Presence of commensal house dust mite allergen in human gastrointestinal tract: a potential contributor to intestinal barrier dysfunction.

Background: Abnormal gut barrier function is the basis of gut inflammatory disease. It is known that house dust mite (HDM) aero-allergens induce inflammation in respiratory mucosa. We have recently reported allergen from Dermatophagoides pteronyssinus (Der p1) to be present in rodent gut.

Perception of lactose intolerance in irritable bowel syndrome patients.

Introduction: The importance of lactose malabsorption in irritable bowel syndrome (IBS) is not well defined and these patients often complain of lactose intolerance. To objectively measure lactose malabsorption, a hydrogen breath test (HBT) can be performed, but a discrepancy emerges between the results of the HBT and the symptomatic response during the HBT.

Aims: To determine in a group of IBS patients whether self-perceived lactose intolerance and the symptomatic response to lactose HBT were conditioned by other factors besides the presence of lactose malabsorption.

Functional bowel symptoms in quiescent inflammatory bowel diseases: role of epithelial barrier disruption and low-grade inflammation.

Objective: To determine the role of colonic barrier defects and low-grade inflammation in irritable bowel syndrome (IBS)-like symptoms in quiescent inflammatory bowel disease (IBD).

Design: Caecal biopsies were collected from 51 IBS, 49 quiescent IBD (31 Crohn's disease (CD) and 18 ulcerative colitis (UC)) patients and 27 controls. IBS was assessed using the Rome III criteria and the IBS severity score.

Role of serological markers of activated eosinophils in inflammatory bowel diseases.

Background: Activated eosinophils can infiltrate the intestinal mucosa in patients with inflammatory bowel disease (IBD), and eosinophils are also implicated in the histological damage seen in allergic diseases.

Aim: To assess, in a group of patients with IBD in remission or with a mild disease activity, whether serological markers of eosinophil activation, eosinophil cationic protein (ECP) and eosinophil protein X (EPX), are related to evidence of IgE hypersensitivity and to the eosinophilia in gut mucosa.

Methods: Sixty-one patients with IBD (21 Crohn's disease and 40 ulcerative colitis) in remission or with a mild disease activity were screened for IgE hypersensitivity and serological levels of ECP and EPX.

Combination of allergic factors can worsen diarrheic irritable bowel syndrome: role of barrier defects and mast cells.

Objectives: Recent evidence suggests a role for increased colonic permeability and mucosal mast cell (MC) mediators on symptoms related to the irritable bowel syndrome (IBS). Whether allergic factors (AFs) are involved in the pathophysiology of IBS is unclear. We addressed the question of the possible influence of an allergic background on IBS symptoms.