Lactose Intolerance and Intestinal Permability

NCT07424898 | Enrolling By Invitation

• 1 other identifier: E-54022451-050.04-212534
• Study Type: observational
• Target: 200
• Locations: 1 country
• Sites: 1

Brief Summary

"This study evaluates the interplay between lactose intolerance, intestinal barrier function (zonulin), and intestinal inflammation (fecal calprotectin) in adults, aiming to clarify their independent contributions to symptom severity and quality of life."

Conditions

Lactose Intolerance, Adult Type; Intestinal Permability; IBS (Irritable Bowel Syndrome)

Keywords

Zonulin; Lactose tolerance test; Bristol stool scale; Fecal calprotectin; Gastrointestinal symtom rating scale; IBS-symptom severity scale; IgE specific casein

Outcome Measures

Primary Outcomes (1)

• To determine the relationship between lactose intolerance (LI) and fecal biomarkers, zonulin (Z) and fecal calprotectin (FC), in adults with IBS.

  The primary outcome of this study is to evaluate the relationship between lactose intolerance (LI) and fecal biomarkers-Z (as mg/kg), a marker of intestinal permeability (IP), and fecal calprotectin (FC) (as mg/kg), a marker of intestinal inflammation-in adults with irritable bowel syndrome (IBS). This includes assessing whether levels of these biomarkers are associated with the presence of LI and the severity of gastrointestinal symptoms related to lactose ingestion. The analysis aims to clarify how intestinal barrier function (Z) and inflammation (FC) contribute individually and jointly to symptom manifestation in LI patients within the IBS population.

  Baseline assessment (single time point measurement of biomarkers and symptoms)

Secondary Outcomes (1)

• FC predictive value with Z. Z correlation with symptom severity. Z in IBS subtypes / FC and organic pathology. Z mediation between LI and symptoms. IgE anti-casein and symptom severity. LTT correlation with IP biomarkers. Celiac serology prevalence.

  Baseline assessment (single measurement at the time of evaluation)

Study Arms (1)

Patients with Irritable bowel sydrome.

IBS-C, IBS-D and IBS-M.

Eligibility Criteria

• Age: 18 Years - 70 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Probability Sample

Study Population

Patients with IBS, aged 18-70 years, both male and female, who meet the Rome-4 criteria, were included in this study. They were recruited from the Gastroenterology outpatient clinic of Bezmialem Vakıf University Hospital, with a minimum total of 200 patients.

You may qualify if:

• Adults aged 18-70 years; experiencing chronic symptoms (diarrhea, bloating, abdominal pain, constipation, flatulence) for the past 3 months, potentially fitting IBS criteria.

You may not qualify if:

• \- Acute gastroenteritis (\< 4 weeks), Active gastrointestinal bleeding (stomach, small intestine, and colon), Known celiac disease, Bariatric surgery or short bowel syndrome, Pregnancy or lactation, Type I and II Diabetes mellitus, Antibiotic use within the last 2 weeks, High-dose NSAIDs within the last 2 weeks, Initiation of probiotics or prebiotics within the last 4 weeks, High-dose PPI use (optional), Inflammatory bowel disease (IBD; ulceretive colitis and Crohn's colitis) with active severe flare (excluded from primary analyses, evaluated separately in subgroup analyses)

Sponsors & Collaborators

• Bezmialem Vakif University: lead

Study Sites (1)

Bezmialem Vakıf University Medical Faculty Hospital

Istanbul, 34093, Turkey (Türkiye)

Location

Related Publications (8)

• Guingand DE Rivery M, Zeinab H, Cohen V, Baumstarck K, Luciano L, Vitton V. Does fecal calprotectin increase may be linked to lactose intolerance in patients with irritable bowel syndrome? Minerva Gastroenterol (Torino). 2023 Sep;69(3):329-334. doi: 10.23736/S2724-5985.21.02802-6. Epub 2021 Apr 8.

  PMID: 33829725 RESULT

• Jendraszak M, Galecka M, Kotwicka M, Schwiertz A, Regdos A, Pazgrat-Patan M, Andrusiewicz M. Impact of Biometric Patient Data, Probiotic Supplementation, and Selected Gut Microorganisms on Calprotectin, Zonulin, and sIgA Concentrations in the Stool of Adults Aged 18-74 Years. Biomolecules. 2022 Nov 29;12(12):1781. doi: 10.3390/biom12121781.

  PMID: 36551209 RESULT

• Tyszka M, Maciejewska-Markiewicz D, Bilinski J, Lubas A, Stachowska E, Basak GW. Increased Intestinal Permeability and Stool Zonulin, Calprotectin and Beta-Defensin-2 Concentrations in Allogenic Hematopoietic Cell Transplantation Recipients. Int J Mol Sci. 2022 Dec 15;23(24):15962. doi: 10.3390/ijms232415962.

  PMID: 36555600 RESULT

• Czaja-Bulsa G, Bulsa K, Lokiec M, Drozd A. Can Faecal Zonulin and Calprotectin Levels Be Used in the Diagnosis and Follow-Up in Infants with Milk Protein-Induced Allergic Proctocolitis? Nutrients. 2024 Sep 2;16(17):2949. doi: 10.3390/nu16172949.

  PMID: 39275265 RESULT

• Szymanska E, Wierzbicka A, Dadalski M, Kierkus J. Fecal Zonulin as a Noninvasive Biomarker of Intestinal Permeability in Pediatric Patients with Inflammatory Bowel Diseases-Correlation with Disease Activity and Fecal Calprotectin. J Clin Med. 2021 Aug 30;10(17):3905. doi: 10.3390/jcm10173905.

  PMID: 34501351 RESULT

• Schnedl WJ, Michaelis S, Enko D, Mangge H. Fecal Calprotectin Elevations Associated with Food Intolerance/Malabsorption Are Significantly Reduced with Targeted Diets. Nutrients. 2023 Feb 27;15(5):1179. doi: 10.3390/nu15051179.

  PMID: 36904178 RESULT

• Seidita A, Mansueto P, Giuliano A, Chiavetta M, Soresi M, Carroccio A, The Internal Medicine Study Group. Fecal Calprotectin in Self-Reported Milk Intolerance: Not Only Lactose Intolerance. Nutrients. 2023 Feb 20;15(4):1048. doi: 10.3390/nu15041048.

  PMID: 36839406 RESULT

• Fasano A. Zonulin and its regulation of intestinal barrier function: the biological door to inflammation, autoimmunity, and cancer. Physiol Rev. 2011 Jan;91(1):151-75. doi: 10.1152/physrev.00003.2008.

  PMID: 21248165 RESULT

MeSH Terms

Conditions

Lactose Intolerance, Adult Type; Irritable Bowel Syndrome

Condition Hierarchy (Ancestors)

Colonic Diseases, Functional; Colonic Diseases; Intestinal Diseases; Gastrointestinal Diseases; Digestive System Diseases

Study Design

• Study Type: observational
• Observational Model: OTHER
• Time Perspective: CROSS SECTIONAL
• Target Duration: 12 Weeks
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: February 16, 2026
• First Posted: February 20, 2026
• Study Start: February 10, 2026
• Primary Completion (Estimated): December 15, 2026
• Study Completion (Estimated): June 15, 2027
• Last Updated: February 25, 2026

Record last verified: 2026-02

Data Sharing

• IPD Sharing: Will not share

Locations

TU (1)