Improvement of gastric atrophy after Helicobacter pylori eradication therapy

Cardiovascular and Neurological Diseases and Association with Helicobacter Pylori Infection-An Overview

This article investigates the link between Helicobacter pylori (H. pylori) infection and cardiovascular and neurological disorders. Recent research suggests that H. pylori may play a role in cardiovascular diseases like atherosclerosis, myocardial infarction, and stroke, as well as neurological diseases including Alzheimer's disease, multiple sclerosis, and Parkinson's disease. Cardiovascular Diseases: H. pylori induces endothelial dysfunction and chronic inflammation, promoting atherosclerotic plaque formation and other cardiac complications. High infection prevalence in cardiovascular patients implies that systemic inflammation from H. pylori accelerates disease progression. Eradication therapies combined with anti-inflammatory and lipid-lowering treatments may reduce cardiovascular risk. Neurological Diseases: H. pylori may contribute to Alzheimer's, multiple sclerosis, and Parkinson's through systemic inflammation, neuroinflammation, and autoimmune responses. Increased infection prevalence in these patients suggests bacterial involvement in disease pathogenesis. The eradication of H. pylori could reduce neuroinflammation and improve outcomes. Discussions and Future Research: Managing H. pylori infection in clinical practice could impact public health and treatment approaches. Further research is needed to clarify these relationships. Longitudinal and mechanistic studies are essential to fully understand H. pylori's role in these conditions. Conclusions: H. pylori infection is a potential risk factor for various cardiovascular and neurological conditions. Additional research is critical for developing effective prevention and treatment strategies. Targeted therapies, including H. pylori eradication combined with anti-inflammatory treatments, could improve clinical outcomes. These findings highlight the need for an integrated clinical approach to include H. pylori evaluation and treatment.

Do atrophic gastritis and intestinal metaplasia reverse after Helicobacter pylori eradication?

BACKGROUND

It's still controversial whether Helicobacter pylori (H. pylori) eradication can reverse atrophic gastritis (AG) and intestinal metaplasia (IM). Therefore, we performed a meta-analysis to estimate the effect of H. pylori eradication on AG and IM.

METHODS

We searched the PubMed, Web of Science and EMBASE datasets through April 2023 for epidemiological studies, which provided mean glandular atrophy (GA) or IM score before and after H. pylori eradication, or provided ORs, RRs or HRs and 95% CIs for the association of AG or IM with H. pylori eradication. Weighted mean difference (WMD) and pooled ORs and 95%CIs were used to estimate the effect of H. pylori eradication on AG and IM.

RESULTS

Twenty articles with a total of 5242 participants were included in this meta-analysis. H. pylori eradication significantly decreased GA score in the antrum (WMD -0.36; 95% CI: -0.52, -0.19, p < 0.01), GA score in the corpus (WMD -0.35; 95% CI: -0.52, -0.19, p < 0.01), IM score in the antrum (WMD -0.16; 95% CI: -0.26, -0.07, p < 0.01) and IM score in the corpus (WMD -0.20; 95% CI: -0.37, -0.04, p = 0.01). H. pylori eradication significantly improved AG (pooled OR 2.96; 95% CI: 1.70, 5.14, p < 0.01) and IM (pooled OR 2.41; 95% CI: 1.24, 4.70, p < 0.01). The association remained significant in the subgroup analyses by study design, sites of lesions, regions and follow-up time. Although Publication bias was observed for AG, the association remained significant after trim-and-fill adjustment.

CONCLUSIONS

H. pylori eradication could significantly improve AG and IM at early stage.

Discussion on the common controversies of Helicobacter pylori infection

BACKGROUND

Helicobacter pylori ( H. pylori ) can persistently colonize on the gastric mucosa after infection and cause gastritis, atrophy, metaplasia, and even gastric cancer (GC).

METHODS

Therefore, the detection and eradication of H. pylori are the prerequisite.

RESULTS

Clinically, there are some controversial issues, such as why H. pylori infection is persistent, why it translocases along with the lesser curvature of the stomach, why there is oxyntic antralization, what the immunological characteristic of gastric chronic inflammation caused by H. pylori is, whether H. pylori infection is associated with extra-gastric diseases, whether chronic atrophic gastritis (CAG) is reversible, and what the potential problems are after H. pylori eradication. What are the possible answers?

