Helicobacter pylori and dyspepsia

It is clear that non-ulcer (or functional) dyspepsia is a heterogeneous syndrome that includes a subset of patients with unrecognized gastroesophageal reflux. Patient heterogeneity combined with inadequate study methodology has led to enormous confusion in interpreting the relationship between Helicobacter pylori and non-ulcer dyspepsia. The possibility that H. pylori is associated with gastroesophageal reflux disease may explain, in part, the difficulty in establishing a link between non-ulcer dyspepsia and H. pylori infection. It is unclear whether the prevalence of H. pylori is increased in non-ulcer dyspepsia over and above the background population. H. pylori does not appear to be linked to heartburn or other specific upper gastrointestinal tract symptoms. The results of eradication trials in H. pylori-infected patients with non-ulcer dyspepsia have been equivocal and generally flawed. There is no doubt that H. pylori is not a sufficient cause of non-ulcer dyspepsia, because it is well documented in the literature that dyspepsia can occur in the absence of infection and infection can occur in the absence of symptoms. At this stage, there is insufficient evidence to support the hypothesis that H. pylori is etiologically linked to non-ulcer dyspepsia, but data from well designed large randomized controlled trials of eradication therapy, are awaited with great interest.     

Eradicating Helicobacter pylori and symptoms of non-ulcer dyspepsia.

OBJECTIVE--To examine the effect of eradication of Helicobacter pylori on symptoms of non-ulcer dyspepsia. DESIGN--Four week prospective study. SETTING--One hospital outpatient and endoscopy department. PATIENTS--90 adults with persistent symptoms typical of non-ulcer dyspepsia but no clinical or endoscopic evidence of other peptic, biliary, pancreatic, or malignant disease; all had histological and microbiological evidence of infection with H pylori. 83 patients completed the treatment regimen. INTERVENTION--Colloidal bismuth subcitrate 120 mg four times a day for four weeks (27 patients); metronidazole 400 mg and amoxycillin 500 mg each three times a day for one week (27); and bismuth subcitrate 120 mg four times a day for four weeks, metronidazole 400 mg three times a day for one week, plus amoxycillin 500 mg three times a day for the first week (29). MAIN OUTCOME MEASURES--Change in symptom scores determined with questionnaire; histological evidence of gastritis and microbiological evidence of presence of H pylori in biopsy specimens. RESULTS--Overall, H pylori was eradicated in 41 (49%) patients. Although gastritis scores improved significantly in only patients in whom H pylori had been eradicated (from 1.56 to 0.61, p less than 0.01 v from 1.83 to 1.07, p = 0.52) mean symptom scores after treatment were similar in patients in whom H pylori had or had not been eradicated (3.0 v 2.3, NS). Similarly the mean symptom score improved whether or not gastritis improved (2.8 v 3.1 respectively, p = 0.72). The observations were similar for treatment groups analysed individually. CONCLUSION--Antral infection with the organism does not seem to have an important aetiological role in non-ulcer dyspepsia short term.     

Seroprevalence and risk factors for Helicobacter pylori infection in Greenlanders

BACKGROUND: In contrast to most populations worldwide, the incidence of gastric cancer increases among Inuit in Greenland. Contributing factors to this increase are unknown, but Helicobacter pylori may be involved. However, little is known regarding the epidemiology of H. pylori in Arctic communities. With the aim of determining age-specific prevalence, risk factors, and association with clinical conditions of H. pylori infection, we carried out a population-based study of H. pylori in Sisimiut, the second biggest town of Greenland. MATERIALS AND METHODS: A population-based sample of 685 persons had serum drawn that was analyzed for H. pylori IgG antibodies using enzyme-linked immunosorbent assay (ELISA). Risk factors analyses were carried out using multivariate logistic regression models. RESULTS: The seroprevalence was lowest among children aged 0-4 years (6%), but increased rapidly thereafter. In persons aged 15-87 years the seroprevalence had stabilized around 58%. Total number of children in household, number of older, but not younger, siblings and narrow age gap to closest older sibling were associated with H. pylori seropositivity. In contrast, number of adults in household and socioeconomic status did not influence serostatus. CONCLUSIONS: The age-specific prevalence pattern in Greenland is intermediate between that of developing and developed countries. The risk factor pattern indicates crowding and older siblings in particular to be key elements in risk of infection.     

Helicobacter pylori infection in childhood: risk factors and effect on growth.

