Clinicopathological analysis of early-stage gastric cancers detected after successful eradication of Helicobacter pylori

Background and Aims: The results of a randomized controlled study and meta‐analysis study have recently proved that Helicobacter pylori eradication has a preventive effect against the development of metachronous and primary gastric cancer. However, gastric cancer is sometimes detected after successful eradication. There is a lack of study about gastric cancers in eradicated patients. To clarify the characteristics of gastric cancers detected after H. pylori eradication, we analyzed the clinicopathological features of these cancers. Methods: The subjects were 18 early‐stage gastric cancer specimens resected from 17 patients who had received successful eradication of H. pylori from February 1995 to March 2009. The control group consisted of 36 specimens from noneradicated patients with persistent H. pylori infection who were matched with the subjects in age, sex, and depth of invasion. Clinicopathological features and mucin phenotypes of gastric cancer were clinically and immunohistologically evaluated. Results: The average diameter of gastric cancer was smaller and Ki‐67 index was lower in the eradication group. The morphological distribution of depression types was significantly lower in the control group. Immunohistochemical phenotyping revealed that 72.2% of the lesions in the eradicated group were complete gastric type or gastric predominant mixed type, whereas the percentages of gastric type and intestinal type in the control group were similar. Conclusion: Our findings indicate that the clinicopathological characteristics of gastric cancers detected after H. pylori eradication are different from those of gastric cancers in patients with persistent H. pylori infection. H. pylori eradication may suppress intestinalization during the development of gastric cancer.     

Previous Helicobacter pylori infection–induced atrophic gastritis: A distinct disease entity in an understudied population without a history of eradication

Individuals with chronic atrophic gastritis who are negative for active H. pylori infection with no history of eradication therapy have been identified in clinical practice. By excluding false‐negative and autoimmune gastritis cases, it can be surmised that most of these patients have experienced unintentional eradication of H. pylori after antibiotic treatment for other infectious disease, unreported successful eradication, or H. pylori that spontaneously disappeared. These patients are considered to have previous H. pylori infection–induced atrophic gastritis. In this work, we define these cases based on the following criteria: absence of previous H. pylori eradication; atrophic changes on endoscopy or histologic confirmation of glandular atrophy; negative for a current H. pylori infection diagnosed in the absence of proton‐pump inhibitors or antibiotics; and absence of localized corpus atrophy, positivity for autoantibodies, or characteristic histologic findings suggestive of autoimmune gastritis. The risk of developing gastric cancer depends on the atrophic grade. The reported rate of developing gastric cancer is 0.31%‐0.62% per year for successfully eradicated severely atrophic cases (pathophysiologically equal to unintentionally eradicated cases and unreported eradicated cases), and 0.53%‐0.87% per year for spontaneously resolved cases due to severe atrophy. Therefore, for previous H. pylori infection–induced atrophic gastritis cases, we recommend endoscopic surveillance every 3 years for high‐risk patients, including those with endoscopically severe atrophy or intestinal metaplasia. Because of the difficulty involved in the endoscopic diagnosis of gastric cancer in cases of previous infection, appropriate monitoring of the high‐risk subgroup of this understudied population is especially important.     

Clinical application of 20 MHz endosonography and anti-Helicobacter pylori immunoblots to predict regression of low-grade gastric MALToma by H. pylori eradication

