Abdominal SurgeryMIDESINNCT07416760
Analysis of the Composition of the Intestinal Microbiota in Patients Post-intestinal Anastomosis
An observational study of Abdominal Surgery, run by Instituto de Investigación Sanitaria de la Fundación Jiménez Díaz at 1 site in Spain.
Trial summary
Recent research suggests a significant link between gut microbiota and anastomotic leakage (AL) in colorectal surgery. Patients who develop AL have a higher abundance of bacteria from the Lachnospiraceae family and lower microbial diversity. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Abdominal Surgery
- What is being tested?
- Not applicable- observational study
- How many people
- 30 participants
- Where
- 1 siteSpain
- Study dates
- 14 Feb 2026to 14 Dec 2026
- Phase
- Observational
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Study population: Patients will be selected by the clinical members of the research team from within the population in our setting who will undergo abdominal surgery involving colorectal intestinal anastomosis. To identify patients, the Surgery Department will analyze those who meet the inclusion and exclusion criteria designed for this project during the daily morning clinical session, and patients will then be offered the opportunity to accept/decline participation.
Who may be able to join
- Patients who have undergone colorectal intestinal anastomosis.
- Signing of the informed consent form.
- Age ≥18 years with good functional status.
- Availability for postoperative follow-up.
Who cannot join
- Emergency surgery.
- Intra-abdominal sepsis or previous dehiscence.
- Severe immunosuppression.
- Use of antibiotics in the 3 months prior to preoperative preparation.
- Pregnancy or breastfeeding.
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
Spain1 site, 1 recruiting
- Recruiting
University Hospital Fundación Jiménez Díaz
Madrid, 28040
Héctor Guadalajara-Labajo, MD, PhD, +34 915504800 ext. 4331, h.guadalajara@quironsalud.es
Mariano García-Arranz, PhD, +34 91 5504800 ext. 3398, mariano.garcia@iis-fjd.es
About this study
Official title: Analysis of the Composition of the Intestinal Microbiota and Its Evolution in Patients Post-intestinal Anastomosis
Recent research suggests a significant link between gut microbiota and anastomotic leakage (AL) in colorectal surgery. Patients who develop AL have a higher abundance of bacteria from the Lachnospiraceae family and lower microbial diversity.
Considering the bibliographic data, our main interest is to analyze the microbial population of patients in our social environment and then look for differences in the microbiome between those who have suffered an anastomotic dehiscence (around 8-9% according to the results of our hospital's Surgery Department) and those who have not.
Read the detailed description
The study is designed as a prospective, descriptive, non-interventional research project in which some variables will be analyzed transversally. Patients will be selected by the clinical members of the research team from within the population in our setting who will undergo abdominal surgery involving colorectal intestinal anastomosis. Once accepted, stool samples will be requested prior to surgical preparation, during surgery, and afterwards to determine their microbiome; in this way, we will attempt to correlate the evolution of their anastomosis with their intestinal bacterial population.
- Conditions
- Abdominal Surgery
- Being tested
- Not applicable- observational study
- Keywords
- Microbiome, intestinal anastomosis, dehiscence
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Not applicable- observational studyOther
Fecal sample collection
| Study group | Role | What they receive |
|---|---|---|
| Patients undergoing abdominal surgery with intestinal anastomosis | Older than 18 years of age Receives: Other: Not applicable- observational study |
What is being measured
The primary outcome is the main question the study is designed to answer.
Understand the patient's microbiome
To understand the microbiome of patients undergoing colorectal surgery and the effect of current surgical preparation on the microbiota in our local population.
Measured: From enrollment to a month post surgery
Secondary outcomes (1)
Predictive indicators of colorectal anastomosis postsurgery
Predictive indicators of postoperative outcomes in patients undergoing colorectal anastomosis surgery through metagenomic characterization of the gut microbiota.
Measured: From surgery to a month
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted18 Feb 2026
- Study start14 Feb 2026
- Primary completion14 Feb 2026
- Study completion14 Dec 2026 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (9)Papers the sponsor has linked to this study.
