Relationship between gastric inflammatory response and symptoms in patients infected with Helicobacter pylori

The Usefulness of Symptom-based Subtypes of Functional Dyspepsia for Predicting Underlying Pathophysiologic Mechanisms and Choosing Appropriate Therapeutic Agents

Functional dyspepsia (FD) is considered to be a heterogeneous disorder with different pathophysiological mechanisms or pathogenetic factors. In addition to traditional mechanisms, novel concepts regarding pathophysiologic mechanisms of FD have been proposed. Candidates of therapeutic agents based on novel concepts have also been suggested. FD is a symptom complex and currently diagnosed by symptom-based Rome criteria. In the Rome criteria, symptom-based subtypes of FD including postprandial distress syndrome and epigastric pain syndrome are recommended to be used, based on the assumption that each subtype is more homogenous in terms of underlying pathophysiologic mechanisms than FD as a whole. In this review, the usefulness of symptombased subtypes of FD for predicting underlying pathophysiologic mechanisms and choosing appropriate therapeutic agents was evaluated. Although several classic pathophysiologic mechanisms are suggested to be associated with individual dyspeptic symptoms, symptom-based subtypes of FD are not specific for a certain pathogenetic factor or pathophysiologic mechanism, and may be frequently associated with multiple pathophysiologic abnormalities. Novel concepts on the pathophysiology of FD show complex interactions between pathophysiologic mechanisms and pathogenetic factors, and prediction of underlying mechanisms of individual patients simply by the symptom pattern or symptom-based subtypes may not be accurate in a considerable proportion of cases. Therefore, subtyping by the Rome criteria appears to have limited value to guide therapeutic strategy, suggesting that the addition of objective parameters or subclassification reflecting physiologic or pathologic tests may be necessary for the targeted therapeutic approaches, particularly when therapeutic agents targeting novel mechanisms are available.

Functional dyspepsia and dyspepsia associated with Helicobacter pylori infection: Do they have different clinical characteristics?

BACKGROUND

Helicobacter pylori causes motor, secretory, and inflammatory gastrointestinal disorders and therefore the term "functional" has been questioned when referring to dyspepsia associated with this bacterium. Patients with dyspepsia and Helicobacter pylori infection could have clinical characteristics that differentiate them a priori from those with true functional dyspepsia.

AIMS

To determine whether there are clinical differences between patients with functional dyspepsia and Helicobacter pylori-associated dyspepsia that enable their a priori identification and to know the prevalence of Helicobacter pylori infection in patients with functional dyspepsia.

PATIENTS AND METHODS

A total of 578 patients with dyspepsia with no significant lesions detectable through endoscopy were divided into 2 groups according to the presence of Helicobacter pylori. The clinical characteristics, medical history, comorbidities, and use of health resources were compared between the two groups. A sub-analysis pairing the groups by age and sex in a 1:1 ratio was carried out to reduce bias.

RESULTS

A total of 336 patients infected with Helicobacter pylori were compared with 242 non-infected patients. The prevalence of infection in the patients with dyspeptic symptoms and no endoscopically detectable lesions was 58%. The initial analysis showed that the cases with dyspepsia and Helicobacter pylori infection were more frequently associated with overweight, obesity, high blood pressure, diabetes mellitus, and metabolic syndrome, but the paired analysis nullified all these differences.

CONCLUSIONS

The patients with dyspepsia infected with Helicobacter pylori had similar clinical characteristics to the non-infected patients and could not be differentiated a priori. The prevalence of Helicobacter pylori infection in patients with functional dyspepsia was 58% and increased with age.

Relationship between headache and mucosal mast cells in pediatric Helicobacter pylori-negative functional dyspepsia

BACKGROUND

Although many patients with functional dyspepsia experience headache concurrently with dyspeptic symptoms, studies suggesting mechanisms underlying this phenomenon are limited. Herein, we explore the relationship between gastrointestinal inflammatory cells and presence of headache associated with dyspeptic symptoms in children with HELICOBACTER PYLORI -negative functional dyspepsia.

METHODS

Fifty-six patients with H. PYLORI -negative functional dyspepsia underwent upper endoscopy with biopsy to investigate recurrent epigastric pain or discomfort. Patients were divided into two groups according to self-reported presence of headache associated with dyspeptic symptoms. Inflammatory cells including mast cells, and enteroendocrine cells in the gastroduodenal mucosa were evaluated. Associations between headache presence and cellular changes in the gastroduodenal mucosa were examined.

