Effect of eradication of Helicobacter pylori on gastric juice ascorbic acid concentrations.

Ascorbic acid, the reduced form of vitamin C, may protect against gastric cancer and is secreted by the normal stomach. Secretion is impaired in Helicobacter pylori (H pylori) associated chronic gastritis. This study examined if eradication of H pylori improves gastric juice ascorbate values. Fasting gastric juice and plasma samples were collected at endoscopy from patients participating in trials of H pylori eradication for duodenal ulcer disease and intestinal metaplasia before and up to 15 months after attempted eradication. Ascorbic acid and total vitamin C concentrations were determined by high performance liquid chromatography. In 12 patients in whom H pylori was successfully eradicated gastric juice ascorbate and total vitamin C concentrations and the ratio of juice to plasma vitamin C rose after treatment. Analysis after treatment suggested that the rise was greatest in patients with high final plasma vitamin C concentrations, even though these did not change with treatment. By contrast, in 22 patients in whom H pylori eradication was unsuccessful there were no significant changes in juice or plasma concentrations after treatment. It is concluded that successful eradication of H pylori improves secretion of vitamin C into gastric juice. It is speculated that this increases protection against gastric cancer.     

Effect of Helicobacter pylori eradication on gastric mucosal phospholipid content and its fatty acid composition

BACKGROUND AND AIMS: Whether Helicobacter pylori eradication alters gastric mucosal phospholipid contents and their fatty acid composition remains unclear. The aim of the present study was to clarify the effect of H. pylori eradication on gastric mucosal phosphatidylcholine (PC) content and its fatty acid composition. METHODS: Endoscopic biopsy specimens were taken from the antrum and body of each of 19 asymtomatic male volunteers for detection of H. pylori, histopathological assessment of gastritis, phospholipid determination and fatty acid analysis. All the subjects with H. pylori infection were treated with eradication therapy. Endoscopy and tissue sampling were repeated again 1 and 6 months after all treatment. RESULTS: In eight subjects, H. pylori infection was evident and was successfully eradicated. Pretreatment degrees of lymphocytes and plasma cells (inflammation) and polymorphonuclear neutrophils (activity) were greater in H. pylori-positive subjects compared with H. pylori-negative subjects (P<0.001), whereas the degree of inflammation decreased (P<0.001), and neutrophils had completely disappeared at 6 months after eradication. Moreover, the gastric mucosal PC contents at the antrum and body were unchanged within 1 month after cessation of treatment, but increased at 6 months after eradication (P<0.05). At 6 months after cessation of treatment, H. pylori-eradicated subjects had an increase (+30% at antrum, +18% at body) in linoleic acid composition and a decrease (-37%, -43%) in arachidonic acid composition of PC at the antrum and body, respectively. CONCLUSIONS: These findings suggest that H. pylori eradication reduces the production of various eicosanoids, resulting in the normalization of gastric mucosal PC content and its fatty acid composition, which may consequently cause the gastric mucosal hydrophobicity to be normalized.     

Effect of Helicobacter pylori eradication on gastric metaplasia of the duodenum.