OBJECTIVE--To investigate the current prevalence of Helicobacter pylori infection in childhood, the risk factors for infection, and the effect of infection on growth in preadolescent schoolchildren. DESIGN--Population based sample of 7 year old schoolchildren followed up at age 11; data on risk factors for infection collected at age 7; presence of infection at age 11 determined by measurement of salivary IgG against H pylori by a newly developed enzyme linked immunosorbent assay (ELISA). Height was measured at 7 and 11 years of age. SUBJECTS--554 schoolchildren from Edinburgh. RESULTS--62 (11%) children had H pylori infection. Independent risk factors for infection were single parent families (adjusted odds ratio = 2.5; 95% confidence interval 1.1 to 5.7), the 10% most crowded homes (3.1; 1.3 to 7.2), and schools serving predominantly rented housing estates (2.5; 1.0 to 6.5). School catchment area was more important than parental social class or housing tenure. Growth in height between 7 and 11 was diminished in infected children by a mean of 1.1 cm (0.3 to 2.0 cm) over four years. This growth reduction was largely confined to girls (1.6 cm over four years), among whom it correlated with salivary IgG (P = 0.015). CONCLUSION--Data from salivary assay to investigate the epidemiology of H pylori suggest that factors relating to the type of community in which the child lives may now be as important for acquisition of this infection as features of the family home. The greater reduction of growth among infected girls raises the possibility that H pylori infection may delay or diminish the pubertal growth spurt.     

Prevalence and risk factors for Helicobacter pylori infection in Chinese populations

Background:  The prevalence of Helicobacter pylori is higher in developing countries. The aim of this study was to investigate the prevalence and risk factors of H. pylori infection in areas with high prevalence of gastric cancer in Jiangsu Province, China.
Methods:  A prospective epidemiologic survey of H. pylori infection was accomplished in a natural population of 1457 individuals in Xiangshui and Gaoyou counties, Jiangsu Province, China. Questionnaires and laboratory tests for H. pylori infection (¹³C-urea breath test and serum IgG antibodies to H. pylori ) were used and performed, respectively.
Result:  Among 1371 subjects who completed questionnaires and H. pylori detection, 851 (62%) were H. pylori positive. The prevalence reached a peak at the age of 30–40 years (67%). There was no sex difference. The annual family income level was shown to be positively correlated with the risk of H. pylori infection. The prevalence of H. pylori infection was also associated with family size, education level, and several diet-related factors, such as the number of times cooked rice and potatoes eaten per week, and a family history of stomach diseases. Compared to nonsymptomatic individuals, people with dyspeptic symptoms (nausea, vomiting, and belching) presented a low prevalence of H. pylori infection. No association between H. pylori prevalence and smoking or drinking was found. Using multivariate logistic regression analysis, annual family income and education level were the independent predictors for H. pylori infection.
Conclusion:  High prevalence of H. pylori infection was found in areas with a high risk of gastric cancer and was related to several risk factors. The underlying mechanisms need to be further investigated.     

Eradication of Helicobacter pylori infection in the management of patients with dyspepsia and non-ulcer dyspepsia.

Although H. pylori infection has been recognized as a major etiological agent for the development of chronic active gastritis, duodenal ulcer and benign non-NSAID related gastric ulcer, its role in the development of symptoms in patients with dyspepsia remains uncertain. Results from population-based epidemiological studies have been conflicting regarding a causal link between H. pylori infection and dyspepsia. Abnormalities in gastric acid secretion may exist in some dyspeptic patients. Whether disordered gastric motility seen in dyspeptic patients is related to the infection is not clear based on the results in the literature. Numerous clinical trials have been undertaken to eradicate H. pylori infection and improve the symptoms in dyspeptic patients; however, the results have been discrepant between studies. Many published studies suffer from methodological problems that have made interpretation difficult. Large, well-conducted, randomized, placebo-controlled, clinical trials with long-term follow-up are needed to justify the beneficial effect of H. pylori eradication treatment in dyspeptic patients seen in some small studies. H. pylori eradication therapy is cost-effective in H. pylori-infected dyspeptic patients although this benefit may take a long time to accrue, especially in younger patients.     

