Persistent symptoms in patients with Crohn's disease in remission: An exploratory study on the role of diet.

OBJECTIVES: Patients with Crohn's disease (CD) often report food hypersensitivities with gastrointestinal (GI) symptoms despite being in clinical remission. We aimed to identify the most frequent symptoms and dietary triggers in such patients, and also explored whether a strict elimination diet may reduce their GI symptoms. METHODS: We assessed GI symptoms and dietary triggers in 16 patients with CD in clinical remission. Of these, 12 patients subsequently participated in a dietary intervention trial: two weeks on a habitual diet including wheat and dairy products followed by two weeks of a strict elimination diet. The severity of seven symptoms (overall symptoms, abdominal pain, bloating, abnormal feces, wind, fatigue, and musculoskeletal pain) was measured by using visual analog scales throughout the four weeks intervention period. MAIN RESULTS: The most common symptoms were abdominal pain, wind, bloating, odorous wind/feces, and diarrhea. Dairy and wheat products were reported as the most frequent dietary symptom triggers. All symptoms improved (p < .05) during the elimination diet period, especially in patients with small intestinal affection. CONCLUSION: Our exploratory study suggests that dietary interventions such as an elimination diet may reduce GI symptoms in patients with CD in remission.

Exploring Gut Microbiota Composition as an Indicator of Clinical Response to Dietary FODMAP Restriction in Patients with Irritable Bowel Syndrome.

BACKGROUND: A diet low in fermentable oligosaccharides, disaccharides, monosaccharides, and polyols (FODMAPs) may relieve symptoms of irritable bowel syndrome (IBS). However, nutritional counseling is resource-demanding and not all patients will benefit. AIMS: To explore whether gut microbial composition may identify symptom response to a low-FODMAP diet in patients with IBS. METHODS: Patients were recruited consecutively to participate in a 4-week FODMAP-restricted diet. Response to diet was defined as ≥ 50% decrease in IBS symptom severity scores (IBS-SSS) compared to baseline. Fecal microbiota were analyzed by a commercially available method (the GA-map™ Dysbiosis Test), assessing 54 bacterial markers targeting more than 300 bacteria at different taxonomic levels. RESULTS: Sixty-one patients (54 F; 7 M) were included: 32 (29 F; 3 M) classified as responders and 29 (25 F; 4 M) as non-responders. Ten of the 54 bacterial markers differed significantly between responders and non-responders. Based on median values (used as cutoff) of responders for these 10 bacterial markers, we constructed a Response Index (RI): Each patient was given a point when the value for each selected bacterial marker differed from the cutoff. These points were summed up, giving an RI from 0 to 10. Patients with RI > 3 were 5 times more likely to respond (OR = 5.05, 95% CI [1.58; 16.10]), and the probability to respond was 83.4%, 95% CI [61.2-94%]. CONCLUSIONS: Gut microbial composition, assessed by using a new RI, may constitute a tool to identify patients that are likely to respond to dietary FODMAP restriction.

Fecal Fermentation in Irritable Bowel Syndrome: Influence of Dietary Restriction of Fermentable Oligosaccharides, Disaccharides, Monosaccharides and Polyols.

BACKGROUND/AIMS: Dietary restriction of fermentable oligosaccharides, disaccharides, monosaccharides and polyols (FODMAPs) may relieve symptoms in patients with irritable bowel syndrome (IBS). We investigated whether this diet alters microbial fermentation, a process that may be involved in IBS symptom generation. METHODS: Patients with IBS were included consecutively to participate in a 4-week FODMAP restricted diet. IBS symptoms were evaluated by using the IBS severity scoring system (IBS-SSS). Short-chain fatty acids (SCFAs) were analyzed in fecal samples before and after the dietary intervention, both at baseline and after in vitro fermentation for 24 h. RESULTS: Sixty-three patients completed the study. Following the dietary intervention, IBS-SSS scores improved significantly (p < 0.0001). Total SCFA levels were reduced in fecal samples analyzed both at baseline (p = 0.005) and after in vitro fermentation for 24 h (p = 0.013). Following diet, baseline levels of acetic (p = 0.003) and n-butyric acids (p = 0.009) decreased, whereas 24 h levels of i-butyric (p = 0.003) and i-valeric acids (p = 0.003) increased. Fecal SCFA levels and IBS symptom scores were not correlated. CONCLUSION: Dietary FODMAP restriction markedly modulated fecal fermentation in patients with IBS. Saccharolytic fermentation decreased, while proteolytic fermentation increased, apparently independent of symptoms.