Gastrointestinal adverse reaction to food (GARF) and endoscopic confocal laser endomicroscopy (eCLE).

BACKGROUND AND STUDY AIMS: Gastrointestinal adverse reaction to food (GARF) is reported frequently in the general population and even more in patients with disorders of the gut brain axis. However, there is a significant difference between self-reported and objective proven GARF. The aim of the study was to characterize a mucosal correlate of GARF by endoscopic confocal laser endomicroscopy (eCLE) with duodenal food challenge (DFC). PATIENTS AND METHODS: In an observational and proof of concept study we evaluated 71 patients with disorders of the gut brain axis without (group I, n=19) and with (group II, n=52) GARF by eCLE and DFC. Spontaneous and food induced transfer of fluorescein into duodenal lumen was detected 10 minutes following intravenously application of fluorescein and 10 minutes after DFC. RESULTS: According to Rom IV, the patients (group I/II) could be classified as irritable bowel syndrome (IBS) 32%/31%, functional abdominal pain without changes in bowel movement 47 %/48 %, functional abdominal bloating/distension 0 %/10 %, functional diarrhea 5 %/ 2 %, and unspecified functional bowel disorder 16 %/10 %, respectively. 21 %/27 % of the patients responded with a fluorescein leakage into the duodenal lumen before and 74 %/69 % following to DFC. Frequency rank order of food components that induced a response were soy (55.5 %/60 %), wheat (60 %/45.5 %), egg (35.7 %/8.3), milk (30 %/18.2 %) and yeast (10 %/6.6 %), respectively. Histology of duodenal biopsies, number, form and distribution of intraepithelial lymphocytes and mucosal mast cells as well as mast cell function were normal. Overall, 14 %/79 % reported main symptom benefit following a food exclusion therapy according to eCLE and DFC that was significant different between the groups. CONCLUSION: The results of our study indicate that eCLE with DFC is a technique to clinically evaluate patients with disorders of the gut brain axis and GARF resulting in a high proportion of patients reporting symptom benefit upon food exclusion dietary advice focussed on the results of eCLE.

Food intolerance in patients with functional abdominal pain: Evaluation through endoscopic confocal laser endomicroscopy.

Background and study aims Gastrointestinal symptoms assumed to be caused by food intolerance are reported frequently in the general population. There is a significant difference between self-reported and objective proven food intolerance, as shown by placebo-controlled, double-blind, randomized trials. This discrepancy may be overcome by endoscopic confocal laser endomicroscopy (eCLE). Patients and methods In an observational study we evaluated 34 patients with functional abdominal pain and adverse reaction to food by eCLE and local duodenal food challenge for the first time. Spontaneous and food-induced transfer of fluorescein into the duodenal lumen was detected 10 minutes after intravenously application of fluorescein and 10 minutes after duodenal food challenge (DFC). Results Of the patients, 67.6 % responded with a fluorescein leakage into the duodenal lumen. Frequency rank order of food antigens that induced a response were soy (50 %), wheat (46.1 %), milk (20 %), egg (12 %), and yeast (11.5 %), respectively. Of the patients, 23.5 % showed spontaneous leakage of fluorescein, suggesting leaky gut syndrome. Histology of duodenal biopsies and mast cell function were normal. Overall, 69.5 % of patients improved with food exclusion therapy and 13 % were symptom-free according to eCLE. Conclusions The results of our study indicate that eCLE is a clinically useful tool to evaluate patients with functional abdominal pain and adverse reaction to food and to create individualized dietary therapy with clinical benefit for patients.

Endoscopic laser endomicroscopy and "leaky gut" in patients with functional gastrointestinal symptoms and food intolerance.

BACKGROUND: Intestinal epithelial barrier dysfunction ("leaky gut syndrome", LGS) is thought to play a major role in the pathogenesis of disorders of the gut brain axis. Endoscopic confocal laser endomicroscopy (eCLE) is an objective measure to test duodenal permeability. We applied this technique in patients with functional gastrointestinal symptoms and food intolerance to characterize the proportion of patients with LGS. MATERIAL AND METHODS: In an observational study, we evaluated 85 patients with functional gastrointestinal symptoms and food intolerance. Gastrointestinal symptoms were classified according to Rom IV into functional abdominal pain (FAP), irritable bowel syndrome (IBS), irritable bowel syndrome diarrhea dominant (IBS-D), irritable bowel syndrome constipation dominant (IBS-C), irritable bowel syndrome with mixed stool (IBS-M), functional abdominal bloating (FAB), functional diarrhea (FD) and unclassified (NC). During eCLE, spontaneous transfer of intravenously applied fluorescein into duodenal lumen (LGS) and following duodenal food challenge (DFC) were analyzed. Blood analysis comprised parameters of mast cell function, histology of duodenal mucosal biopsies analysis of mucosal inflammation, intraepithelial lymphocytes (IELs) as well as number, distribution and morphology of mast cells. RESULTS: 24 patients (9 IBS, 9 FAP, 3 FAB, 1 FD, 2 NC), showed LGS, 50 patients (14 IBS-D, 4 IBS-C, 3 IBS-M, 23 FAP, 3 FAB, 3 NC) had no LGS but responded to DFC and 11 patients (6 NC, 3 FAP, 1 FAB, 1 FD) had no LGS and no response to DFC. The proportion of subgroups with/or without spontaneous leakage of fluorescein (+LGS/-LGS) were IBS-LGS/IBS+LGS 67%/33%, FAP-LGS/FAP+LGS 72%/28%,FAB-LGS/FAB+LGS 50%/50%, NC-LGS/NC+LGS 60%/40%. Subgroup analysis revealed no significant differences for all parameters tested. CONCLUSION: As a proof of concept, the results of our study indicate that eCLE is a clinical useful tool to evaluate patients with disorders of the gut brain axis and those suspicious of LGS. However, the clinical significance of LGS remains unclear. The study should be an incentive to perform a randomized study including healthy controls.

Tolerability of FODMAP - reduced diet in irritable bowel syndrome - efficacy, adherence, and body weight course.

BACKGROUND: FODMAP reduced diet (fermentable oligo-, di-, monosaccharide, and polyols) belongs to the established therapy strategies in irritable bowel syndrome (IBS). However, disadvantages of this diet are significant and may lead to weight loss and insufficient patient adherence. Reports from Germany are not available yet. MATERIAL AND METHODS: In a prospective study, 93 patients with IBS according to Rom III were investigated. Sixty-three patients were recruited for the study and received standardized investigation, informed consent, and structured dietary instructions about the FODMAP reduced diet. Patients complaints were documented by a validated questionnaire and a standardized Lickert scale before and 8 weeks after the start of the diet. Stool characteristics were documented by the Bristol stool form scale. RESULTS: Patients adherence was low because 30 patients (47 %) stopped the diet. Of the remaining 33 patients, 36 % (n = 12) developed significant weight loss during the FODMAP therapy. Patients completing the study reported significant global improvement of symptoms in 79 % of cases (abdominal pain 85 %, meteorism 79 %, flatulence 69 %, borbogymi 69 %, nausea 46 %, fatigue 69 %). In addition, the severity of symptoms was significantly reduced. Fourteen patients developed changes of their stool characteristics according to the Bristol stool form scale, 11 of whom improved diarrhea and 3 improved constipation. CONCLUSION: FODMAP reduced diet is an efficient therapy in IBS. However, adherence of the patients is poor and the therapy bears the risk of significant weight loss.