Aim. We tested whether serial 20 MHz endosonography (EUS) and anti‐Helicobacter pylori immunoblots can predict the complete regression of gastric MALToma by H. pylori eradication. Methods. The serums of 17 MALToma patients, including 15 with low grade and two with high grade, were collected before therapy. Fifteen patients with low‐grade MALToma and 18 nonMALToma patients, all infected with H. pylori, have been followed with serum sampling, endoscopy, and EUS on enrollment, on the 2nd, 6th, and 12th months after anti‐H. pylori therapy. All sera were tested for anti‐H. pylori immunoblots, including 19.5, 26.5, 30, 35, 89, 116 KDa (CagA), FldA. The DNAs were extracted serially from the biopsy of MALToma patients before and after therapy to perform polymerase chain reaction (PCR) for the immunoglobulin heavy‐chain gene monoclonality. Results. MALToma patients had higher prevalence rates of anti‐FldA protein, 19.5 and 30 KDa antibodies of H. pylori (p < 0.01). After H. pylori eradication, MALToma patients had negative seroconversion of 19.5, 26.5, 30, and 35 KDa antibodies (p < 0.05), but not in CagA and FldA. The PCR monoclonality occurred in 80% (12/15) of the MALToma patients before therapy, but did not correlate with any seroconversion of anti‐H. pylori immunoblots after therapy (p > 0.05). Complete regression of MALToma was observed in 73.3% (11/15) of patients. Evaluation with 20 MHz EUS, for the initial tumor depth and its normalization on the 6th month had 90.9% sensitivity and 100% specificity to predict the complete regression. Discussion. The negative seroconversions of the smaller‐molecular‐weight proteins, but not CagA and FldA, correlate with regression of MALToma by H. pylori eradication. 20 MHz EUS can effectively predict the therapeutic response of MALToma.     

Helicobacter pylori associated antigastric autoantibodies: role in Sjögren's syndrome gastritis

Background. Previous studies have shown that Helicobacter pylori seroprevalence in Sjögren's syndrome is comparable with that of the general population. However, the origin of the chronic gastropathy associated with this syndrome and the role of local autoimmunity – possibly triggered by bacterial infection – in its pathogenesis remain unclear. Materials and Methods. We initially determined the prevalence of IgG anti H. pylori in dyspeptic subjects with and without Sjögren's syndrome. In subsets of both groups we then determined anti CagA and human tissue‐tested anticanalicular/antifoveolar autoantibodies. We also compared activity, atrophy and Mucosa Associated Lymphoid Tissue (MALT) scores, as well as symptoms, before and after bacterial eradication. Results. Prevalence of H. pylori in Sjögren's syndrome patients was similar to controls: 31/54 (57%) vs. 93/150 (62%). Anti CagA prevalence was also similar in the two groups. Twenty weeks after H. pylori eradication, histological activity decreased in both groups, however, atrophy and MALT decreased significantly only in controls. Sixteen months after H. pylori eradication, 75% of Sjögren's syndrome patients still complained of dyspepsia compared with 13% of controls. Finally, antigastric autoantibodies were present in 29% of tested Sjögren's syndrome patients vs. 28% of controls. Conclusions. H. pylori infection was equally prevalent among dyspeptic Sjögren's syndrome patients and dyspeptic controls. Likewise, there were no differences regarding anti CagA prevalence or antigastric autoantibodies among the two groups. The persistence of symptoms as well as of the lymphocytic infiltration and atrophy after H. pylori eradication in Sjögren's syndrome may underlie the ‘endogenous’ and still unknown nature of the gastropathy in this condition.     

Interactions Among Gastric Somatostatin, Interleukin-8 and Mucosal Inflammation in Helicobacter pylori-Positive Peptic Ulcer Patients

Background. To investigate whether Helicobacter pylori infection, but not drugs, affects gastric somatostatin, interleukin‐8 (IL‐8), histological inflammation through eradication therapy, and interactions among these parameters. Methods. Twenty‐eight H. pylori‐positive patients (21 males; mean age 47.0 years) with either gastric ulcer (GU: n = 11) or duodenal ulcer (n = 17) diagnosed endoscopically were treated with dual therapy. Eradication was defined as negative microbiologic tests and ¹³C‐urea breath test. Levels of antral and gastric juice somatostatin and mucosal IL‐8 were measured by radioimmunoassay and enzyme‐linked immunosorbent assay, respectively. Histology was assessed by the Sydney system. Results. H. pylori was eradicated in 15 patients (10 males, 6 GU) out of 28 (54%). The patients’ backgrounds did not affect the eradication of H. pylori. Successes in eradication significantly increased antral and juice somatostatin contents, and dramatically decreased IL‐8 levels and histological gastritis. In contrast, persistent H. pylori infection did not affect somatostatin and histological gastritis. An inverse correlation was present between changes in somatostatin levels and histological activity. No relationship was observed in changed values between antral somatostatin and IL‐8. Conclusions. These results indicate that eradication of H. pylori, but not the drugs used, induced an increase in somatostatin levels in the antrum and gastric juice, suggesting a close relationship between H. pylori and gastric somatostatin regulation. A close correlation between an increase in gastric somatostatin levels and the normalization of histological activity was present, suggesting that certain peptide‐immune interactions in the gastric mucosa exist in H. pylori infection.     

