Intestinal permeability and screening tests for coeliac disease

Area of Science:

• Gastroenterology
• Clinical Diagnostics
• Molecular Biology

Background:

• Small intestine diseases, such as gluten-sensitive enteropathy, are characterized by increased permeability to large molecules.
• This altered permeability affects the absorption of disaccharides and small polar molecules, impacting nutrient uptake.
• Assessing intestinal permeability is crucial for diagnosing various gastrointestinal disorders.

Purpose of the Study:

• To evaluate a novel oral permeability test utilizing cellobiose and mannitol.
• To determine the test's efficacy in differentiating between healthy individuals and patients with gastrointestinal diseases.
• To assess the test's utility as a screening tool for celiac disease.

Main Methods:

• Simultaneous oral administration of cellobiose (disaccharide) and mannitol (small polar molecule).
• Measurement of the ratio of five-hour urinary recoveries of cellobiose to mannitol.
• Application of the test across various gastrointestinal conditions including celiac disease, Crohn's disease, and others.

Main Results:

• Patients with pancreatic insufficiency, bacterial overgrowth, hypolactasia, and colonic inflammatory bowel disease showed normal permeability ratios.
• Abnormal cellobiose/mannitol ratios were observed in 23 out of 24 untreated celiac patients.
• Five out of eight patients with proximal small bowel Crohn's disease also exhibited abnormal ratios.

Conclusions:

• The cellobiose/mannitol test is a sensitive and accurate method for assessing small intestine permeability.
• This test demonstrates superior performance compared to existing screening methods for celiac disease, with fewer false positives and negatives.
• The novel oral test holds significant potential for diagnosing and screening for various gastrointestinal disorders affecting small intestine integrity.