- Other trials for Abdominal SurgeryStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Observational
- Observational model
- Cohort
- Time perspective
- Prospective
- Enrolment
- 30 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Instituto de Investigación Sanitaria de la Fundación Jiménez Díaz
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Mariano Garcia Arranz, Instituto de Investigación Sanitaria de la Fundación Jiménez Díaz
- Investigators
- Mariano García-Arranz, PhD, Principal investigator, Health Research Institute Fundación Jiménez Díaz
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07416760
- Sponsor's protocol ID
- PIC165-25_FJD
- Other IDs
- PIC165-25_FJD
- Acronym
- MIDESIN
- Status last verified
- Feb 2026
- First submitted
- 4 Dec 2025
- Last updated
- 18 Feb 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Yes: Publication of results in open access. Presentation at national surgery conferences.
Publications
Jorgensen AB, Almer L, Brandstrup B, Friis-Hansen L. Fecal microbiomes from screening sampling tubes are stable despite varying sampling and storage conditions. Sci Rep. 2025 Jul 24;15(1):26951. doi: 10.1038/s41598-025-12506-5.
PubMed 40707563Hajjar R, Richard C, Santos MM. The gut barrier as a gatekeeper in colorectal cancer treatment. Oncotarget. 2024 Aug 14;15:562-572. doi: 10.18632/oncotarget.28634.
PubMed 39145528Lianos GD, Frountzas M, Kyrochristou ID, Sakarellos P, Tatsis V, Kyrochristou GD, Bali CD, Gazouli M, Mitsis M, Schizas D. What Is the Role of the Gut Microbiota in Anastomotic Leakage After Colorectal Resection? A Scoping Review of Clinical and Experimental Studies. J Clin Med. 2024 Nov 5;13(22):6634. doi: 10.3390/jcm13226634.
PubMed 39597778Hoedt EC, Carroll GM, Stephensen BD, Morrison M, Vishnoi V, Cuskelly A, Draganic BD, McManus B, Clarke L, Shah KH, Smith SR, Talley NJ, Keely S, Pockney P. Preoperative Antibiotics and Mechanical Bowel Preparation Impact the Colonic Mucosa-Associated Microbiota but Not Anastomotic Leak Rate After Colorectal Resection. Dis Colon Rectum. 2025 Jul 1;68(7):875-886. doi: 10.1097/DCR.0000000000003775. Epub 2025 Apr 11.
PubMed 40214103Xiong Z, Liu J, Chen L, Yang Y, Zhao S. Precision leak detection in the golden window: emerging biomarker strategies for anastomotic integrity monitoring after low anterior resection. Int J Surg. 2025 Oct 1;111(10):7125-7134. doi: 10.1097/JS9.0000000000002891. Epub 2025 Jun 25.
PubMed 40561163Ma K, Gu T, Wu Z, Li Z. Mechanisms of anastomotic leakage in colorectal cancer surgery: unraveling the roles of inflammation, immunity, and microbiota - a narrative review. Int J Surg. 2025 Dec 1;111(12):9482-9495. doi: 10.1097/JS9.0000000000003151. Epub 2025 Aug 6.
PubMed 40773274Barat B, Shogan BD. The Microbiome's Role in Driving Anastomotic Leak and Cancer Recurrence Following Colorectal Surgery. Surg Clin North Am. 2025 Oct;105(5):953-964. doi: 10.1016/j.suc.2025.06.003. Epub 2025 Jul 28.
PubMed 41077437van Praagh JB, de Goffau MC, Bakker IS, Harmsen HJ, Olinga P, Havenga K. Intestinal microbiota and anastomotic leakage of stapled colorectal anastomoses: a pilot study. Surg Endosc. 2016 Jun;30(6):2259-65. doi: 10.1007/s00464-015-4508-z. Epub 2015 Sep 18.
PubMed 26385781Yan J, Wang Q, Li Q, Lu J, Tong Q. Differences in gut microbiota among patients with anastomotic leak following colorectal cancer surgery. Front Microbiol. 2025 Oct 6;16:1578990. doi: 10.3389/fmicb.2025.1578990. eCollection 2025.