Stool antigen assay to screen H. pylori infection and to assess the success of 3-Day and 7-Day eradication therapy in the patients with partial gastrectomy

Background. Even after partial gastrectomy, Helicobacter pylori may persist in the residual stomach but be less abundant in the bacterial load. H. pylori stool antigen is a reliable noninvasive tool to detect H. pylori infection in patients without gastrectomy. We thus test whether [ 1 ] the course of H. pylori eradication therapy could be diminished [ 2 ]; stool antigen can effectively detect H. pylori infection for the patients with gastrectomy. Methods. One hundred and eight patients who had undergone partial gastrectomy were enrolled to receive panendoscopy and provided stool samples for H. pylori stool antigen within 3 days after endoscopy. The H. pylori‐infected patients were then randomized to receive either a 3‐ or 7‐day triple therapy for H. pylori eradication. Six weeks later, to evaluate the success of H. pylori eradication, patients received a follow‐up endoscopy and again provided stool samples for H. pylori stool antigen. Results. Seventy out of 108 patients, proven to have H. pylori infection, were evenly randomized into 3‐day and 7‐day therapy groups. The H. pylori eradication rates were similar between the 3‐day and 7‐day triple therapy (90.9 vs. 93.8%, p > .05). Before therapy, the H. pylori stool antigen was 93% sensitive and 100% specific to detect H. pylori. After therapy, H. pylori stool antigen remain 100% sensitive and 88.3% specific to detect the failure of eradication therapy. Conclusion. H. pylori stool antigen is a highly reliable tool to screen H. pylori infection before therapy and to assess the success of eradication therapy in partial gastrectomy patients. To eradicate H. pylori infection for patients with partial gastrectomy, the duration of triple therapy can be shortened.     

Antral nodularity and positive CagA serology are distinct and relevant markers of severe gastric inflammation in children with Helicobacter pylori infection

Background. The aim of this study was to assess whether the endoscopic finding of antral nodularity and serum IgG antibodies to CagA are associated with higher grades of gastric inflammation. Materials and methods. The comprehensive data of two previously published trials were reanalysed. One hundred and fifty‐three children (median age 9.5 years) who underwent gastroscopy were included. Biopsy specimens from the antrum and corpus were taken to assess Helicobacter pylori status, gastritis score and lymphoid follicles. During endoscopy, antral nodularity was noted. Serum samples were assayed for IgG antibodies to CagA. Results. The presence of antral nodularity (nod+) and positive CagA serology (CagA+) were each found in 32 of the 77 (41.5%) children who had evidence of H. pylori infection. Crosstabulation showed that 20 children (26%) were nod+/CagA+, 12 (15.5%) nod+/CagA?, 12 (15.5%) nod‐/CagA+ and 33 (43%) nod?/CagA?. Gastritis score was significantly lower in nod?/CagA?children than in nod+/CagA? (p = .004), nod?/CagA+ (p = .002) and nod+/CagA+ (p < .001), both in the antrum and corpus. Completely normal gastric histology was only found in the nod?/CagA?subgroup of H. pylori‐infected children (eight of 33, 24%). Regression analysis showed that antral nodularity and positive CagA serology were related to severe gastric inflammation independently of each other and age. Separate analysis showed that inflammation (p < .001), activity (p < .001) and H. pylori density (p = .002) scores were significantly lower in nod?/CagA?children compared with nod+/CagA+ children. The number of lymphoid follicles in the gastric mucosa was related to antral nodularity (p = .003) and positive CagA serology (p = .043), independently of each other. Conclusions. Antral nodularity and positive CagA serology are distinct and relevant markers of severe gastric inflammation in children with H. pylori infection. The lack of both findings in the same child reflects low‐grade or no gastritis.     