RESULTS

Headache was not associated with the grade of lymphocytes, neutrophil infiltration, or enteroendocrine cell density in the gastroduedenal mucosa. However, headache was significantly associated with high mast cell density in the body (27.81 ± 8.71 vs. 20.30 ± 8.16, P  < 0.01) and duodenum (23.16 ± 10.40 vs. 14.84 ± 5.88, P  < 0.01).

CONCLUSIONS

Presence of headache associated with dyspeptic symptoms is strongly related to mucosal mast cell density in pediatric patients with H. PYLORI -negative functional dyspepsia. Thus, our results may help clinicians understand and treat headache during dyspeptic symptoms in such pediatric patients.

What is the difference between Helicobacter pylori-associated dyspepsia and functional dyspepsia?

Advances in basic and clinical research have revealed that Helicobacter pylori (H. pylori) infection plays an important role in the development of gastroduodenal dysmotility and hypersensitivity, as also in dyspepsia symptoms. In addition, recent studies have proposed an inflammation-immunological model for the pathogenesis of functional dyspepsia. Since H. pylori is the major microbe that provokes a gastroduodenal inflammatory response, it should not be overlooked when considering the pathophysiology of dyspepsia symptoms. In fact, population-based studies have demonstrated that H. pylori is detected more frequently in dyspepsia patients. However, although many clinical studies tried to reveal the association of H. pylori infection with gastric motility dysfunction or hypersensitivity, the results have been conflicting. On the other hand, many etiological features were revealed for the development of H. pylori-associated dyspepsia, such as abnormal ghrelin or leptic secretion, altered expression of muscle-specific microRNAs, and duodenal inflammatory cell infiltration. In addition, therapeutic strategy for H. pylori-associated dyspepsia would be different from H. pylori-negative functional dyspepsia. This review focuses the issue of whether H. pylori-associated dyspepsia should be considered as a different disease entity from functional dyspepsia.

Does Helicobacter pylori-induced inflammation of gastric mucosa determine the severity of symptoms in functional dyspepsia?

BACKGROUND

Inflammation induces some structural and biochemical alterations and oxidative damage in gastric tissue. In this study, we aimed to investigate the relationship among the severity of symptoms, oxidative stress, and grading scales of Helicobacter pylori-induced gastric inflammation in functional dyspepsia.

METHODS

Thirty-five patients with functional dyspepsia were enrolled in the study. The severity of dyspepsia within the last 6 months was evaluated by Glasgow Dyspepsia Severity Score. In biopsy specimens of gastric mucosa, severity of gastritis was estimated by the revised Sydney Classification System, and oxidative stress parameters were studied.

RESULTS

Although there was no statistically significant relationship between symptom scores and degree of chronic inflammation, a tendency for symptoms to be more severe has been observed in low levels of gastritis. Levels of sulfhydryl groups were lower in subjects with high levels of chronic inflammation, and Helicobacter pylori intensity (P < 0.001 and P = 0.02, respectively). Levels of malondialdehyde were higher in subjects with high levels of chronic inflammation (P = 0.04). There was a statistically significant but a weak positive correlation between symptom scores and sulfhydryl levels (P < 0.001, r = 0.323).

CONCLUSIONS

In conclusion, there may be an inverse relation between severity of symptoms and level of Helicobacter pylori induced gastric inflammation or oxidative stress in patients with functional dyspepsia.

Halitosis in patients with Helicobacter pylori-positive non-ulcer dyspepsia: an indication for eradication therapy?

BACKGROUND: The aims of this study were to investigate the frequency of halitosis before and after eradication therapy and to determine whether halitosis is a valid indication for eradication therapy in patients with Helicobacter pylori (H. pylori)-positive non-ulcer dyspepsia. METHODS: Dyspepsia, related symptoms, and halitosis were investigated by way of a questionnaire. Only H. pylori-positive patients who showed no organic lesions on endoscopic examination and no atrophy histopathologically were included. A total of 148 patients fulfilled the above criteria and completed the study. Four weeks after the end of eradication treatment, the symptoms were re-evaluated and repeat endoscopy was done to check for H. pylori in the gastric mucosa. Results: H. pylori eradication was successful in 109 patients (73.6%). Prior to treatment, bloating was the most frequent symptom (74.3%), followed by diurnal pain (62.2%) and halitosis (61.5%). The most successfully resolved symptoms in the group as a whole, regardless of eradication status, were halitosis, diurnal pain, and hunger-like pain, respectively. In the patients with confirmed H. pylori eradication, the most successfully resolved symptoms were halitosis and hunger-like pain, respectively. CONCLUSION: Halitosis is a frequent, but treatable, symptom of H. pylori-positive non-ulcer dyspepsia and may be a valid indication for eradication therapy.