Helicobacter pylori associated duodenal ulcers occur in patches of gastric metaplasia. The pathogenesis of gastric metaplasia is unclear, but it has been produced in experimental animals by acute injury and has been shown to be present to a greater extent of H pylori positive subjects. This study aimed to discover if gastric metaplasia regressed with eradication of H pylori or healing of duodenal ulcers, or both. Thirty two duodenal ulcer patients with H pylori infection confirmed by biopsy urease test and by antral histological examination were studied. Patients were treated with triple therapy (deNol 240 mg twice daily, amoxycillin 500 mg three times daily, and metronidazole 400 mg three times daily) for two weeks after the first endoscopy and were subsequently re-endoscoped. Three duodenal bulb biopsy specimens were obtained per patient at each endoscopy. Biopsy sections were stained with haematoxylin and eosin to determine the severity of duodenitis, and with diastase periodic acid-Schiff/alcian blue to assess the extent of gastric metaplasia. Slides were assessed by two histopathologists unaware of treatment status. H pylori was eradicated in 63% of subjects and all ulcers were healed at follow up. The median extent of gastric metaplasia at the start of treatment and 6-18 months (median 10) after treatment was compared in the two groups. Gastric metaplasia declined in eradicators from 16% to 8% (p < 0.05) while in non-eradicators there was no significant change (25% initially and at follow up). A positive relation between extent of gastric metaplasia and duodenal inflammation score was present before treatment (r(s) = 0.74, p < 0.001) and was unchanged after treatment in the non-eradicator group (r(s) = 0.89, p < 0.001). In the eradicator group, however, the inflammation score had significantly declined (p < 0.02) and the close relation with gastric metaplasia was no longer present. These results suggest that H pylori itself is at least in part responsible for producing gastric metaplasia of the duodenum.     

Effect of Helicobacter pylori eradication on bulbitis and duodenal gastric metaplasia

BACKGROUND/AIMS: Duodenal gastric metaplasia seems to be linked to infection by Helicobacter pylori, to the extent of acid secretion and to bulbitis. An investigation was made of the relationship between bulbitis and duodenal gastric metaplasia, or whether bulbitis can arise along with duodenal gastric metaplasia after Helicobacter pylori eradication in an average of six years. METHODOLOGY: We compared 22 patients with duodenal ulcers [male/female 16/6; (mean age+/-SD) 55+/-12 years] Helicobacter pylori-negative after eradication, with 23 Helicobacter pylori-positive patients free from active duodenal ulcers [male/female 17/6; (mean age+/-SD) 59+/-12 years]. RESULTS: The bulbitis score was found to be lower in the Helicobacter pylori-negative than in the Helicobacter pylori-positive group (p=0.02). The duodenal gastric metaplasia score in the Helicobacter pylori-negative was higher than in the Helicobacter pylori-positive group (p=0.001). We failed to find any relationship between the presence of bulbitis and duodenal gastric metaplasia. We found a non-significant inverse correlation between the presence of duodenal gastric metaplasia and chronic body gastritis (p=0.07). CONCLUSIONS: Bulbitis and duodenal gastric metaplasia may depend on different causal factors not related to Helicobacter pylori infection. The extension of duodenal gastric metaplasia with time following recovery from peptic ulcer disease may represent a mucosal protection factor against acid.     

Effect of Helicobacter pylori eradication on malignant transformation of gastric adenoma

BACKGROUND: A nonrandomized trial of Helicobacter pylori eradication was conducted in patients with endoscopically diagnosed gastric adenoma to determine the long-term effect of antimicrobial treatment on progression of the adenoma. METHODS: Of 64 patients with an endoscopically diagnosed gastric adenoma and H pylori infection, 32 were treated with omeprazole and antibiotics to eradicate the infection, and 32 were not. RESULTS: During 2 years of follow-up, 4 (12.5%) of the 32 patients in the untreated group developed an early stage, intestinal-type gastric cancer, whereas no gastric cancer was found in the 32 patients in the treated group. CONCLUSION: H Pylori eradication may inhibit progression of gastric adenoma to carcinoma.     

Helicobacter pylori eradication: Exploring its impacts on the gastric mucosa

Helicobacter pylori (H. pylori) infects approximately 50% of all humans globally. Persistent H. pylori infection causes multiple gastric and extragastric diseases, indicating the importance of early diagnosis and timely treatment. H. pylori eradication produces dramatic changes in the gastric mucosa, resulting in restored function. Consequently, to better understand the importance of H. pylori eradication and clarify the subsequent recovery of gastric mucosal functions after eradication, we summarize histological, endoscopic, and gastric microbiota changes to assess the therapeutic effects on the gastric mucosa.     