Effects of Helicobacter pylori eradication on gastroesophageal reflux disease

Background and Aims: Helicobacter pylori infection appears to be a protective factor for gastroesophageal reflux disease (GERD). However, H. pylori is associated with the subtype of esophageal carcinoma, and long‐term proton‐pump inhibition usage would cause gastric atrophy in patients with persistent H. pylori infection, which is a precancerous lesion. The relationship between H. pylori infection and GERD is still unclear. We aimed to confirm whether the eradication of H. pylori would worsen or improve symptomatic or endoscopic GERD. Methods: A systematic review of the published data was undertaken, and a meta‐analysis was performed to determine the effect of H. pylori eradication on the occurrence of symptomatic (heartburn, acid regurgitation) and endoscopically proven erosive (esophagitis) GERD in patients with or without pre‐existing GERD. Results: A total of 11 articles met the inclusion criteria and thus were included in the meta‐analysis. There was no significant difference in the frequency of symptomatic or endoscopically proven erosive GERD after the eradication between patients with H. pylori eradicated and those with persistent infection, regardless of follow‐up period, location, or the baseline disease. Conclusion: H. pylori eradication does not aggravate the clinical outcomes in terms of short‐term and long‐term posteradication occurrence of GERD. There is no association between H. pylori eradication and the development of GERD in the patients with different diseases, even those with GERD.     

Efficacy and safety of faropenem in eradication therapy of Helicobacter pylori

Aims: While triple therapy with a proton pump inhibitor, amoxicillin, and clarithromycin is the standard therapy for Helicobacter pylori eradication, it is ineffective against clarithromycin‐resistant strains. To seek a better regimen for eradication therapy, we assessed the sensitivity of clinical strains seen in Japan to faropenem and then evaluated the efficacy and safety of eradication therapy containing this antibiotic. Methods: Minimum inhibitory concentrations (MICs) of faropenem were determined in 78 Japanese clinical H. pylori isolates using the agar dilution method. H. pylori‐positive patients were consecutively assigned to a 7‐day eradication therapy protocol with LAF (lansoprazole 60 mg/day, amoxicillin 2000 mg/day, and faropenem 600 mg/day), and then to a 14‐day protocol. The outcomes of the therapies were assessed by ¹³C‐urea breath tests. Results: All 78 strains showed MICs of faropenem that were equal to or less than 0.2 µg/mL. The eradication rates according to intention‐to‐treat analyses were 46.5% with the 7‐day therapy (n = 43) and 62.5% with the 14‐day therapy (n = 32). No special measures were required to treat the adverse events observed in approximately one‐third of the patients. Conclusions: Faropenem was found to have good antimicrobial action against H. pylori in vitro. The 14‐day LAF therapy successfully eradicated H. pylori in about two‐thirds of the patients although the incidence of adverse events was high.     

Is the recurrence of Helicobacter pylori infection after eradication therapy resultant from recrudescence or reinfection,in Japan

Background. Reinfection of Helicobacter pylori after eradication is rare in developed countries but most often occurs within 1 year. In the present study, we attempted to differentiate between reinfection and recrudescence of H. pylori strains between 6 months and 6 years after successful eradication in Japan, a country with a high prevalence of H. pylori infection. Materials and Methods. After successful eradication of H. pylori, 274 patients were followed up by endoscopy and urea breath test. In recurrent patients, H. pylori strains isolated initially and after recurrence were compared using PCR‐based restriction fragment length polymorphism (RFLP) analysis. Results. Recurrence of H. pylori occurred in 15 of 274 patients (5.5%) at 6 months after eradication and the annual recurrence rate was 2.0% per patient year (between 1 and 6 years). PCR‐based RFLP analysis of H. pylori strains isolated initially and after recurrence showed that 62.5% (at 6 months) and 100% (after 1 years) of bacteria were of different strains. Conclusion. Reinfection of H. pylori was not as rare at 6 months after eradication as reported previously, and up to 6 years after eradication, the annual reinfection rate is 2.0% per patient year in Japan.     

