Small Intestinal Transit Time Is Delayed in Small Intestinal Bacterial Overgrowth

Area of Science:

• Gastroenterology
• Digestive Health
• Microbiome Research

Background:

• Altered small intestinal motility is a suspected cause of small intestinal bacterial overgrowth (SIBO).
• SIBO symptoms like bloating and weight loss are nonspecific, often delaying diagnosis.
• Limited studies link impaired motility to SIBO due to diagnostic challenges.

Purpose of the Study:

• To determine the relationship between prolonged small bowel transit time (SBTT) measured by wireless motility capsule (WMC) and SIBO, diagnosed by lactulose breath testing (LBT).
• To assess if other motility parameters (gastric, colonic, whole gut transit times) correlate with SIBO.
• To evaluate the association of specific small bowel motility metrics with LBT results.

Main Methods:

• Retrospective analysis of 72 patients undergoing WMC and LBT between April 2009 and December 2012.
• 34 patients with complete data were analyzed for gastric, small bowel, colonic, and whole gut transit times.
• Statistical methods included ANOVA, t-tests, Kruskal Wallis, Wilcoxon rank-sum, and Fisher exact tests.

Main Results:

• 65% of patients (24/37) tested positive for SIBO via LBT.
• Patients with SIBO had a significantly longer mean SBTT (6.6 hours) compared to those without (4.2 hours, P=0.04).
• Prolonged SBTT (≥6 hours) was more common in LBT-positive patients (47.6%) than LBT-negative patients (7.7%, P=0.01).
• SIBO patients also showed prolonged colonic and whole gut transit times, but not delayed gastric emptying.

Conclusions:

• Patients with SIBO exhibit significantly delayed SBTT compared to those without.
• The correlation between prolonged SBTT and positive LBT aids in identifying SIBO and may inform treatment strategies.
• The findings suggest that small bowel transit delay, rather than generalized gastrointestinal dysmotility, specifically predisposes to SIBO.