Clinical and Microbiological Effect of a Multispecies Probiotic Supplementation in Celiac Patients With Persistent IBS-type Symptoms A Randomized, Double-Blind, Placebo-controlled, Multicenter Trial

Goals: The goals of this study were to evaluate the efficacy and safety of a probiotic mixture in patients with celiac disease (CD) with irritable bowel syndrome (IBS)-type symptoms despite a strict gluten-free diet (GFD). Background: About 30% of patients with CD adherent to a GFD suffer from IBS-type symptoms; a possible cause resides in the imbalances of the intestinal microbiota in CD. Probiotics may represent a potential treatment. Study: CD patients with IBS-type symptoms entered a prospective, double-blind, randomized placebo-controlled study. A 6-week treatment period was preceded by a 2-week run-in and followed by a 6-week follow-up phase. Clinical data were monitored throughout the study by validated questionnaires: IBS Severity Scoring System (IBS-SSS); Gastrointestinal Symptom Rating Scale (GSRS); Bristol Stool Form Scale (BSFS); and IBS Quality of Life Questionnaire (IBS-QOL). The fecal microbiota were assayed using plate counts and 16S rRNA gene-based analysis. Results: In total, 109 patients were randomized to probiotics (n= 54) or placebo (n= 55). IBS-SSS and GSRS decreased significantly in probiotics, as compared with placebo [(-15.9%+/- 14.8% vs. 8.2%+/- 25.9%; P< 0.001) and (-19.8%+/- 16.6% vs. 12.9%+/- 31.6%; P< 0.001)], respectively. Treatment success was significantly higher in patients receiving probiotics, as compared with placebo ( 15.3% vs. 3.8%; P< 0.04). Presumptive lactic acid bacteria, Staphylococcus and Bifidobacterium, increased in patients receiving probiotic treatment. No adverse events were reported. Conclusions: A 6-week probiotic treatment is effective in improving the severity of IBS-type symptoms, in CD patients on strict GFD, and is associated with a modification of gut microbiota, characterized by an increase of bifidobacteria.