Helicobacter pylori-negative gastric cancer in South Korea: incidence and clinicopathologic characteristics

Background and Aim: It is difficult to determine the exact incidence rate of Helicobacter pylori (H. pylori) infection‐negative gastric cancer (HPIN‐GC) because H. pylori detection rates decrease with the progression of gastric atrophy and intestinal metaplasia. The aim of this study was to evaluate the incidence and clinicopathologic characteristics of HPIN‐GC in South Korea. Methods: Helicobacter pylori infection status was evaluated by histology, a rapid urease test (CLO test), culturing, serology, and history of H. pylori eradication for 627 patients with gastric cancer. Current H. pylori infection was defined as positive results from histology, the CLO test, and culturing. Previous H. pylori infection was defined as negative in all three biopsy‐based tests and positive serology or history of H. pylori eradication. Patients were considered to be negative for H. pylori infection if all results from five methods were negative. However, patients who were found to have severe gastric atrophy by the serum pepsinogen test or metaplastic gastric atrophy by histology were assumed to have had a previous H. pylori infection even if results from other tests for H. pylori infection were all negative. Results: The number of patients with gastric cancer with current or previous H. pylori infection was 439 (70.0%) and 154 (24.6%), respectively. The rate of HPIN‐GC occurrence was 5.4% (n = 34). Sex, age, Lauren type, location of the tumor, and treatment modalities were not different according to H. pylori infection status. However, HPIN‐GC had a more advanced pT classification (T3/T4; 51.9 vs 31.1%, p = .025) and a more advanced stage (more than stage I; 63 vs 41.3%, p = .027) than H. pylori‐positive gastric cancer. Conclusion: At least 5.4% cases of gastric cancer were H. pylori negative among South Korean patients. HPIN‐GC looks like to have a poorer prognosis than H. pylori‐positive cases.     

CagA tyrosine phosphorylation in gastric epithelial cells caused by Helicobacter pylori in patients with gastric adenocarcinoma

Background. Tyrosine phosphorylation of Helicobacter pylori cytotoxin‐associated protein of in gastric epithelial cells is reported. The goals of this study are first to examine the occurrence of CagA tyrosine phosphorylation in H. pylori strains isolated from patients with gastric adenocarcinoma and gastritis, and second to clarify the relationship between the diversity of tyrosine phosphorylation motifs and the presence of CagA tyrosine phosphorylation. Methods. Fifty‐eight clinical isolates of H. pylori from patients with gastric adenocarcinoma (29 cases) and gastritis (29 cases) were studied for CagA tyrosine phosphorylation by Western blotting. Sequence diversity of tyrosine phosphorylation motifs was analysed among positive‐ or negative‐CagA tyrosine phosphorylation isolates. Results. Positive CagA tyrosine phosphorylation was found in 93.1% (27 of 29) of strains from gastric adenocarcinoma patients and 51.7% (15 of 29) of strains from gastritis patients (p < 0.001). Intact motifs were found in H. pylori isolates with CagA tyrosine phosphorylation. Of the 16 negative CagA tyrosine phosphorylation isolates, intact tyrosine phosphorylation motifs were found in 15 isolates. Conclusions. CagA tyrosine phosphorylation, which is significantly greater in strains from gastric adenocarcinoma patients, may play a role in gastric carcinogenesis, and could be a better marker of more virulent strains than the cag pathogenicity island in Asia, where the cag pathogenicity island is present in nearly all H. pylori strains. Sequence diversity of tyrosine phosphorylation motifs on CagA was not related to the presence of tyrosine phosphorylation. The absence of tyrosine phosphorylation motif might result in negative tyrosine phosphorylation phenotypes, but such motifs are not the sole factors associated with CagA tyrosine phosphorylation.     

