Prevalence of Gluten Sensitivity in Irritable Bowel Syndrome: The First Study in Paediatrics. (GS-IBS)

Recently a new clinical entity, gluten sensitivity (GS), a form of gluten intolerance in which neither allergic nor autoimmune mechanisms can be identified, has been added to the spectrum of gluten-related disorders. This condition is characterized by gastrointestinal and extra-intestinal symptoms including abdominal pain (68%); eczema or rash (40%); headache (35%); diarrhoea (33%) and fatigue (33%). The small intestine of GS patient is usually normal. The prevalence of GS is not yet established although it is estimated that up to 6% of the general population might be affected. GS has been described only in adults and no data are available for the paediatric population.The main problem with this new condition is that, at present, there are no specific biomarkers to confirm GS diagnosis. In the absence of a serological or histological marker, the diagnosis remains clinical. In order to avoid placebo effect of the dietary treatment, presently GS diagnosis needs to performed with double-blind randomized placebo-controlled challenge provided that both wheat allergy and CD have previously been excluded.

The primary aim of the study is to evaluate the prevalence of GS in IBS paediatric patients.

The secondary aims are: 1) to describe clinical, serologic, genetic and histological profile of GS patient and 2) to study the role of gluten or other possible wheat components in the onset of GS.

Study design Randomized double blind placebo controlled cross over re-challenge trial. Patient consecutively diagnosed as having IBS (Rome III criteria) in whom the diagnosis of coeliac disease and wheat allergy has been excluded, will be considered eligible for the study.

Diagnosis of coeliac disease and wheat allergy will be excluded by the negativity of TTG-IgA and/or EMA and of Skin Prick Test, RAST immuno-CAP and Atopy patch test respectively.

Patients will entered a three-phase study with a running in phase (phase I: weeks 1-2), diagnostic elimination diet phase (phase II: week 3-4) and re-challenge phase (phase III: week 5-12)