Enhanced somatostatin secretion into the gastric juice with recovery of basal acid output after Helicobacter pylori eradication in gastric ulcers

BACKGROUND AND AIM: Antral somatostatin interacts with gastric acid secretion. We aimed to investigate the effect of eradication on gastric acid, somatostatin secretion and mucosal histology in gastric ulcer patients with Helicobacter pylori (H. pylori) infection. METHODS: Twenty-eight patients (21 male, 7 female) with H. pylori-positive gastric ulcer were treated with dual therapy. Before and 4-8 weeks after the therapy, the histology of biopsy specimens, basal acid output (BAO) and maximal acid output (MAO) after stimulation with tetragastrin were assessed. Somatostatin concentration in the gastric juice was measured by radioimmunoassay, and somatostatin output during either the basal or gastrin-stimulated period was also examined. RESULTS: Eradication was successful in 22 patients. Before treatment, the acid and somatostatin output were inversely related to the severity of neutrophil infiltration in the corpus and antrum, respectively. After successful eradication, improvement of histological inflammation and an increase in BAO, basal and gastrin-stimulated somatostatin output were observed. Eradication had no effect on atrophy and MAO. There was a positive correlation between gastric acid and somatostatin output in the basal or stimulated condition, irrespective of H. pylori infection. CONCLUSIONS: The present results suggest that recovery of gastric BAO may be caused by an improvement in corpus neutrophil infiltration, but not by an increase in parietal cell volume or a change in atrophy. Also, there was an increase in basal and gastrin-stimulated somatostatin-containing cell activity accompanied by improved antral neutrophil infiltration in the early phase after H. pylori eradication in gastric ulcers.     

Effect of Helicobacter pylorieradication on gastric hyperplastic polyposis in Cowden＇s disease

A 21-year-old woman with complaints of hematochezia was diagnosed as having Cowden's disease (CD), an autosomal dominant condition characterized by multiple hamartomas, since facial papules and gingival papillomas were identified. On endoscopy, multiple hyperplastic polyps were seen in the rectum and left-side colon. There were also esophageal glycogenic acanthosis and hyperplastic polyposis in the antrum accompanied by Helicobacter pylori-related gastritis. Although gastric hyperplastic polyposis had by no means regressed with unsuccessful first-line eradication therapy for H pylori, following cure of the infection with salvage therapy consisting of rabeprazole, amoxicillin and metronidazole, the polyposis lesions almost disappeared. Follow-up gastroscopy 2 and 3 years after cessation of the second-line eradication therapy revealed almost complete regression of the polyposis lesions with no evidence of H pylori infection. We recommend eradication treatment for CD patients with gastric hyperplastic polyps and the infection, as the occurrence of gastric carcinoma among hyperplastic polyps has been described.     

Helicobacter pylori eradication for preventing gastric cancer

Helicobacter pylori(H.pylori)infection is a major riskfactor for gastric cancer(GC)development,which isone of the most challenging malignant diseases worldwide with limited treatments.In the multistep pathogenesis of GC,H.pylori infection slowly induces chronicactive gastritis,which progresses through the premalignant stages of atrophic gastritis,intestinal metaplasia,and dysplasia,and then finally to GC.Although eradication of H.pylori is a reasonable approach for the prevention of GC,there have been some contradictory reports,with only some long-term follow-up data showingefficacy of this approach.The inconsistencies are likely due to the insufficient number of participants,relatively short follow-up periods,poor quality of study designs,and the degree and extent of preneoplastic changes atthe time of H.pylori eradication.This review analyzesrecent high-quality studies to resolve the discrepancies regarding the eradication of H.pylori for GC prevention.The relationship between H.pylori eradication and GC/precancerous lesions/metachronous GC is examined,and the cost-effectiveness of this strategy in the prevention of GC is assessed.Although it is assumed that eradication of H.pylori has the potential to prevent GC,the feasibility and appropriate timing of this strategy for cancer prevention remain to be determined.As a result,additional well-designed trials with longer followup periods are needed to clarify this issue.     

