Symptomatic Response to Gluten Challenge in Patients With Suspected Non Celiac Gluten Sensitivity
Condition: Non Celiac Gluten Sensitivity
MeSH terms: Hypersensitivity
Study type: Interventional

Summary: 
      Non Celiac Gluten Sensitivity (NCGS) is an emergent syndrome mainly inducing gastrointestinal
      symptoms. NCGS is suspected to be present in the 6% of the population and thus it represents
      an important issue in health care. Actually it remains difficult to diagnose and prove due to
      the lack of established criteria. The investigators intention is to establish a diagnostic
      flowchart to evaluate the real impact of NCGS in a cohort of patients suffering from
      functional gastrointestinal symptoms.
    

Detailed description: 
      The proposed study has been designed to be a randomised double-blind multicenter clinical
      trial with crossover. The Coordinating Center will be the "Centro per la Prevenzione e la
      Diagnosi della Malattia Celiaca", Fondazione IRCCS Ca' Granda - Ospedale Maggiore
      Policlinico, Milano. Secondary enrollment centers will be Italian Gastroenterology Units with
      outpatient services. Enrollment criteria will be diagnosis of irritable bowel syndrome (IBS)
      or functional dyspepsia. Patients with other functional gastrointestinal disorders will be
      included in the group "Functional non specific gastrointestinal symptoms".

      After they give their written informed consent, patients will undergo the diagnostic work-up
      recommended in case of suspected irritable bowel symptoms/functional dyspepsia and aimed at
      the exclusion of CD or allergy to alimentary antigens by means of serological testing (anti
      transglutaminase antibodies) or skin tests, or other gastrointestinal diseases. Endoscopic,
      histologic and/or imaging exams together with supplemental blood tests will be prescribed on
      individual cases and according with the international guidelines.

      Enrolled subjects will be asked to fill

        -  a checklist for the evaluation of the psychological profile (SCL90 questionnaire, with
           the particular aim of evaluating levels of anxiety, depression and somatisation);

        -  a questionnaire about the perceived level of physical and mental health (SF36
           questionnaire);

        -  Ten centimeters long visual analogue scales (VAS) on the level of satisfaction with
           their health status and on the intensity of the single symptoms.

      At the end of the present phase patients will start a GFD for the subsequent three weeks.

      At the end of the GFD period patients will fill VAS and SF36. Only those patients presenting
      a 30% increase of the global VAS score ("GFD Responders") will continue the study.
      Conversely, non responders will be considered "non gluten sensitive" and they will finish the
      trial.

      Responders to the GFD period will entry the randomisation phase and will undergo a
      double-blind stimulation test with cross over. Patients will be randomised to assume gluten
      or placebo for 7 days. After the treatment patients will fill VAS and SF36.

      A diagnosis of NCGS will be ascertained in case of symptomatic response limited to gluten
      ingestion.
    

Intervention name(s): gluten; Placebo
Intervention type(s): Dietary Supplement; Dietary Supplement
Intervention description(s): The enrolled patients will be invited to follow a gluten free diet. Patients responsive to the diet will be invited to assume gluten or placebo following a double blind with cross over scheme; Patients responsive to the diet will be invited to blindly assume gluten or placebo following a double blind with cross over scheme
Allocation: Randomized
Intervention model: Crossover Assignment
Masking: Triple (Participant, Care Provider, Investigator)
Primary purpose: Diagnostic
Keywords: non celiac gluten sensitivity; gluten; irritable bowel syndrome; functional disorders