CONCLUSION

In the review, we will discuss these issues from the attachment to eradication in detail.

The 'reversibility' of chronic atrophic gastritis after the eradication of Helicobacter pylori

Gram-negative bacterium Helicobacter pylori (H. pylori) infection is lifelong and usually acquired in childhood, which is etiologically linked to gastric cancer (GC). H. pylori gastritis is defined as an infectious disease with varying severity in virtually all infected subjects. Chronic atrophic gastritis (CAG) is the precancerous condition with the decrease or the loss of gastric glands, which can further be replaced by metaplasia or fibrosis. Patients with advanced stages of CAG are at higher risk of GC and should be followed up with a high-quality endoscopy every 3 years. H. pylori infection is the most common cause and its eradication is recommended, which may contribute to the regression of CAG. However, it is controversial whether CAG is reversible after eradication therapy. In the review, we discuss recent studies which provide important insights into whether CAG is 'reversibility' and when it may progress into GC after eradicating H. pylori.

Surveillance strategies for precancerous gastric conditions after Helicobacter pylori eradication: There is still need for a tailored approach

Prevailing evidence declares that Helicobacter pylori (H. pylori) eradication therapy could shift precancerous gastric conditions (PGC) and positively confines gastric cancer (GC) risk during long-term endoscopic follow-up. Nonetheless, there is a yet unsolved controversy regarding the best-individualized surveillance strategies following H. pylori eradication, based on malignant risk stratification. This last dispute is due to the uncertainty of contemporary evidence and the role of H. pylori inflammatory changes in underestimating PGC at the index endoscopy. However, the current state of the art suggests that it is reasonable that high-quality endoscopy with histological assessment for the most accurate diagnosis of PGC may be delayed in selected high-risk patients without alarm signs for malignancy, following the eradication of H. pylori. Notwithstanding, these aspects need to be further examined in the next future to establish and optimize the most beneficial and cost-effective strategies for recognizing and managing H. pylori-positive patients with PGC in the short- and long-term follow-up. Accordingly, additional studies are yet required to sharpen the hazard stratification of patients with the greatest chance of GC evolution, also recognizing the evolving racial, ethnic, immigration factors and the necessity of novel biomarkers to limit GC development or accomplish a diagnosis of malignancy at an early stage.

Significance of Helicobacter pylori Eradication on Atrophic Gastritis and Intestinal Metaplasia

There has been an accumulation of data regarding the chemopreventive effects of <i>Helicobacter pylori</i> (<i>H. pylori</i>) eradication. However, it remains unclear how <i>H. pylori</i> infection causes gastric cancer (GC) and how <i>H. pylori</i> eradication can prevent GC. Atrophic gastritis (AG) and intestinal metaplasia (IM) are known as precancerous lesions which mainly lead to intestinal-type GC but to some extent, can also lead to diffuse-type GC. The most important mechanism of AG/IM is <i>H. pylori</i>-induced chronic gastritis. Thus, the reversibility of AG and IM by <i>H. pylori</i> eradication therapy is very important in the prevention of GC. There have been many studies providing data supporting the improvement of AG by the eradication of <i>H. pylori</i> to some extent. In contrast, IM has been regarded as “the point of no return.” However, more recent studies have implied the improvement of IM after eradication, suggesting the importance of early eradication therapy in reversible histological status. In this review, we focused on the reversibility of AG and IM by <i>H. pylori</i> eradication and tried to investigate the predicting factors for the improvement of AG and IM including age, sex, smoking, and diet, as well as <i>H. pylori</i> infection.

Review of atrophic gastritis and intestinal metaplasia as a premalignant lesion of gastric cancer

Atrophic gastritis (AG) and intestinal metaplasia (IM) are the main precursor lesions of gastric cancer as the incidence of gastric cancer increases in the gastric mucosa involved with AG and IM. The prevalence of AG and IM vary depending on countries, even it represents diverse results in the same nation. Usually AG is antecedent of IM but the etiologies of AG and IM are not always the same. The sensitivity and specificity of diagnostic methods to detect AG and IM are different. Furthermore, the management strategy of AG and IM has not been established, yet. Helicobacter pylori infection has been proved as the most important cause of AG and IM. Thus the eradication of H. pylori is very important to prevent the progression to gastric cancer which is still placed in the high rank in morbidity and mortality among cancers. However, the reversibility of AG and IM by eradication of H. pylori which was assumed to be certain by meta-analysis is; however, controversial now. Therefore, the understanding and early diagnosis of AG and IM are very important, especially, in high incidence area of gastric cancer such as Republic of Korea.