Chemoprevention of gastric cancer by Helicobacter pylori eradication and its underlying mechanism

The cascade of gastric cancer, a leading cause of cancer incidence and mortality, is multifactorial. Helicobacter pylori (HP) infection plays a major role in gastric cancer (GC), and there has been an accumulation of data regarding the chemopreventive effect of HP eradication. However, it remains unclear how HP infection causes GC and how HP eradication prevents GC. To clarify this issue, the following approaches were performed in this review article. First, how HP‐induced atrophic gastritis (AG) and intestinal metaplasia (IM) provoke the development of GC is shown, followed by how long HP eradication takes to induce a reversible change in AG and IM. Second, epigenetic studies of PTPN6, MOS, DCC, CRK, and VAV1 were performed in noncancerous gastric specimens in terms of HP status. Among these genes, MOS was found to be a possible surrogate marker for GC development. HP eradication decreased aberrant DNA methylation in a gene‐specific manner, and MOS played a role in metachronous gastric neoplasms. Third, transforming growth factor‐β1 (TGF‐β1) and TGF‐β1‐induced epithelial‐mesenchymal transition (EMT) markers were investigated in gastric mucosa. HP infection triggered the TGF‐β1‐induced EMT pathway and caused the emergence of GC stem cells, such as CD44v8‐10. When HP was eradicated, these two pathways were inhibited. Finally, a 2222 cohort study showed that HP eradication significantly decreased the risk of noncardiac GC. Taken together, HP eradication is effective as a primary GC prevention method, and its underlying mechanism includes reversibility of AG and IM, methylation, EMT, and stem cells.     

Gastric juice ascorbic acid is related to Helicobacter pylori infection but not ethnicity

BACKGROUND: Maori and Pacific Island ethnic groups in New Zealand have a high risk for gastric cancer. Low levels of gastric juice ascorbic acid (vitamin C) have been suggested to be a risk factor for gastric cancer. Previous studies have shown that gastric juice ascorbic acid may be independently associated with both ethnicity and Helicobacter pylori infection. This study aimed to examine the interrelationship between H. pylori and ethnicity in New Zealand. METHODS: Gastric juice was collected into 70% perchloric acid preservative and stored at -80 degrees C. Ascorbic acid was analysed by high-performance liquid chromatography using ion-pair chromatography and electrochemical detection. Inflammation and atrophy was graded from biopsies from multiple sites in the antrum and body. Gastric juice was collected from 89 patients during routine endoscopy. RESULTS: There was a wide range of measured gastric juice ascorbic acid from 0.001 to 410 microg/mL. The median concentration of ascorbic acid for H. pylori-negative patients was 1.78 microg/mL (n = 57) and 0.12 microg/mL (n = 32) for H. pylori-positive patients (P = 0.001). Gastric juice ascorbic acid concentration was not associated with age, endoscopic diagnosis or intestinal metaplasia, but was significantly associated with the degree of acute inflammation (P = 0.01) and the presence of atrophy (P = 0.04).The median ascorbic acid concentration for European patients was 0.92 microg/mL (n = 44) and 0.09 microg/mL (n = 38) for Maori and Pacific Island ethnic groups combined (P = 0.1). Multiple step-wise regression analysis showed that only H. pylori infection was a significant factor for predicting ascorbic acid concentrations (r2 = 0.12). CONCLUSIONS: This study has confirmed that gastric juice ascorbic acid concentration is lower in the presence of H. pylori infection.     

