Effect of Food Allergens on the Duodenal Mucosa Visualized by Probe-Based Confocal Laser Endomicroscopy

Abstract

Background : Irritable bowel syndrome (IBS) is a chronic condition affecting around 4% of the global population. Despite extensive testing, only half of IBS patients with suspected food allergies receive a definitive diagnosis using current standard tests. Confocal laser endomicroscopy (CLE) provides high-resolution, real-time visualization of the intestinal mucosa and may offer new insights into the relationship between food allergens and IBS. Methods : This prospective study evaluated the efficacy of the Food Allergen Sensitivity Test (FAST) using CLE to detect immediate structural and functional changes in the duodenal mucosa of IBS patients following exposure to specific food allergens. Forty patients with IBS, as defined by the ROME IV classification, were recruited. The patients underwent standard upper endoscopy followed by the FAST test using the six most popular food allergens. Participants’ IBS symptoms were assessed using the Irritable Bowel Syndrome Severity Scoring System (IBS-SSS) questionnaire at baseline, two months, and six months after the test. Results : Of the 40 patients recruited, 38 completed the study, and 25 showed a positive reaction to food allergens during the FAST test. Following an allergen-specific exclusion diet for six months, participants experienced significant reductions in IBS-SSS scores, and a significant improvement in their daily life with median scores decreasing from 160 at baseline to 35 at two months and 0 at six months (p < 0.05). Discussion : This study highlights the potential of CLE in identifying specific food allergens contributing to IBS symptoms. By using the FAST test to guide personalized exclusion diets, patients reported significant improvements in their symptoms, emphasizing the importance of targeted dietary interventions in IBS management. Meanwhile, traditional endoscopy does not allow for the simultaneous treatment of polyps and diverticula, nor the diagnosis of Crohn’s disease or ulcerative colitis. Conclusion : The FAST test using CLE is a valuable diagnostic tool for identifying food allergens in IBS patients. Personalized dietary interventions based on FAST test results can lead to significant improvements in clinical outcomes, 65.8% of patients responded positively to the procedure reducing the burden of this chronic condition.