PEG bowel preparation effects on gut microbes after gallbladder removal
Clinical Experimental Study on the Impact of PEG Laxatives for Intestinal Preparation on Gut Microbiota in Patients Undergoing Cholecystectomy
This study tests whether PEG-based colonoscopy prep causes larger or longer-lasting changes to gut microbes in adults who have had their gallbladder removed compared with people who still have their gallbladder.
Quick facts
| Study type | Observational |
|---|---|
| Enrollment | 20 (estimated) |
| Ages | 18 Years to 65 Years |
| Sex | All |
| Sponsor | Tongji Hospital Academic / other |
| Locations | 1 site (Wuhan, Hubei) |
| Trial ID | NCT07439640 on ClinicalTrials.gov |
What this trial studies
This prospective, parallel-group observational cohort at Tongji Hospital will enroll about 20 adults, split into roughly 10 with prior cholecystectomy (≥6 months) and 10 age- and sex-matched controls with intact gallbladders. All participants will receive standard PEG-based bowel preparation for colonoscopy and provide stool samples at baseline, at the first non-watery stool after colonoscopy, and at 1, 3, and 6 months post-procedure. Metagenomic shotgun sequencing will be performed to profile taxonomic and functional changes in the microbiome and compare recovery trajectories between groups. Key exclusions include recent antibiotic/probiotic use and major organ disease to reduce confounding factors.
Who should consider this trial
Good fit: Adults aged 18–75 scheduled for colonoscopy with PEG who either had cholecystectomy at least 6 months prior or have an intact gallbladder, and who have not used antibiotics, probiotics, or prebiotics in the previous 6 months are ideal candidates.
Not a fit: People who recently used antibiotics/probiotics, have major organ disease, are pregnant or breastfeeding, cannot tolerate PEG, or cannot comply with stool collection are unlikely to receive benefit from joining this study.
Why it matters
Potential benefit: If successful, the results could help guide colonoscopy preparation and follow-up care to reduce or manage long-term gut microbiota disruptions in people who have had a cholecystectomy.
How similar studies have performed: Animal studies and some human data show that PEG and cholecystectomy can each alter the gut microbiome, but combined effects in humans have not been systematically studied.
Eligibility criteria
Show full inclusion / exclusion criteria
Inclusion Criteria: * Scheduled to undergo colonoscopy with polyethylene glycol (PEG)-based bowel preparation. * For the gallbladder removal group: prior cholecystectomy performed at least 6 months before enrolment. * For the normal group: intact gallbladder (no history of cholecystectomy). * Willing and able to provide written informed consent. * Willing to collect and mail stool samples at five specified time points (baseline, first non-watery stool after colonoscopy, 1 month, 3 months, 6 months). Exclusion Criteria: * Contraindications to colonoscopy (e.g., severe cardiopulmonary insufficiency, acute gastrointestinal bleeding, severe coagulopathy). * Known intolerance or allergy to polyethylene glycol (PEG). * Use of antibiotics, probiotics, or prebiotics within 6 months prior to enrolment. * Pregnancy or breastfeeding. * Mental disorders or any condition that may compromise the ability to comply with study procedures. * Major organ diseases (e.g., liver cirrhosis, chronic kidney disease stage 4-5, uncontrolled diabetes mellitus). * Participation in another interventional clinical trial within the last 3 months.
Where this trial is running
Wuhan, Hubei
- Department of Gastroenterology Tongji Hospital, Tongji Medical college, Huazhong University of Science and technology — Wuhan, Hubei, China (Recruiting)
Study contacts
- Study coordinator: ping h Xie
- Email: hpxie@tjh.tjmu.edu.cn
- Phone: 86+13437187007
How to participate
- Review the eligibility criteria above with your treating physician.
- Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
- Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.