PubMed 41122462
Study at a glance
From the registry record, last updated by the sponsor on 18 Feb 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Analysis of the Composition of the Intestinal Microbiota and Its Evolution in Patients Post-intestinal Anastomosis
- ClinicalTrials.gov ID
- NCT07416760
- Acronym / sponsor ID
- MIDESIN / PIC165-25_FJD
- Conditions
- Abdominal Surgery
- Keywords
- Microbiome, intestinal anastomosis, dehiscence
- Study type
- Observational
- Recruitment status
- Recruiting
- Enrolment
- 30 participants (estimated)
- Lead sponsor
- Instituto de Investigación Sanitaria de la Fundación Jiménez DíazUniversity, hospital or other
- Study start
- 14 Feb 2026 (actual)
- Primary completion
- 14 Feb 2026 (actual)
- Study completion
- 14 Dec 2026 (estimated)
- First posted
- 18 Feb 2026 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Recent research suggests a significant link between gut microbiota and anastomotic leakage (AL) in colorectal surgery. Patients who develop AL have a higher abundance of bacteria from the Lachnospiraceae family and lower microbial diversity.
Considering the bibliographic data, our main interest is to analyze the microbial population of patients in our social environment and then look for differences in the microbiome between those who have suffered an anastomotic dehiscence (around 8-9% according to the results of our hospital's Surgery Department) and those who have not.
Detailed description
The study is designed as a prospective, descriptive, non-interventional research project in which some variables will be analyzed transversally. Patients will be selected by the clinical members of the research team from within the population in our setting who will undergo abdominal surgery involving colorectal intestinal anastomosis. Once accepted, stool samples will be requested prior to surgical preparation, during surgery, and afterwards to determine their microbiome; in this way, we will attempt to correlate the evolution of their anastomosis with their intestinal bacterial population.
Study design
- Observational model
- Cohort
- Time perspective
- Prospective
- Number of arms
- 1
| Arm | Type | Receives |
|---|---|---|
| Patients undergoing abdominal surgery with intestinal anastomosis | – | Other: Not applicable- observational studyOlder than 18 years of age |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
- Study population
- Patients will be selected by the clinical members of the research team from within the population in our setting who will undergo abdominal surgery involving colorectal intestinal anastomosis. To identify patients, the Surgery Department will analyze those who meet the inclusion and exclusion criteria designed for this project during the daily morning clinical session, and patients will then be offered the opportunity to accept/decline participation.
Key inclusion criteria (4 listed)
- Patients who have undergone colorectal intestinal anastomosis.
- Signing of the informed consent form.
- Age ≥18 years with good functional status.
- Availability for postoperative follow-up.
Key exclusion criteria (5 listed)
- Emergency surgery.
- Intra-abdominal sepsis or previous dehiscence.
- Severe immunosuppression.
- Use of antibiotics in the 3 months prior to preoperative preparation.
- Pregnancy or breastfeeding.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Not applicable- observational studyFecal sample collection | Other | Patients undergoing abdominal surgery with intestinal anastomosis |
Primary outcome
Understand the patient's microbiome
Time frame: From enrollment to a month post surgery
To understand the microbiome of patients undergoing colorectal surgery and the effect of current surgical preparation on the microbiota in our local population.
1 secondary outcome
Predictive indicators of colorectal anastomosis postsurgery
Time frame: From surgery to a month
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 18 Feb 2026.
- Background: PubMed 40707563Jorgensen AB, Almer L, Brandstrup B, Friis-Hansen L. Fecal microbiomes from screening sampling tubes are stable despite varying sampling and storage conditions. Sci Rep. 2025 Jul 24;15(1):26951. doi: 10.1038/s41598-025-12506-5.
- Background: PubMed 39145528Hajjar R, Richard C, Santos MM. The gut barrier as a gatekeeper in colorectal cancer treatment. Oncotarget. 2024 Aug 14;15:562-572. doi: 10.18632/oncotarget.28634.
- Background: PubMed 39597778Lianos GD, Frountzas M, Kyrochristou ID, Sakarellos P, Tatsis V, Kyrochristou GD, Bali CD, Gazouli M, Mitsis M, Schizas D. What Is the Role of the Gut Microbiota in Anastomotic Leakage After Colorectal Resection? A Scoping Review of Clinical and Experimental Studies. J Clin Med. 2024 Nov 5;13(22):6634. doi: 10.3390/jcm13226634.