Chronic tamoxifen use is associated with a decreased risk of intestinal metaplasia in human gastric epithelium

BACKGROUND

Intestinal metaplasia (IM), a premalignant lesion, is associated with an increased risk of gastric cancer. Although estrogen exposure, including tamoxifen, has been studied in correlation with gastric cancer, little has been investigated about its effects on IM.

AIMS

Therefore, we investigated whether chronic tamoxifen use was associated with the risk of IM in human stomach.

METHODS

We evaluated 512 gastric biopsies from 433 female breast cancer patients that underwent endoscopic gastroduodenoscopy (EGD) ≥6 months after breast surgery. Histopathological findings were scored according to the updated Sydney classification. Demographic and clinical characteristics were also included to identify predictive factors for IM.

RESULTS

In a multivariate logistic regression analysis, age at EGD (odds ratio [OR], 1.04; P = 0.002), biopsies from antrum (OR 2.08; P < 0.001), and Helicobacter pylori positivity (OR 1.68; P = 0.016) were significantly associated with an increased risk of IM, whereas chronic tamoxifen use (≥3 months) was associated with a decreased risk of IM (OR 0.59; P = 0.025). After stratifying by biopsy site, association between tamoxifen use and IM persisted for corpus (OR 0.42; P = 0.026) but not for antrum (OR 0.74; P = 0.327). In analysis limited to patients with follow-up EGD, chronic tamoxifen use also correlated with improved IM score compared to no tamoxifen use (improved, 77.8 vs. 22.2%; no change, 65.4 vs. 34.6%; worsened, 30.0 vs. 70.0%; P = 0.019).

CONCLUSIONS

This study suggests that chronic tamoxifen use can decrease the risk of IM in human stomach. The effect of tamoxifen is predominantly observed in the corpus.

Histological changes of gastric mucosa after Helicobacter pylori eradication: a systematic review and meta-analysis

AIM

To systematically review pathological changes of gastric mucosa in gastric atrophy (GA) and intestinal metaplasia (IM) after Helicobacter pylori (H. pylori) eradication.

METHODS

A systematic search was made of PubMed, Web of Science, EMBASE, ClinicalTrials.gov, OVID and the Cochran Library databases for articles published before March 2013 pertaining to H. pylori and gastric premalignant lesions. Relevant outcomes from articles included in the meta-analysis were combined using Review Manager 5.2 software. A Begg's test was applied to test for publication bias using STATA 11 software. χ(2) and I(2) analyses were used to assess heterogeneity. Analysis of data with no heterogeneity (P > 0.1, I (2) < 25%) was carried out with a fixed effects model, otherwise the causes of heterogeneity were first analyzed and then a random effects model was applied.

RESULTS

The results of the meta-analysis showed that the pooled weighted mean difference (WMD) with 95%CI was 0.23 (0.18-0.29) between eradication and non-eradication of H. pylori infection in antral IM with a significant overall effect (Z = 8.19; P <0.00001) and no significant heterogeneity (χ(2) = 27.54, I(2) = 16%). The pooled WMD with 95%CI was -0.01 (-0.04-0.02) for IM in the corpus with no overall effect (Z = 0.66) or heterogeneity (χ(2) = 14.87, I(2) =0%) (fixed effects model). In antral GA, the pooled WMD with 95% CI was 0.25 (0.15-0.35) with a significant overall effect (Z = 4.78; P < 0.00001) and significant heterogeneity (χ(2) = 86.12, I(2) = 71%; P < 0.00001). The pooled WMD with 95% CI for GA of the corpus was 0.14 (0.04-0.24) with a significant overall effect (Z = 2.67; P = 0.008) and significant heterogeneity (χ(2) = 44.79, I(2) = 62%; P = 0.0003) (random effects model).

CONCLUSION

H. pylori eradication strongly correlates with improvement in IM in the antrum and GA in the corpus and antrum of the stomach.