The role of abdominal CT scan as follow-up after complete remission with successful Helicobacter pylori eradication in patients with H. pylori-positive stage I(E1) gastric MALT lymphoma

Background: Eradication of Helicobacter pylori with antibiotics is the established initial treatment of patients with localized gastric mucosa‐associated lymphoid tissue (MALT) lymphoma. However, there are few reports on follow‐up modalities to identify sustained remission in patients who achieve complete remission (CR). We therefore investigated the role of abdominal computed tomography (CT) as follow‐up after CR with H. pylori eradication. Patients and Methods: We retrospectively analyzed 122 patients with H. pylori‐positive stage I_E1 gastric MALT lymphoma who achieved CR with successful H. pylori eradication. Results: The median follow‐up after CR was 35 months (range 3–140months). At a median of 17 months (range 12–21 months) after CR, 7 of 122 patients (5.7%) experienced lymphoma recurrence, all cases of which were confined to the gastric mucosa and were detectable only by endoscopy with multiple biopsies. At the time of recurrence, four of seven patients showed re‐infection by H. pylori. Eradication therapy was successful in these patients, resulting in both bacterial eradication and tumor regression. Three patients who experienced histologic recurrence without H. pylori re‐infection were observed by a watch and wait strategy and again achieved CR. Conclusions: None of the patients with H. pylori‐positive stage I_E1 gastric MALT lymphoma who experienced tumor recurrence after CR with successful H. pylori eradication showed recurrence at extragastric sites, including lymph nodes without gastric mucosal lesion. These findings indicate that endoscopic biopsies without abdominal CT scans are sufficient to detect recurrence in these patients.     

Increased primary resistance to recommended antibiotics negatively affects Helicobacter pylori eradication

Objective. To evaluate the efficacy of two commonly employed treatments for Helicobacter pylori infection and the impact of bacterial resistance to antibiotics on eradication rate. Methods. Ninety‐two consecutive H. pylori‐positive patients with active peptic ulcer disease were randomly enrolled to receive a 7‐day treatment with either lansoprazole 30 mg plus amoxicillin 1 g and clarithromycin 500 mg [all twice a day (b.i.d.), Group A, n = 46]; or bismuth subcitrate 125 mg four times a day (q.i.d.) plus tetracycline 500 mg q.i.d and furazolidone 200 mg b.i.d. (Group B, n = 46) H. pylori status was reassessed 30 days after completion of the therapy and bacterial resistance to the antibiotics was investigated using an in vitro assay. Results. Five patients from each study group were lost to follow up. Both treatments resulted in similar H. pylori eradication rate: 66–60% (per protocol), 59–52% (intention‐to‐treat) in Groups A and B, respectively (non significant). However, eradication improved to 79% in the absence of H. pylori resistance to clarithromycin or amoxicillin. Conclusion. Primary resistance to clarithromycin or amoxicillin may underscore a potentially serious problem for the eradication of H. pylori infection. Testing for bacterial resistance may become necessary to improve therapeutic efficacy.     

Helicobacter pylori and the birth cohort effect: evidence for stabilized colonization rates in childhood

