Combined analysis of the ORCHID and OCAY studies: does eradication of Helicobacter pylori lead to sustained improvement in functional dyspepsia symptoms?

Role of gut-brain axis in persistent abnormal feeding behavior in mice following eradication of Helicobacter pylori infection

Bacterial infection can trigger the development of functional GI disease. Here, we investigate the role of the gut-brain axis in gastric dysfunction during and after chronic H. pylori infection. Control and chronically H. pylori-infected Balb/c mice were studied before and 2 mo after bacterial eradication. Gastric motility and emptying were investigated using videofluoroscopy image analysis. Gastric mechanical viscerosensitivity was assessed by cardioautonomic responses to distension. Feeding patterns were recorded by a computer-assisted system. Plasma leptin, ghrelin, and CCK levels were measured using ELISA. IL-1beta, TNF-alpha, proopiomelanocortin (POMC), and neuropeptide Y mRNAs were assessed by in situ hybridizations on frozen brain sections. Gastric inflammation was assessed by histology and immunohistochemistry. As shown previously, H. pylori-infected mice ate more frequently than controls but consumed less food per bout, maintaining normal body weight. Abnormal feeding behavior was accompanied by elevated plasma ghrelin and postprandial CCK, higher TNF-alpha (median eminence), and lower POMC (arcuate nucleus) mRNA. Infected mice displayed delayed gastric emptying and visceral hypersensitivity. Eradication therapy normalized gastric emptying and improved gastric sensitivity but had no effect on eating behavior. This was accompanied by persistently increased TNF-alpha in the brain and gastric CD3(+) T-cell counts. In conclusion, chronic H. pylori infection in mice alters gastric emptying and mechanosensitivity, which improve after bacterial eradication. A feeding pattern reminiscent of early satiety persists after H. pylori eradication and is accompanied by increased TNF-alpha in the brain. The results support a role for altered gut-brain pathways in the maintenance of postinfective gut dysfunction.

Helicobacter pylori eradication in nonulcer dyspepsia: does it really matter?

One-half of the world's population has Helicobacter pylori (H. pylori) infection while dyspeptic symptoms affect one-third of the adult population, at least in the Western world. Data from epidemiological studies are controversial in terms of the association of H. pylori with non-ulcer dyspepsia (NUD) symptoms. Despite the frequency of occurrence of this clinical condition, no effective therapy exists in treating this disorder. With the strategic aim of treating NUD, a vast amount of evidence has accumulated towards eradicating H. pylori, while an equally compelling amount of evidence exists that counters this very strategy. It is, therefore, vital that there is reliable evidence for the efficacy of treatments prescribed to NUD patients. The arguments for and against the eradication of this organism continues unabated. We aim to address both sides of this fundamental divide and present the differing perspective in light of the prevalent evidence.

Development and validation of a cross-cultural questionnaire to evaluate nonulcer dyspepsia: the Porto Alegre Dyspeptic Symptoms Questionnaire (PADYQ)

Despite its high prevalence, nonulcer dyspepsia is still difficult to study, due to the lack of adequate tools to measure significant outcomes. The objective of this study was to develop and validate a symptom-focused, disease-specific questionnaire to evaluate patients with nonulcer dyspepsia. For that, the questionnaire was carefully written following widely accepted terminology, so as to facilitate translation and validation in other languages and cultures. The questionnaire was developed using Rome I terminology for symptoms, which were evaluated according to their intensity, duration, and frequency when applicable. Thirty-one patients with nonulcer dyspepsia, as well as 31 sex-and age-matched volunteers without digestive problems were used to assess the internal consistency, reproducibility, responsiveness, content validity, and discriminant validity of the questionnaire. Another 31 functional dyspeptic patients were enrolled for assessment of criterion validity. Cronbach's alpha coefficient was 0.82. The intraclass correlation coefficient for the scores obtained 7 days apart was 0.86. The mean score obtained after 3 months of treatment was 16.4, vs. 23.03 at baseline (P = 0.001). Two blinded gastroenterologists agreed that the questionnaire adequately evaluated nonulcer dyspepsia. The median symptoms score for controls was 0, vs. 22.5 for dyspeptic patients (P = 0.001). An inverse correlation was observed between quality of life and dyspeptic symptoms (R = -0.28, P = 0.026). The proposed questionnaire has high degrees of both reproducibility and responsiveness. As this questionnaire was based on Rome I International Consensus terminology, it is expected that it will be easy to translate and validate.