Helicobacter pylori and gastric cancer

Infection with Helicobacter pylori is established as the major risk factor for gastric cancer development. Damage of the mucosal barrier due to H. pylori-induced inflammation enhances the carcinogenic effect of other risk factors such as salt intake or tobacco smoking. The genetic disposition of both the bacterial strain and the host can increase the potential towards gastric cancer formation. Genetic variance of the bacterial proteins CagA and VacA is associated with a higher gastric cancer risk, as are polymorphisms and epigenetic changes in host gene coding for interleukins (IL1β, IL8), transcription factors (CDX2, RUNX3) and DNA repair enzymes. Application of high-throughput assays for genome-wide assessment of either genetic structural variance or gene expression patterns may lead to a better understanding of the pathobiological background of these processes, including the underlying signaling pathways. Understanding of the stepwise alterations that take place in the transition from chronic atrophic gastritis, via metaplastic changes, to invasive neoplasia is vital to define the 'point of no return' before which eradication of H. pylori has the potential to prevent gastric cancer. Currently, eradication as preventive strategy is only recommended for high-incidence regions in Asia; large population studies with an adequate follow-up are required to demonstrate the effectiveness of such an approach in Western populations.

Effect of Helicobacter pylori eradication on gastric atrophy and intestinal metaplasia in patients with atrophic gastritis

AIM: To investigate the effect of Helicobacter pylori (H. pylori) eradication on gastric atrophy and intestinal metaplasia in patients with atrophic gastritis.

METHODS: Three hundred and ninety-two patients with atrophic gastritis and intestinal metaplasia who were treated from August 2009 to December 2009 at Shanghai 7^th People's Hospital were enrolled, of whom 300 were followed for 1 and 3 years by narrow band imaging-magnifying endoscopy (NBI-ME) and histopathological analysis after H. pylori eradication.

RESULTS: In patients with successful eradication, grades of disease activity and chronic inflammation significantly decreased at 1 year (in the antrum: 1.41 ± 0.64 vs 1.21 ± 0.65, 1.83 ± 0.59 vs 1.43 ± 0.50; in the corpus: 1.36 ± 0.67 vs 1.18 ± 0.67, 1.71 ± 0.46 vs 1.35 ± 0.48, all P < 0.005) and 3 years (in the antrum: 1.51 ± 0.62 vs 1.31 ± 0.69, 1.97 ± 0.60 vs 1.46 ± 0.50; in the corpus: 1.48 ± 0.65 vs 1.26 ± 0.69, 1.90 ± 0.56 vs 1.46 ± 0.50, all P < 0.005). The grade of corpus atrophy also significantly decreased at 1 year (1.54 ± 0.65 vs 1.36 ± 0.68, P < 0.005) and 3 years (1.68 ± 0.65 vs 1.50 ± 0.69, P < 0.005) after successful eradication. However, there was no significant change in intestinal metaplasia in both the antrum and corpus.

CONCLUSION: Eradication of H. pylori results in the alleviation of the severity of gastritis and the reversion of gastric atrophy in the corpus.

Predictive factors for improvement of atrophic gastritis and intestinal metaplasia after Helicobacter pylori eradication: a three-year follow-up study in Korea

BACKGROUND AND AIMS

To date, data on the effects of anti-Helicobacter therapy on the improvement of atrophic gastritis (AG) and intestinal metaplasia (IM) have been conflicting. This study was performed to investigate whether eradication of H. pylori could lead to the improvement of AG and IM, and the prognostic factors associated with the improvement of AG and IM.

METHODS

Four hundred patients consisting of H. pylori-negative (n = 116) and H. pylori-positive (n = 284) groups were followed up 1 and 3 years after initial H. pylori tests. Serum levels of pepsinogen (PG), bacteria, environmental factors, and genetic polymorphisms were determined.

RESULTS

The grade of corpus atrophy decreased at 1 and 3 years after successful eradication (p < .001 and p = .033, respectively). However, there was no significant change in the IM in the antrum and in the corpus. Prediction factors for the improvement of corpus AG by H. pylori eradication were baseline low PG I/II ratio (≤3), high salt intake, and corpus-predominant gastritis. IM improvement was also associated with spicy food intake and high baseline grade of IM, in addition to these factors. In addition, IL-1B-511 C/T and IL-6-572 C/G alleles were found to inhibit IM improvement. However, H. pylori-negative and noneradicated group did not show any significant change in AG or IM.