Background: The prevalence of Helicobacter pylori has declined over recent decades in developed countries. The increasing prevalence with age is largely because of a birth cohort effect. We previously observed a decline in H. pylori prevalence in 6‐ to 8‐year‐old Dutch children from 19% in 1978 to 9% in 1993. Knowledge about birth‐cohort‐related H. pylori prevalence is relevant as a predictor for the future incidence of H. pylori‐associated conditions. Aim: The aim of this study was to investigate whether the birth cohort effect of H. pylori observed between 1978 and 1993 continued in subsequent years. Methods: Anti‐H. pylori IgG antibodies and anti‐CagA IgG antibodies were determined in serum samples obtained in 2005/2006 from 545 Dutch children aged 7–9 years who participated in the Prevention and Incidence of Asthma and Mite Allergy birth cohort. The H. pylori and CagA antibodies were determined by enzyme‐linked immunosorbent assays that have been extensively validated in children, with a 94% sensitivity for H. pylori colonization and a 92.5% sensitivity for colonization with a cagA‐positive strain. Results: Of the 545 children (M/F 300/245), most (91.5%) were of Dutch descent. The H. pylori positivity rate was 9% (95% CI 6.6–11.4%). The prevalence of CagA antibodies was 0.9% (95% CI 0.1–1.6%). No significant differences were demonstrated in H. pylori and cagA prevalence in relation to gender or ethnicity. Conclusion: The prevalence of H. pylori in childhood has remained stable in the Netherlands from 1993 to 2005, suggesting a stabilization of the previously decreasing trend in subsequent birth cohorts. This finding may reflect stabilization in determinants such as family size, housing, and hygienic conditions (or offset by day care). If confirmed in other populations in developed countries, it implies that colonization with H. pylori will remain common in the coming decades. Remarkably however, the rate of colonization with cagA⁺H. pylori strains has become very low, consistent with prior observations that cagA⁺ strains are disappearing in Western countries.     

Effect of Helicobacter pylori infection on gastric acid secretion and meal-stimulated serum gastrin in children

Background. Comparative studies of gastric acid secretion in children related to Helicobacter pylori infection are lacking. The purpose of this study was to compare acid secretion and meal‐stimulated gastrin in relation to H. pylori infection among pediatric patients. Materials and Methods. Thirty‐six children aged 10–17 years (17 with H. pylori infection) undergoing diagnostic endoscopy participated in the study. Diagnoses included gastritis only (n = 23), duodenal ulcer (n = 5) and normal histology (n = 8). Gastric acid output was studied using the endoscopic gastric secretion test before and 2–3 months after H. pylori eradication. Meal‐stimulated serum gastrin response was assessed before and 12 months after eradication. Results. H. pylori gastritis was typically antrum‐predominant. Acid secretion was greater in H. pylori‐positive patients with duodenal ulcer than in gastritis‐only patients or controls [mean ± standard error (SE): 6.56 ± 1.4, 3.11 ± 0.4 and 2.65 ± 0.2 mEq/10 minutes, respectively; p < .001]. Stimulated acid secretion was higher in H. pylori‐positive boys than girls (5.0 ± 0.8 vs. 2.51 ± 0.4 mEq/10 minutes, respectively; p < .05). Stimulated acid secretion pre‐ and post‐H. pylori eradication was similar (5.47 ± 0.8 vs. 4.67 ± 0.9 mEq/10 minutes, respectively; p = .21). Increased basal and meal‐stimulated gastrin release reversed following H. pylori eradication (e.g. basal from 134 to 46 pg/ml, p < .001 and peak from 544 to 133 pg/ml, p < .05). Conclusions. H. pylori infection in children is associated with a marked but reversible increase in meal‐stimulated serum gastrin release. Gastric acid hypersecretion in duodenal ulcer remains after H. pylori eradication, suggesting that the host factor plays a critical role in outcome of the infection.     

Eradication of Helicobacter pylori infection reduces the incidence of peptic ulcer disease in patients using nonsteroidal anti-inflammatory drugs: a meta-analysis

