title: Randomised clinical study: gluten challenge induces symptom recurrence in only a minority of patients who meet clinical criteria for non-coeliac gluten sensitivity.
abstract: BACKGROUND
  It is unknown whether symptoms in non-coeliac patients (non-CD) meeting clinical diagnostic criteria for noncoeliac gluten sensitivity (NCGS) are specifically triggered by gluten.
  
  
  OBJECTIVE
  To assess gluten sensitivity in patients diagnosed with NCGS.
  
  
  METHODS
  We studied 35 non-CD subjects (31 females) that were on a gluten-free diet (GFD), in a double-blind challenge study. Participants were randomised to receive either gluten-containing flour or gluten-free flour for 10 days, followed by a 2-week washout period and were then crossed over. The main outcome measure was their ability to identify which flour contained gluten. Secondary outcome measures were based upon Gastrointestinal Symptoms Rating Scale (GSRS) scores.
  
  
  RESULTS
  The gluten-containing flour was correctly identified by 12 participants (34%), who were classified as having NCGS. Their mean GSRS dimension scores were significantly higher following gluten challenge compared to baseline. The scores were: pain, 1.7 ± 0.8 vs. 2.6 ± 1.0; reflux, 1.6 ± 0.5 vs. 2.2 ± 0.9; indigestion, 1.9 ± 0.7 vs. 3.2 ± 1.1; diarrhoea, 1.6 ± 0.7 vs. 2.9 ± 1.5 and constipation, 1.9 ± 0.9 vs. 2.9 ± 1.3. Seventeen participants (49%) erroneously considered the gluten-free flour to contain gluten. Their mean GSRS dimension scores were significantly higher following gluten-free flour challenge compared to baseline. The scores were: pain, 1.6 ± 0.9 vs. 3.0 ± 0.9; reflux, 1.4 ± 0.5 vs. 2.3 ± 1.1; indigestion, 2.0 ± 1.1 vs. 3.7 ± 1.1; diarrhoea, 1.6 ± 0.7 vs. 3.0 ± 1.2 and constipation, 1.6 ± 0.9 vs. 2.6 ± 1.3. The other six participants (17%) were unable to distinguish between the flours.
  
  
  CONCLUSIONS
  Double-blind gluten challenge induces symptom recurrence in just one-third of patients fulfilling the clinical diagnostic criteria for non-coeliac gluten sensitivity.
authors: Department of Gastroenterology, University and Spedali Civili of Brescia, Brescia, Italy.
authors: B
authors: B
authors: Zanini
authors: Department of Gastroenterology, University and Spedali Civili of Brescia, Brescia, Italy.
authors: R
authors: R
authors: Baschè
authors: Department of Gastroenterology, University and Spedali Civili of Brescia, Brescia, Italy.
authors: A
authors: A
authors: Ferraresi
authors: Department of Gastroenterology, University and Spedali Civili of Brescia, Brescia, Italy.
authors: C
authors: C
authors: Ricci
authors: Department of Gastroenterology, University and Spedali Civili of Brescia, Brescia, Italy.
authors: F
authors: F
authors: Lanzarotto
authors: Department of Gastroenterology, University and Spedali Civili of Brescia, Brescia, Italy.
authors: M
authors: M
authors: Marullo
authors: Department of Pathology, University and Spedali Civili of Brescia, Brescia, Italy.
authors: V
authors: V
authors: Villanacci
authors: Department of Food, Environmental and Nutritional Sciences, University of Milan, Milan, Italy.
authors: A
authors: A
authors: Hidalgo
authors: Department of Gastroenterology, University and Spedali Civili of Brescia, Brescia, Italy.
authors: A
authors: A
authors: Lanzini
mesh_terms: D000328:Adult; D002446:Celiac Disease / Q000150:complications / Q000178:diet therapy* / Q000453:epidemiology / Q000473:pathology; D018592:Cross-Over Studies; D003967:Diarrhea / Q000150:complications / Q000178:diet therapy* / Q000453:epidemiology / Q000473:pathology; D055050:Diet, Gluten-Free; D004311:Double-Blind Method; D005260:Female; D005983:Glutens / Q000627:therapeutic use*; D006801:Humans; D008297:Male; D018579:Patient Selection; D012008:Recurrence
chemical_list: D005983:Glutens