CONCLUSION

Corpus AG was reversed by H. pylori eradication, and improvement of IM by H. pylori eradiation was more definite in patients with severe IM, low PG I/II ratio, and corpus-predominant gastritis, suggesting that H. pylori eradication is valuable even in severe cases.

Reversal of atrophic body gastritis after H. pylori eradication at long-term follow-up

BACKGROUND

The effect of Helicobacter pylori treatment on the potential reversal of atrophic body gastritis (ABG) is controversial. Body atrophy reversal was evaluated in a cohort of H. pylori-negative and treated H. pylori-positive ABG patients.

METHODS

Observational long-term follow-up cohort study including 300 ABG patients with at least one follow-up gastroscopy with three biopsies from the antrum and three from the body performed no earlier than 1 year after diagnosis was included. H. pylori was diagnosed by Giemsa-stain and serology. H. pylori-positive patients (n = 192) were treated with bismuth-based triple regimen.

RESULTS

After a mean follow-up of 5.2 years, body atrophy reversal was observed in 42/300 patients (14%). Body atrophy reversal occurred more frequently in patients treated for H. pylori than in H. pylori-negative ones (21.3% vs 0.9%, p < 0.00001) and was observed between 2 and 8 years after treatment in 52% of cases. Predictive factors for body atrophy reversal at Cox-regression analysis were mild atrophy (HR 2.14; 95% CI 1.12-4.1), moderate-severe inflammation (HR 5.3; 95% CI 1.64-17.3), and absence of intestinal metaplasia (HR 2.4; 95% CI 1.2-4.8).

CONCLUSION

Body atrophy reversal was observed in about 20% of ABG patients treated for H. pylori infection, and about 50% of reversals occurred during long-term follow-up.

Eradication of Helicobacter pylori infection improved gastric mucosal atrophy and prevented progression of intestinal metaplasia, especially in the elderly population: a long-term prospective cohort study

BACKGROUND AND AIMS

It still remains controversial whether gastric mucosal atrophy and intestinal metaplasia are reversible after eradication of Helicobacter pylori infection. The aims of this study were to evaluate the histological changes in gastric mucosa after H. pylori eradication during long-term follow-up periods, and to verify the propriety of H. pylori eradication for the elderly population.

METHODS

Two hundred and forty-one patients with H. pylori infection and 84 cases more than 60 years old were classified as the elderly group. The mean follow-up period was 101 months. A series of endoscopic examinations with five-point biopsies were performed before and every year after H. pylori eradication. We evaluated the histological grades according to the Updated Sydney System. Statistical analysis was performed using the Wilcoxon signed rank test and the Mann-Whitney U-test, and P < 0.05 was considered to be statistically significant.

RESULTS

The atrophic grades improved only at the angle in the 5th year and at all points, except for the antrum, in the 10th year after H. pylori eradication. In the elderly group, the atrophic score improved in both the 5th and 10th year. However, improvement in the younger group was achieved only in the 10th year. The metaplastic score did not change in either the 5th or 10th year after H. pylori eradication in all patients.

CONCLUSION

Eradication of H. pylori infection improved gastric atrophy and prevented the progression of intestinal metaplasia in the elderly population during the long-term follow-up periods. H. pylori eradication for the elderly population is effective.

Helicobacter pylori eradication improves gastric histology and decreases serum gastrin, pepsinogen I and pepsinogen II levels in patients with duodenal ulcer

BACKGROUND AND AIM

The aim of this study was to assess the gastric histopathology and serum gastrin-17 and pepsinogens profiles in patients with duodenal ulcer before and after Helicobacter pylori eradication in a population with a very high prevalence of H. pylori. At the same time we assessed the role of H. pylori density on these variables.

METHODS

Eighty Caucasian patients with H. pylori-associated duodenal ulcer before treatment and 1 year after randomized eradication were studied. Among patients with unsuccessful eradication two groups were distinguished according to the data obtained after treatment: the group with negative rapid urease test and decreased bacterial density according to morphological score (partial elimination group); the group with positive rapid urease test and high bacterial density (failed eradication group).

