[Intestinal permeability disorders in children].

The intestinal mucosa has a certain degree of "porosity", which allows some molecules and macromolecules that are not subject to active transport, to cross the intestinal wall and enter the blood circulation. This permeability of the intestinal mucosa, which depends mostly on the size of the molecule and the state of the mucosa, can be studied with the assistance of protein macromolecules in an allergy-immunological investigation, or with inert markers, so permitting evaluation of the state of integrity of the small intestine. The markers used are polyethylene glycols (PEG) of various molecular weights, Cr EDTA, the monosaccharide sugars mannitol or rhamnose and the disaccharide sugars lactulose or cellobiose. Study of the intestinal permeability to inert markers allows detection of coeliac or Crohn's disease. It can be repeated, especially at the time of food provocation tests needed in the diagnosis of food intolerances in pediatrics in the enteropathology to cows milk proteins, atopic dermatitis and irritable colon in children.