Gastric mucosal fibrosis: a novel explanation for dyspepsia

The etiology of functional dyspepsia has not been discerned yet which has led to inadequate treatment of this disease. It remains a common disorder with expensive and yet often ineffective therapy. We propose that the pathogenesis of this disease lies in the histological and ultrastructural changes inflicted on the gastric mucosa in chronic gastritis and fibrosis. This hypothesis, if substantiated will provide for therapy which will be based on the pathogenesis of the disease and which will be cheaper and easily available to most. It will also add impetus to the early eradication of Helicobacter pylori, which would prevent chronic gastritis and hence gastric fibrosis.

Burden of Helicobacter pylori and H. pylori-related diseases in developed countries: recent developments and future implications

Helicobacter pylori colonizes the gastric mucosa. H. pylori infection is the main cause of peptic ulcer and gastric malignancy. This review gives an overview on the epidemiology of H. pylori infection and H. pylori-associated diseases in the developed world, mainly Europe, and it discusses very recent developments with regard to the prevalence and its future implications for H. pylori-associated diseases.

New developments in the treatment of functional dyspepsia

Functional dyspepsia is a clinical syndrome defined by chronic or recurrent pain or discomfort in the upper abdomen of unknown origin. Although generally accepted, investigators differently interpret this definition and clinical trials are often biased by inhomogeneous inclusion criteria. The poorly defined multifactorial pathogenesis of dyspeptic symptoms has hampered efforts to develop effective treatments. A general agreement exists on the irrelevant role played by Helicobacter pylori in the pathophysiology of functional dyspepsia. Gastric acid secretion is within normal limits in patients with functional dyspepsia but acid related symptoms may arise in a subgroup of them. Proton pump inhibitors appear to be effective in this subset of patients with dyspepsia. Non-painful dyspeptic symptoms are suggestive of underlying gastrointestinal motor disorders and such abnormalities can be demonstrated in a substantial proportion of patients. Postprandial fullness and vomiting have been associated with delayed gastric emptying of solids, and early satiety and weight loss to postcibal impaired accommodation of the gastric fundus. Prokinetics have been shown to exert beneficial effects, at least in some patients with dyspepsia. In contrast, drugs enhancing gastric fundus relaxation have been reported to improve symptoms, although conflicting results have also been published. An overdistended antrum may also generate symptoms, but its potential pathogenetic role and the effects of drugs on this abnormality have never been investigated formally. Visceral hypersensitivity plays a role in some dyspeptic patients and this abnormality is also a potential target for treatment. Both chemo- and mechanoreceptors can trigger hyperalgesic responses. Psychosocial abnormalities have been consistently found in functional digestive syndromes, including dyspepsia. Although useful in patients with irritable bowel syndromes (IBS), antidepressants have been only marginally explored in functional dyspepsia. Among the new potentially useful agents for the treatment of functional dyspepsia, serotonin 5-HT(4) receptor agonists have been shown to exert a prokinetic effect. Unlike motilides, 5-HT(4) receptor agonists do not appear to increase the gastric fundus tone and this may contribute to improve symptoms. 5-HT(3) receptor antagonists have been investigated mainly in the IBS and the few studies performed in functional dyspepsia have provided conflicting results. Also, kappa-opioid receptor agonists might be useful for functional digestive syndromes because of their antinociceptive effects, but available results in functional dyspepsia are scanty and inconclusive. Other receptors that represent potential clinical targets for antagonists include purinoceptors (i. e., P2X2/3 receptors), NMDA receptors (NR2B subtype), protease-activated receptor-2, the vanilloid receptor-1, tachykinin receptors (NK(1)/NK(2)) and cholecystokinin (CCK)(1) receptors.