A meta‐analysis on small intestinal bacterial overgrowth in patients with different subtypes of irritable bowel syndrome

Abstract

Background Enteric microbiota is increasingly being recognized as an important factor in the pathogenesis of irritable bowel syndrome (IBS). The reported prevalence of small intestinal bacterial overgrowth (SIBO) in subjects with IBS is highly variable, and there is no consensus on the role of SIBO in different subtypes of IBS, and indications and methods of testing. Methods A comprehensive literature search was performed for studies applying tests for SIBO in subjects with IBS. After applying prospectively decided exclusion criteria, the eligible papers were examined using a meta‐analysis approach for the prevalence of SIBO in subjects with IBS using different tests. The odds ratios of SIBO among subjects with IBS as compared with healthy controls using different tests were calculated. Results Of the available studies (22, 17, 5, and 3 using lactulose and glucose hydrogen breath tests [LHBT and GHBT], jejunal aspirate culture, and more than one tests, respectively) meeting the inclusion criteria, 36.7% (95% confidence interval [CI] 24.2–44.6) had a positive test for SIBO. Patients with IBS were 2.6 (95% CI 1.3–6.9) and 8.3 (95% CI 3.0–5.9) times more likely to have a positive test for SIBO as compared with healthy controls using GHBT and jejunal aspirate culture, respectively. Patients with diarrhea‐predominant IBS were more likely to have positive GHBT as compared with the other subtypes. Conclusions Patients with IBS were more likely to have SIBO as compared with healthy subjects using GHBT and jejunal aspirate culture but not using LHBT. Patients with diarrhea‐predominant IBS more often have SIBO.

Marshall and Warren Lecture 2019: A paradigm shift in pathophysiological basis of irritable bowel syndrome and its implication on treatment

“…Most studies found an association between SIBO diagnosed by quantitative upper gut aspirate culture, glucose and lactulose HBTs and IBS 26 . In a recent meta‐analysis, we found that the relative risk of SIBO among patients with IBS versus control using glucose HBT was 4.234 (95% confidence interval 3.015–5.947), and it was greater among patients with IBS‐D than other subtypes of IBS 26 …”

Faecal Microbiome Transplantation as a Solution to Chronic Enteropathies in Dogs: A Case Study of Beneficial Microbial Evolution

“…Chronic enteropathies (CE) are a frequent and frustrating cause of illness in dogs [ 1 ], defined as persistence of gastrointestinal symptoms such as vomiting and diarrhoea for three or more weeks. In humans and in dogs, both chronic and acute enteropathies exhibit imbalanced composition of intestinal microbiota, defined as dysbiosis, which has been recognized as a major player in the development of these diseases [ 2 , 3 , 4 , 5 , 6 ]. Moreover, as previously reported, CE are characterized by decreased faecal bacterial diversity and richness [ 7 ] with possible impact on the primary functions of gut microbiota.…”

Gut microbiota dysbiosis in functional gastrointestinal disorders: Underpinning the symptoms and pathophysiology

“…Several studies found a strong association between the IBS and SIBO. A meta‐analysis showed a higher relative risk of the SIBO among IBS patients compared with controls 25 . A recent study on patients presenting with bloating, abdominal pain, or diarrhea, thought to be suffering from SIBO, found alterations in small intestinal microbial composition 26 .…”

“…A meta‐analysis showed a higher relative risk of the SIBO among IBS patients compared with controls. 25 A recent study on patients presenting with bloating, abdominal pain, or diarrhea, thought to be suffering from SIBO, found alterations in small intestinal microbial composition. 26 Another study showed a significant reduction of the anaerobic genera Veillonella , Prevotella , and Actinomyces in the duodenal mucosal biopsies from patients with FD compared with healthy controls.…”