role in long-term management by preventing SIBO recurrence.
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