Aim: To investigate the association between use of nonsteroidal anti‐inflammatory drugs (NSAID) and Helicobacter pylori infection, interactive effect of H. pylori infection and NSAID use on the development of peptic ulcer disease (PUD), and the effect of H. pylori eradication therapy on PUD development. Material and Methods: We performed a systematic literature search in EMBASE and PubMed for relevant articles published in English between January 1989 and August 2010, with the following MeSH and/or key words: non‐steroidal anti‐inflammatory drugs, or NSAIDs, Helicobacter pylori, or H. pylori, peptic ulcer disease or PUD, and randomized‐control study or clinical trial. The meta‐analysis was conducted using the Review Manager 4.2.2. Results: In the analysis of five studies, the pooled prevalence of H. pylori infection was 74.5% and 71.1% in NSAID users and non‐NSAID users, respectively, (OR = 0.65; 95% CI: 0.35–1.20, p = .170). In the analysis of nine studies, the pooled prevalence of PUD in NSAID users was 31.2% and 17.9% in the presence and absence of H. pylori infection, respectively, (OR = 3.08; 95% CI: 1.26–7.55, p = .010). Moreover, in the analysis of seven studies, PUD developed in 6.4% and 11.8% of NSAID users with and without eradication therapy, respectively (OR = 0.50; 95% CI: 0.36–0.74, p < .001). The preventive effect of the eradication therapy was further revealed in NSAID‐naive users (OR = 0.26; 95% CI: 0.14–0.49, p < .0001) and in the Asian population (OR = 0.30; 95% CI: 0.16–0.56, p < .001). Conclusion: NSAID use is not associated with H. pylori infection in patients with PUD. PUD is more common in H. pylori positive than in negative NSAID users. Moreover, H. pylori eradication therapy reduces PUD incidence in NSAID users, especially in naive users and in the Asian population.     

Helicobacter pylori Eradication in Patients with Immune Thrombocytopenic Purpura: A Review and the Role of Biogeography

Idiopathic thrombocytopenic purpura (ITP) is typically a diagnosis of exclusion, assigned by clinicians after ruling out other identifiable etiologies. Since a report by Gasbarrini et al. in 1998, an accumulating body of evidence has proposed a pathophysiological link between ITP and chronic Helicobacter pylori (H. pylori) infection. Clinical reports have described a spontaneous resolution of ITP symptoms in about 50% of chronic ITP patients following empirical treatment of H. pylori infection, but response appears to be geography dependent. Studies have also documented that ITP patients in East Asian countries are more likely to express positive antibody titers against H. pylori‐specific cytotoxic‐associated gene A (CagA), a virulence factor that is associated with an increased risk for gastric diseases including carcinoma. While a definitive mechanism by which H. pylori may induce thrombocytopenia remains elusive, proposed pathways include molecular mimicry of CagA by host autoantibodies against platelet surface glycoproteins, as well as perturbations in the phagocytic activity of monocytes. Traditional treatments of ITP have been largely empirical, involving the use of immunosuppressive agents and immunoglobulin therapy. However, based on the findings of clinical reports emerging over the past 20 years, health organizations around the world increasingly suggest the detection and eradication of H. pylori as a treatment for ITP. Elucidating the exact molecular mechanisms of platelet activation in H. pylori‐positive ITP patients, while considering biogeographical differences in response rates, could offer insight into how best to use clinical H. pylori eradication to treat ITP, but will require well‐designed studies to confirm the suggested causative relationship between bacterial infection and an autoimmune disease state.     

Systematic review and meta-analysis: Helicobacter pylori eradication therapy after simple closure of perforated duodenal ulcer

Background: The most common complications of peptic ulcer are bleeding and perforation. In many regions, definitive acid reduction surgery has given way to simple closure and Helicobacter pylori eradication. Aim: To perform a systematic review and meta‐analysis to ask whether this change in practice is in fact justified. Materials and Methods: A search on the Cochrane Controlled Trials Register, Medline, and Embase was made for controlled trials of duodenal ulcer perforation patients using simple closure method plus postoperative H. pylori eradication therapy versus simple closure plus antisecretory non‐eradication therapy. The long‐term results for prevention of ulcer recurrence were compared. Results: The pooled incidence of 1‐year ulcer recurrence in H. pylori eradication group was 5.2% [95% confidence interval (CI) of 0.7 and 9.7], which is significantly lower than that of the control group (35.2%) with 95% CI of 0.25 and 0.45. The pooled relative risk was 0.15 with 95% CI of 0.06 and 0.37. Conclusions: Helicobacter pylori eradication after simple closure of duodenal ulcer perforation gives better result than the operation plus antisecretory non‐eradication therapy for prevention of ulcer recurrence. All duodenal ulcer perforation patients should be tested for H. pylori infection, and eradication therapy is required in all infected patients.