Is Helicobacter pylori associated with non-ulcer dyspepsia and will eradication improve symptoms? A meta-analysis

OBJECTIVES

To examine the association between Helicobacter pylori infection and non-ulcer dyspepsia, and to assess the effect of eradicating H pylori on dyspeptic symptoms in patients with non-ulcer dyspepsia.

DESIGN

Systematic review and meta-analysis of (a) observational studies examining the association between Helicobacter pylori infection and non-ulcer dyspepsia (association studies), and (b) therapeutic trials examining the association between eradication of H pylori and dyspeptic symptoms in patients with non-ulcer dyspepsia (eradication trials).

DATA SOURCES

Randomised controlled trials and observational studies conducted worldwide and published between January 1983 and March 1999.

MAIN OUTCOME MEASURES

Summary odds ratios and summary symptom scores.

RESULTS

23 association studies and 5 eradication trials met the inclusion criteria. In the association studies the summary odds ratio for H pylori infection in patients with non-ulcer dyspepsia was 1.6 (95% confidence interval 1.4 to 1.8). In the eradication trials the summary odds ratio for improvement in dyspeptic symptoms in patients with non-ulcer dyspepsia in whom H pylori was eradicated was 1.9 (1.3 to 2.6).

CONCLUSIONS

Some evidence shows an association between H pylori infection and dyspeptic symptoms in patients referred to gastroenterologists. An improvement in dyspeptic symptoms occurred among patients with non-ulcer dyspepsia in whom H pylori was eradicated.

Helicobacter pylori and functional dyspepsia: a real causal link?

This chapter reviews the evidence for a link between functional dyspepsia and Helicobacter pylori infection from three angles. In the section on pathophysiology, we evaluate how H. pylori could theoretically produce dyspeptic symptoms: many mechanisms can be proposed. In the discussion on epidemiology, we evaluate possible associations between the occurrence of symptoms and infection. Here, many studies claiming a coincidence or chronological sequence of infection and symptoms are criticized because of their poor design. In the section on the improvement of functional dyspepsia by the treatment of H. pylori infection, the conclusion is reached that if such an effect occurs at all--which is unlikely--it is very weak. The controversy on the link between H. pylori infection and functional dyspepsia is presently ongoing. Some authors are still trying to save an elegant concept that once looked so plausible but now has the facts against it.

Helicobacter pylori and abdominal symptoms: a population-based study among preschool children in southern Germany

OBJECTIVE

To determine the relation of Helicobacter pylori infection with gastrointestinal symptoms in a healthy population-based sample of children.

DESIGN

Population-based cross-sectional study of preschool children.

SETTING

Screening examination for school fitness by physicians of the Public Health Service in Ulm, a city with 100 000 inhabitants in southern Germany.

PARTICIPANTS

One thousand two hundred one preschool children.

MAIN OUTCOME MEASURES

Infection status was determined by 13C-urea breath test. Information on gastrointestinal symptoms was collected from children's parents by a standardized questionnaire and integrated into a symptom score. Results. Nine hundred forty-five children participated in the study (response rate, 79%). Overall, 127 children (13.4%) were infected. H pylori infection was not positively related to specific gastrointestinal symptomatology. Infected children had even fewer symptoms when compared with uninfected children.

CONCLUSIONS

Our results indicate that H pylori infection in children is mostly asymptomatic and not associated with specific gastrointestinal symptoms.

Management of dyspepsia in general practice. A critical assessment

The International Gastro Primary Care Group (IGPCG) Upper Gastrointestinal Disease Management Plan is mainly characterised by the proposal that management of patients with upper gastrointestinal syndromes be based on the predominant symptom, rather than on symptom clusters. Although no study has directly tested this hypothesis in general practice, some data indirectly support the proposal. Classification based on the relevance of specific symptoms could identify distinct subgroups of patients with functional dyspepsia with at least partially different features. Data obtained from the literature are discussed and evaluated in relation to the suggested algorithm. Overall, this management plan for patients with dyspepsia seems to be both safe and effective. However, there is a need for prospective studies evaluating its actual validity.

