A leading hypothesis for the role of bacteria in inflammatory bowel diseases is that an imbalance in normal gut flora is a prerequisite for inflammation. Testing this hypothesis requires comparisons between the microbiota compositions of ulcerative colitis and Crohn's disease patients and those of healthy individuals. In this study, we obtained biopsy samples from patients with Crohn's disease and ulcerative colitis and from healthy controls. Bacterial DNA was extracted from the tissue samples, amplified using universal bacterial 16S rRNA gene primers, and cloned into a plasmid vector. Insert-containing colonies were picked for highthroughput sequencing, and sequence data were analyzed, yielding species-level phylogenetic data. The clone libraries yielded 3,305 sequenced clones, representing 151 operational taxonomical units. There was no significant difference between floras from inflamed and healthy tissues from within the same individual. Proteobacteria were significantly (P ‫؍‬ 0.0007) increased in Crohn's disease patients, as were Bacteroidetes (P < 0.0001), while Clostridia were decreased in that group (P < 0.0001) in comparison with the healthy and ulcerative colitis groups, which displayed no significant differences. Thus, the bacterial flora composition of Crohn's patients appears to be significantly altered from that of healthy controls, unlike that of ulcerative colitis patients. Imbalance in flora in Crohn's disease is probably not sufficient to cause inflammation, since microbiotas from inflamed and noninflamed tissues were of similar compositions within the same individual.

This document addresses the design of trials to assess the efficacy of new treatments for functional gastrointestinal disorders (FGID), emphasizing trials in irritable bowel syndrome and dyspepsia, because most research has been undertaken in these conditions. The double-blind, randomized, placebo-controlled, parallel group trial remains the preferred design. Randomized withdrawal designs, although encouraged by the European Agency for the Evaluation of Medicinal Products, have the same potential disadvantages as a crossover design, including carryover effects, unmasking (unblinding), and overestimation of the potential benefit for clinical practice. Innovative trial designs that evaluate intermittent (on demand) treatment are likely to become more common in the future. Investigators should include as broad a spectrum of patients as possible and should report recruitment strategies, inclusion/exclusion criteria, and attrition data. The primary analysis should be based on the proportion of patients in each treatment arm who satisfy an a priori treatment responder definition, or a prespecified clinically meaningful change in a patient-reported symptom improvement measure. Such measures of improvement are psychometrically validated subjective global assessments or a change from baseline in a validated symptom severity questionnaire. It is unethical to change the responder definition after a trial begins. Data analysis should address all patients enrolled, using an intention-to-treat principle. Reporting of results should follow the Consolidated Standards for Reporting Trials guidelines and include an analysis of harms data and secondary outcome measures to support or explain the primary outcome. Trials should be registered in a public location, prior to initiation, and should be published even if the results are negative or inconclusive.

Summary Background: Uninvestigated dyspepsia is common in family practice. The prevalence of clinically significant upper gastrointestinal findings (CSFs) in adult uninvestigated dyspepsia patients, and their predictability based on history, is unknown. Methods: Prompt endoscopy was performed within 10 days of referral, in 1040 adult patients presenting with uninvestigated dyspepsia at 49 Canadian family practitioner centres. Subsequent management strategies during a 6‐month follow‐up period were determined by the individual family practitioners. Results: CSFs were identified in 58% (603/1040) of patients. Erosive oesophagitis was most common (43%; N = 451); peptic ulcer was uncommon (5.3%; N = 55). Alarm symptoms were uncommon (2.8%; N = 29). Most patients had at least three dyspepsia symptoms, more than 80% had at least six, and approximately half had eight or more. Based on the dominant symptom, 463 (45%) patients had ulcer‐like, 393 (38%) had reflux‐like and 184 (18%) had dysmotility‐like dyspepsia. The patients' dominant symptom was not predictive of endoscopic findings. Oesophagitis was more common in those with dominant reflux‐like symptoms and was the most common finding in all subgroups. The prevalence of gastroduodenal findings was similar in all symptom subgroups. Helicobacter pylori (H. pylori) infection (30%; 301/1013) was associated with gastroduodenal findings. Conclusions: Dyspepsia subclassifications, based on dominant symptom, are of limited value in predicting the presence and nature of CSFs. Oesophagitis was by far the most common diagnosis (43% of patients). CSFs were common in uninvestigated dyspepsia patients and their nature suggests patients could be initially treated effectively, without endoscopy, using empirical acid suppressive therapy.

Prospective studies are needed to investigate clinically relevant risk factors for the development of GERD and its complications; GERD progression, on and off therapy; optimal management strategies for typical GERD symptoms in primary care patients; and optimal management strategies for atypical GERD symptoms, Barrett's epithelium and esophageal adenocarcinoma.