Prevention of gastric cancer by Helicobacter pylori eradication

The evidence supporting the important role of Helicobacter pylori causing gastric cancer is getting stronger. The mechanisms by which H. pylori can influence the progression to severe changes in the gastric mucosa are under investigation. An increased gastric epithelial cell proliferation has been observed in individuals infected with H. pylori. This lifelong increased cell turnover is deemed to be a major risk factor for increased mutational changes and may lead to the development of gastric cancer. Successful eradication of H. pylori infection induces the healing of the gastritis and a significant decrease in gastric epithelial cell proliferation. Nevertheless, it is right now unknown at which time the point of no return, meaning at which time an eradication therapy leads to a benefit for the individual to prevent gastric cancer, has been reached. Therefore the major question that arises is to whom an eradication therapy should be offered to prevent gastric cancer. A general elimination of the infection might be worthwhile, but seems to be unrealistic now because of the high prevalence of the infection and the missing of a vaccine. This review reflects possible mechanisms of gastric cancer development induced by chronic H. pylori infection and recent investigational trials for prevention of gastric cancer by H. pylori eradication therapy will be discussed.     

Acute Helicobacter pylori infection: clinical features, local and systemic immune response, gastric mucosal histology, and gastric juice ascorbic acid concentrations.

The symptomatology of a case of acute infection with Helicobacter pylori is described, together with the accompanying changes in gastric mucosal histology, local and systemic humoral immune response, and gastric ascorbic acid concentration. The patient was an endoscopist, previously negative for the carbon-14 urea breath test, who had a week of epigastric pain and then became asymptomatic. H pylori was detected by culture of antral biopsy specimens and was still present after 74 days. Five days after infection the histological findings showed acute neutrophilic gastritis; by day 74 changes of chronic gastritis were evident. The patient seroconverted by IgG enzyme linked immunosorbent assay by day 74, but a mucosal IgM and IgA response was evident as early as day 14. Infection was accompanied by a transient hypochlorhydria but a sustained fall in gastric juice ascorbic acid concentration.     

Metachronous gastric cancer after successful Helicobacter pylori eradication

The high incidence of gastric cancer in Japan initially resulted in establishment of a country-wide gastric cancer screening program to detect early and treatable cancers. In 2013 countrywide Helicobacter pylori (H. pylori) eradication was approved coupled with endoscopy to assess for the presence of chronic gastritis. Current data support the notion that cure of the infection in those with non-atrophic gastritis will prevent development of gastric cancer. However, while progression to more severe damage is halted in those who have already developed, atrophic gastritis/gastric atrophy remain at risk for subsequent development of gastric cancer. That risk is directly related to the extent and severity of atrophic gastritis. Methods to stratify cancer risk include those based on endoscopic assessment of the atrophic border, histologic grading, and non-invasive methods based on serologic testing of pepsinogen levels. Continued surveillance is required because those with atrophic gastritis/gastric atrophy retain considerable gastric cancer risk even after H. pylori eradication. Those who have already experienced a resectable early gastric cancer are among those at highest risk as metachronous lesions are frequent even after H. pylori eradication. We review the role of H. pylori and effect of H. pylori eradication indicating the incidence and the predictive factors on development of metachronous cancer after endoscopic therapy of early gastric cancer. Studies to refine risk markers to stratify for risk, surveillance methods, intervals, and duration after successful H. pylori eradication, and whether adjuvant therapy would change risk are needed.     

Helicobacter pylori of the remnant stomach and its eradication.

BACKGROUND/AIMS: Many authors have reported that Helicobacter pylori (H. pylori) is one of the major causes of gastritis and peptic ulcer. This study was conducted to evaluate the incidence of H. pylori infection and the curative effects of amoxicillin and omeprazole on H. pylori in the remnant stomach. METHODOLOGY: Biopsy specimens were obtained from 70 patients who underwent gastrectomy for gastric cancer. H. pylori was subsequently diagnosed by CLO test and culture of H. pylori. Gastritis was assessed by the scoring of four characteristic pathological parameters. Patients with positive H. pylori were eligible for the eradication study. Amoxicillin, 750 mg per day for 2 weeks, and omeprazole, 20 mg per day for 8 weeks, were administered to them. Endoscopic reexamination was performed 12 weeks after the initiation of treatment. RESULTS: The overall positive rate of H. pylori was 37.1%; 39.6% in Billroth I reconstruction, 0% in Billroth II reconstruction, and 55.6% in pylorus preserving gastrectomy, respectively. The positive H. pylori rate of Billroth II reconstruction was significantly low. However, there was no association of positive rate of H. pylori with time. There was no significant difference of gastritis scores between H. pylori infected patients and non-infected patients. The eradication rate was 70.0%. CONCLUSIONS: H. pylori was present in 37.1% of patients who underwent gastrectomy. Gastritis was not significantly severe in H. pylori infected patients. The treatment with amoxicillin and omeprazole was effective for these patients.     