Cardiovascular risk factors in subjects with Helicobacter pylori infection

Background. It has been proposed that Helicobacter pylori infection is related to cardiovascular disease, although this has not been fully investigated. The aim of this study was to investigate whether H. pylori in‐fection is associated with cardiovascular risk factors. Subjects and Methods. One thousand six hundred and fifty people undergoing annual medical checks at Shimane Institute of Health Science between September 1998 and August 1999 were enrolled. Gender, age, body mass index, habitual smoking and drinking, systolic and diastolic blood pressure, serum level of total cholesterol, triglyceride, high‐density lipoprotein cholesterol (HDLC), blood glucose, leukocyte count and hemoglobin were compared between H. pylori seropositive and seronegative cases. Results. In H. pylori seropositive individuals, HDLC was significantly lower than that in seronegative individuals. After adjustment for possible confounding factors (gender, age, BMI, smoking and drinking habits), mean HDLC in H. pylori‐seropositive and seronegative individuals were 56.1 and 58.2 mg/dl, respectively (p < .005). The percentage of the elderly (over 50 years old) individuals with HDLC < 35 mg/dl in H. pylori seropositive and seronegative groups were 7.4% and 4.7%, respectively (p < .001). In addition, the lower HDLC level was accompanied by an increased leukocyte count. Conclusion. Long‐term infection with H. pylori may have an important role in decreasing the serum HDLC concentration.     

Prevalence of Helicobacter pylori in Georgian patients with dyspepsia

BACKGROUND: Georgia has showed a high prevalence of peptic ulcer disease (PUD), but the prevalence of Helicobacter pylori in this country is practically unknown. The purpose of this study was to determine the prevalence of H. pylori and specific genotypes in different populations in Georgia. MATERIALS AND METHODS: We studied 62 patients from several hospitals in Tbilisi, Georgia. More than 55% of patients had PUD. We determined H. pylori presence as well as specific genotypes cagA and vacA by polymerase chain reaction. In addition, we studied serum samples from 94 healthy persons to determine H. pylori and CagA prevalence by ELISA. RESULTS: We found a high prevalence of H. pylori and CagA in the healthy population (70.2 and 57.4%, respectively) and a high prevalence of CagA among the H. pylori-positive persons (71.2%). Prevalence increased with age as reported in other countries (p = .05). Among symptomatic persons, we found nearly the same high prevalence of H. pylori (64.5%) as in the asymptomatic population. Furthermore, in symptomatic H. pylori patients, we found 65.0 and 67.5% prevalence of cagA and vacA, respectively. For 33 patients with PUD, 24 patients (72.7%) were H. pylori positive and 66.7% of them were cagA positive. In contrast, among the patients with non-ulcer dyspepsia (NUD), 16 (55.2%) were H. pylori positive and 62.5% of them were colonized with cagA-positive strains. H. pylori and cagA prevalence were not significantly different between PUD and patients with NUD. CONCLUSIONS: We confirmed that among individuals in Georgia, the prevalence of H. pylori is high and cagA-positive strains were equally present among H. pylori-positive patients with PUD and NUD and asymptomatic persons.     

Persistence factors of Helicobacter pylori

Isolates of H. pylori from patients with chronic gastritis and peptic ulcer, were found to be capable of inactivating lysozyme and intercide (the bactericidal component of human leukocytic interferon). The expression and penetration capacity of their antilysozyme activity (ALA) and antiintercide activity was determined. The wide spread of ALA among H. pylori clinical isolates associated with inflammatory changes in bioptic specimens, confirmed the leading role of this microorganism in the pathogenesis of the gastric mucosal lesions. The retrospective analysis of clinical cases made it possible to recommend the use of the ALA sign as one of the criteria for choosing the scheme of eradication therapy even at the stage of the initial diagnostics of H. pylori infection.     

Virulence factors of Helicobacter pylori: implications for vaccine development

Helicobacter pylori is one of the most common infectious diseases in humans and causes gastritis, peptic ulcer disease and malignant tumours of the stomach. This review discusses how H. pylori can colonize the human stomach, an ecological niche that is protected against all other bacteria. Knowledge about the virulence factors of H. pylori has accumulated rapidly over the last decade. Together with the information contained in the complete H. pylori genome sequence, this knowledge is now being applied in the search for a vaccine against this global pathogen.     

Helicobacter pylori: bacterial factors and interaction with the epithelial cells.

Helicobacter pylori has been recognized as a major cause of most of the diseases of the stomach. These diseases are preceded by lesions of gastritis induced by H. pylori. This long-standing infection gives us a very good model of interaction between a bacterium and its host. We will review the direct and indirect effects of H. pylori.     

