Allergic food hypersensitivity in irritable bowel syndrome

The role of immuno-allergic reactions to food in patients with irritable bowel syndrome (IBS) remains controversial because of non-specific symptoms and of diagnostic methods limited by difficult accessibility to the gut. In clinical practice, the manifestations of food hypersensitivity in the gastro-intestinal tract are difficult to assess and to differentiate from digestive symptoms due to other causes. Pathophysiological hypotheses based on immunological mechanisms of immediate hypersensitivity (IgE and non IgE) and of delayed hypersensitivity, including mast cells and eosinophils, have been proposed. Recent pathophysiological concepts concerning IBS suggest the existence of alterations in the integrity of the intestinal epithelial barrier that would promote increased presentation of luminal antigens, with the development and maintenance of "low grade" mucosal inflammation with involvement of the enteric nervous system, potentially being the origin of these sensitive motility disorders and the abdominal pain. The diagnostic tests used in clinical practice (skin tests and specific IgE serum) to identify the source of self-perceived reactions to food reported by patients are often negative, as are oral provocation tests. Classic manifestations of atopy (rhinitis, dermatitis, asthma) seem to be the background favoring IBS, at least in the subgroup of patients reporting clinical symptoms after ingestion of certain foods. (C) 2014 Elsevier Masson SAS. All rights reserved.