Association between H. pylori, duodenal mechanosensory thresholds, and small intestinal motility in chronic unexplained dyspepsia

Alterations of small intestinal sensory thresholds and small intestinal dysmotility are associated with functional dyspepsia. Because gastric and duodenal afferents partly project to the same areas, we postulated that patients with functional dyspepsia and H. pylori infection would be characterized by lower duodenal sensory thresholds. We evaluated 16 patients with functional dyspepsia and 16 age- and sex-matched controls. All patients had undergone an extensive diagnostic work-up to exclude organic lesions. Mechanosensitive function was tested in the third portion of duodenum utilizing a barostat device, and small intestinal motility was assessed before and during duodenal nutrient infusion with a five-channel low-compliance perfusion system. H. pylori status was assessed by a validated serological test. Small intestinal sensory thresholds (first perception and maximal tolerated pressure) were significantly lower in patients (21.1 +/- 2.1 and 30.9 +/- 1.8 mm Hg) compared to controls (33.0 +/- 2.2 and 38.8 +/- 0.9 mm Hg, all P < 0.003). Nine of 16 patients compared with five of 16 controls were H. pylori positive (P = 0.15). Thresholds for H. pylori-negative (28.7 +/- 2.8 and 36.5 +/- 1.1 mm Hg) or -positive subjects (25.0 +/- 3.0 and 32.7 +/- 2.4 mm Hg) were overall not significantly different (P > 0.3). However, in patients with defined high H. pylori titers (>50 units/ml) defined a priori, thresholds for first perception were significantly lower (14.7 +/- 2.9 mm Hg, N = 5) compared to patients with H. pylori titers below this threshold (24.3 +/- 2.9 mm Hg, N = 4) or without H. pylori infection (23.8 +/- 3.4 mm Hg, P < 0.05). During duodenal nutrient infusion, the duodenal motility index increased (P < 0.03). This increase was not significantly different in patients and controls or in H. pylori-negative or -positive subjects. Sensory abnormalities are present in patients with functional dyspepsia. In a small subgroup of patients with high H. pylori titers, sensory abnormalities may be linked to H. pylori infection.

Helicobacter pylori seropositivity among Swedish adults with and without abdominal symptoms. A population-based epidemiologic study

BACKGROUND

The role of Helicobacter pylori in functional dyspepsia is unclear. The aim of this population-based study was to determine whether the prevalence of H. pylori infection is higher among people with dyspepsia or irritable bowel syndrome (IBS) than among symptomless persons after control for age, sex, and socioeconomic status.

METHODS

In a postal questionnaire we asked a representative sample (20-79 years; n = 1260) from a Swedish municipality about abdominal symptoms in the preceding 3 months. A randomly selected subsample, 50 with dyspepsia, 50 with IBS, and 50 symptomless, matched with regard to age, sex, and education, were tested for the presence of IgG antibodies to H. pylori, using the HM-CAP immunoassay.

RESULTS

Fifty-five persons (38%) were H. pylori-seropositive. The seroprevalence among dyspeptics (33%) did not exceed that in healthy people (48%) or in those reporting IBS (33%). The prevalence increased with age and with lower social class, but the latter association disappeared when age was taken into account. Neither sex nor symptom intensity predicted Helicobacter seropositivity.

CONCLUSION

Our data are incompatible with an important aetiologic role for H. pylori in functional dyspepsia.

Review article: functional dyspepsia--should treatment be targeted on disturbed physiology?

In patients who present with chronic unexplained upper abdominal pain or discomfort (functional dyspepsia), therapy should ideally be targeted on correcting the individual's disturbed pathophysiology. Here, putative mechanisms implicated in functional dyspepsia and potential approaches to therapy are critically reviewed in order to determine if targeting treatment is of value. Pharmacological therapies reviewed include those that aim to correct disordered gastric emptying (e.g. cisapride, dopaminergic receptor antagonists, macrolides), reduce visceral hypersensitivity (e.g. somatostatin analogues, cholecystokinin antagonists, opioid agonists, serotonin type 3 receptor antagonists), reduce gastric acid secretion (e.g. H2-blockers, acid pump inhibitors), cure Helicobacter pylori infection, enhance muscosal defence (e.g. sucralfate, bismuth) or modify central nervous system processes. It is concluded that the imperfectly understood pathophysiology of functional dyspepsia contributes to the paucity of established efficacious therapies.

Double-blind randomized trial of bismuth subsalicylate and clindamycin for treatment of Helicobacter pylori infection

We evaluated clindamycin and bismuth subsalicylate (Pepto-Bismol) for treatment of Helicobacter pylori infection. Patients with culture or histology positive for H. pylori were randomized to receive two tablets of bismuth subsalicylate four times daily for 4 weeks or bismuth combined with 2 weeks of 300 mg clindamycin four times daily. Clinical symptoms were recorded before and after treatment by means of visual analog scales. Patients in both treatment arms showed improvement in clinical scores for abdominal pain, heartburn, and gas or bloating. Microbiologic cure was achieved in only 1 of 11 patients treated with bismuth alone and in none of 7 treated with bismuth/clindamycin. Successful eradication of H. pylori may require combination of multiple antibiotics, as recommended at the IXth World Congress of Gastroenterology, or pharmacokinetic modulators such as H2-blockers or omeprazole.