Randomised controlled trial of Helicobacter pylori testing and endoscopy for dyspepsia in primary care

ObjectiveTo determine the cost effectiveness of a strategy of near patient Helicobacter pylori testing and endoscopy for managing dyspepsia.DesignRandomised controlled trial.Setting31 UK primary care centres.Participants478 patients under 50 years old presenting with dyspepsia of longer than four weeks duration.InterventionsNear patient testing for H pylori and open access endoscopy for patients with positive results. Control patients received acid suppressing drugs or specialist referral at general practitioner''s discretion.Results40% of the study group tested positive for H pylori. 45% of study patients had endoscopy compared with 25% of controls. More peptic ulcers were diagnosed in the study group (7.4% v 2.1%, P=0.011). Paired comparison of symptom scores and quality of life showed that all patients improved over time with no difference between study and control groups. No significant differences were observed in rates of prescribing, consultation, or referral. Costs were higher in the study group (£367.85 v £253.16 per patient).ConclusionsThe test and endoscopy strategy increases endoscopy rates over usual practice in primary care. The additional cost is not offset by benefits in symptom relief or quality of life.

What is already known on this topic

Patients younger than 50 without H pylori infection are unlikely to have treatable disease detected at endoscopySuch patients can be managed by acid suppression and reassurance aloneTest and endoscopy (referral of patients testing positive for H pylori in primary care) has been recommended as a way to reduce endoscopic workload

What this paper adds

Applying a test and endoscopy strategy increased the endoscopy referral rate from 25% to 40%The strategy produced no significant differences in symptoms or quality of life compared with usual managementThe increased costs of this strategy cannot be justified     

Molecular and cellular activities of Helicobacter pylori pathogenic factors.

Stomach infection with pathogenic strains of Helicobacter pylori causes in some patients severe gastroduodenal diseases. These bacteria produce various virulence factors and, here, we review the recent acquisition on the biochemical mode of action of three major factors. We discuss the role of urease both as buffer of the stomach pH and as source of ammonia. The vacuolating toxin alters the endocytic pathway of non-polarized cells, inducing the release of acid hydrolases, the depression of extracellular ligand degradation and of antigen processing and, in the presence of ammonia, swelling of late-prelysosomal compartments. In polarized epithelial monolayers, vacuolating toxin induces an increase of the paracellular permeability, independent of vacuolation. The neutrophil activating protein induces the production of oxygen radicals in human neutrophils and could contribute to the damage of the stomach mucosa. The activities of these factors are discussed in terms of the need of the bacterium of increasing the supply of nutrients from the stomach lumen and from the mucosa.     

根除幽门螺杆菌对老年功能性消化不良的治疗作用

目的 探讨根除幽门螺杆菌(H. pylori)对老年功能性消化不良(functional dyspepsia,FD)的治疗效果。 方法 选取2016年3月至2018年4月我院诊治的92例老年FD合并H. pylori阳性患者进行研究,采用随机分组表分为常规组(常规促进胃动力治疗,46例)和干预组(常规治疗联合H. pylori根除治疗,46例),比较两组患者治疗前后症状评分、疗效及药物不良反应发生率。 结果 治疗前,常规组和干预组患者上腹不适、饱胀感、灼烧感评分比较差异无统计学意义(均P>0.05)。治疗14 d,两组患者上腹不适、饱胀感、灼烧感评分均下降,且干预组患者下降程度更大(均P2=5.134 2,P=0.023 5)。两组患者治疗14 d期间,口干、恶心呕吐、头晕、皮疹、乏力发生率比较差异无统计学意义(均P>0.05)。 结论 对老年FD合并H. pylori阳性患者实施H. pylori根除性治疗能协助改善患者消化不良症状,提高患者疗效,同时不增加药物不良反应发生率。     

Helicobacter pylori recrudescence and its influencing factors

Helicobacter pylori (H pylori) is known as one of the most common infectious pathogens, with high infection and recurrence rates worldwide. The prevalence of H pylori is up to 90% in developing countries, while the annual recurrence rate is much higher than that in developed countries. Recurrence can occur either by recrudescence or reinfection. Compared with reinfection, the time window for recrudescence is generally shorter, followed by the recurrence of H pylori–associated diseases in the short‐term. Many factors are involved in the H pylori reinfection, such as the prevalence of H pylori infection, living conditions and economic development, health conditions and so forth. Previous studies focused less on H pylori recrudescence. Therefore, the influencing factors for H pylori recrudescence needed further exploration. This study reviewed the recrudescence of H pylori infection and its influencing factors.