Healing of Helicobacter pylori gastric ulcers: only eradication matters.

INTRODUCTION: some authors suggest that Helicobacter pylori eradication favors gastric ulcer healing. OBJECTIVE: to study which factors influence ulcer healing in patients suffering from gastric ulcer with H. pylori infection. SUBJECTS AND METHODS: a prospective study of 230 patients with gastric ulcer associated to H. pylori infection. Chronic ingestion of non-steroidal anti-inflammatory drugs was considered as an exclusion. In an initial endoscopy, malignancy was histologically excluded and two biopsies each of antrum and body were obtained. Also, ELISA IgG serology and a 13C-urea breath test were performed. Eradication therapy with omeprazole (20 mg twice a day), clarithromycin (500 mg twice a day) and amoxicillin (1 g twice a day) was administered for seven days, followed by omeprazole 20 mg once a day for five more weeks. Endoscopy was repeated after 6 weeks of treatment and breath test was repeated 2 month after completing therapy. RESULTS: overall gastric ulcer healing was achieved in 80.8% (95% CI: 75-85%) of cases by intention-to-treat, and in 82.6% (77-87%) per protocol. Ulcer healing was achieved in 94.3% (90-97%) of patients with eradication success, but only in 40.8% (28-54%) of patients with eradication failure (p<0.0001). In the multivariate analysis, H. pylori eradication was the only variable that correlated with ulcer healing (odds ratio 24; 95% CI: 10-56; p<0.0001) (x2 model: 64.4; p<0.0001). Additional variables (age, sex, sporadic ingestion of NSAIDs, smoking, previous ulcer disease, ulcer size and location) were not related to healing. CONCLUSION: H. pylori eradication favors ulcer healing in patients with gastric ulcer, which is an argument in favor of the etiological role of the microorganism in this disease. Other factors did not influence ulcer healing.     

Effect of Helicobacter pylori eradication on gastroesophageal function

BACKGROUND: To elucidate the cause of possible occurrence of reflux esophagitis after Helicobacter pylori eradication, gastric and esophageal function among H. pylori infected Japanese patients were evaluated both before and after eradication therapy. METHODS: Nine H. pylori-positive patients were studied before and 6 months after successful H. pylori eradication. Studies included gastric emptying, esophageal manometry, gastric and esophageal pH monitoring as well as measuring serum levels of gastrin, pepsinogen I and pepsinogen II. RESULTS: Helicobacter pylori eradication was associated with a significant change in serum gastrin and pepsinogen levels, consistent with the improvement in mucosal inflammation. There was no significant change in gastric emptying, fasting or postprandial lower esophageal sphincter (LES) pressure, esophageal primary peristaltic contractions, frequency of transient LES relaxation, or gastroesophageal reflux, as assessed by 24 h pH monitoring. The percent time of the gastric pH>4 at night decreased significantly. A 41-year-old male developed erosive gastroesophageal reflux disease (GERD) (Los Angeles Classification Grade A) after eradication. Physiological studies showed he had abnormal esophageal motility prior to H. pylori eradication. CONCLUSIONS: With the exception of gastric pH at night, most patients did not experience a significant change in gastric or esophageal function after H. pylori eradication. Development of GERD post H. pylori eradication likely reflects an increase in the acidity of the refluxate superimposed on pre-existing abnormalities in gastroesophageal motility.