- Background: PubMed 40214103Hoedt EC, Carroll GM, Stephensen BD, Morrison M, Vishnoi V, Cuskelly A, Draganic BD, McManus B, Clarke L, Shah KH, Smith SR, Talley NJ, Keely S, Pockney P. Preoperative Antibiotics and Mechanical Bowel Preparation Impact the Colonic Mucosa-Associated Microbiota but Not Anastomotic Leak Rate After Colorectal Resection. Dis Colon Rectum. 2025 Jul 1;68(7):875-886. doi: 10.1097/DCR.0000000000003775. Epub 2025 Apr 11.
- Background: PubMed 40561163Xiong Z, Liu J, Chen L, Yang Y, Zhao S. Precision leak detection in the golden window: emerging biomarker strategies for anastomotic integrity monitoring after low anterior resection. Int J Surg. 2025 Oct 1;111(10):7125-7134. doi: 10.1097/JS9.0000000000002891. Epub 2025 Jun 25.
- Background: PubMed 40773274Ma K, Gu T, Wu Z, Li Z. Mechanisms of anastomotic leakage in colorectal cancer surgery: unraveling the roles of inflammation, immunity, and microbiota - a narrative review. Int J Surg. 2025 Dec 1;111(12):9482-9495. doi: 10.1097/JS9.0000000000003151. Epub 2025 Aug 6.
- Background: PubMed 41077437Barat B, Shogan BD. The Microbiome's Role in Driving Anastomotic Leak and Cancer Recurrence Following Colorectal Surgery. Surg Clin North Am. 2025 Oct;105(5):953-964. doi: 10.1016/j.suc.2025.06.003. Epub 2025 Jul 28.
- Background: PubMed 26385781van Praagh JB, de Goffau MC, Bakker IS, Harmsen HJ, Olinga P, Havenga K. Intestinal microbiota and anastomotic leakage of stapled colorectal anastomoses: a pilot study. Surg Endosc. 2016 Jun;30(6):2259-65. doi: 10.1007/s00464-015-4508-z. Epub 2015 Sep 18.
- Background: PubMed 41122462Yan J, Wang Q, Li Q, Lu J, Tong Q. Differences in gut microbiota among patients with anastomotic leak following colorectal cancer surgery. Front Microbiol. 2025 Oct 6;16:1578990. doi: 10.3389/fmicb.2025.1578990. eCollection 2025.
- Individual participant dataSharing planned: Yes. Publication of results in open access. Presentation at national surgery conferences.
Related trials for Abdominal Surgery
Not yet recruitingObservational study
Pilot Study on the Effectiveness and Safety of OPTILENE® SILVER MESH ELASTIC in Prevention of Surgical Site Infection (SSI) and Incisional Hernia (IH)
Abdominal Aortic Aneurysm, Morbid Obesity
Not yet recruiting
Nurse-Led Prehabilitation Before Major Abdominal Cancer Surgery
Colorectal Cancer
RecruitingPhase 1
Study of Preoperative Radiation Therapy in Participants With Resectable Recurrent Abdominal Adrenocortical Carcinoma
Adrenocortical Carcinoma (ACC), Recurrent Adrenocortical Carcinoma (ACC)
Recruiting
Vagal Stimulator to Reduce Nasogastric Tube Use
Nasogastric Tube Intubation
RecruitingPhase 1
Individual Response to Hyperthermic Intraperitoneal Chemotherapy (HIPEC) Treatment of Peritoneal Carcinomatosis From Peritoneal Mesothelioma or Atypical Mesothelial Proliferation or From Ovarian, Colorectal, or Appendiceal Histologies
Peritoneal Mesothelioma, Peritoneal Carcinomatosis
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
Mariano García-Arranz, PhD principal investigator
Health Research Institute Fundación Jiménez Díaz
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
An observational study of Abdominal Surgery, run by Instituto de Investigación Sanitaria de la Fundación Jiménez Díaz at 1 site in Spain.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 4 inclusion and 5 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: looking for participants now, as of the sponsor's last update on 18 Feb 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Spain. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Héctor Guadalajara-Labajo, MD, PhD (+ 34 550 4800 ext. 4331, h.guadalajara@quironsalud.es), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Understand the patient's microbiome (time frame: From enrollment to a month post surgery). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT07416760, which also lists 9 linked publications.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 18 Feb 2026; AzTrials last refreshed its copy on 8 Nov 2026.