RESULTS

One year after successful eradication, serum levels of gastrin-17, pepsinogen I and pepsinogen II decreased. Similar changes of serum pepsinogen I and pepsinogen II levels were observed in patients with partial elimination of H. pylori infection. In the group with successful eradication, inflammation, activity, atrophy and number of lymphoid follicles in the antral mucosa fell. In the group with partial elimination, antral mucosa activity and H. pylori score reduced. Other morphological changes were statistically non-significant.

CONCLUSION

Patients with duodenal ulcer after successful eradication have improvement of morphological and functional characteristics of gastric mucosa.

The long-term impact of Helicobacter pylori eradication on gastric histology: a systematic review and meta-analysis

BACKGROUND

Helicobacter pylori infection is a crucial factor in the multistep carcinogenic process of gastric cancer. In this process the gastric mucosa evolves through the stages of acute gastritis, chronic gastritis, gastric atrophy (GA), and intestinal metaplasia (IM) before developing gastric adenocarcinoma.

AIMS

The main aim of this study was to systematically review the long-term effects of H. pylori eradication on gastric histology (i.e. effects on GA and IM for both antrum and corpus) by meta-analyzing all relevant studies.

METHODS

Extensive English-language medical literature searches for human studies were performed through October 2006, using suitable key words. Pooled estimates [odds ratio (OR) with 95% confidence intervals (CI)] were obtained using random-effects model.

RESULTS

For antrum GA the pooled OR with 95% CI was 0.554 (0.372-0.825), p=0.004. For corpus GA the pooled OR was 0.209 (0.081-0.538), p<0.001. For antrum IM the pooled OR was 0.795 (0.587-1.078), p=0.14. For corpus IM the pooled OR was 0.891 (0.663-1.253), p=0.506.

CONCLUSION

The results showed significant improvement of GA, whereas improvement was not shown for IM.

Feasibility and cost-effectiveness of using magnification chromoendoscopy and pepsinogen serum levels for the follow-up of patients with atrophic chronic gastritis and intestinal metaplasia

BACKGROUND

The follow-up of patients with atrophic chronic gastritis or intestinal metaplasia may lead to early diagnosis of gastric cancer. However, to-date no cost-effective model has been proposed. Improved endoscopic examination using magnification chromoendoscopy together with non-invasive functional assessment with pepsinogen serum levels are accurate in the diagnosis of intestinal metaplasia (extension) and minute dysplastic lesions. The aim of this study was to assess the feasibility and cost-effectiveness of a follow-up model for patients with atrophic chronic gastritis and intestinal metaplasia based on gastric mucosal status using magnification chromoendoscopy and pepsinogen.

METHODS

A cohort of patients with lesions as severe as atrophic chronic gastritis were followed-up according to a standardized protocol using magnification chromoendoscopy with methylene blue and measurement of serum pepsinogen I and II levels. A single node decision tree and Markov chain modeling were used to define cost-effectiveness of this follow-up model versus its absence. Transition rates were considered time-independent and calculated using primary data following cohort data analysis. Costs, quality of life and survival were estimated based on published data and extensive sensitivity analysis was performed.

RESULTS

A total of 100 patients were successfully followed-up over 3 years. Seven cases of dysplasia were diagnosed during follow-up, all among patients with incomplete intestinal metaplasia at baseline, six of whom had extensive (pepsinogen I to II ratio <3) incomplete intestinal metaplasia. For those individuals with atrophic chronic gastritis or complete intestinal metaplasia, a yearly measurement of pepsinogen levels or an endoscopic examination on a 3-yearly basis would cost 455 euros per quality-adjusted life year (QALY) gain. Endoscopic examination and pepsinogen serum level measurement on a yearly basis would cost 1868 euros per QALY for patients with extensive intestinal metaplasia.

CONCLUSIONS

The follow-up of patients with atrophic chronic gastritis or intestinal metaplasia is both feasible and cost-effective if improved accurate endoscopic examination of gastric mucosa together with non-invasive assessment of gastric mucosal status are used to identify individuals at high-risk for development of gastric cancer.

Serum-free culture of H pylori intensifies cytotoxicity

AIM: To perform a long culture passage of H pylori without serum, taking into account its cytotoxicity and the presence of the probable new cytotoxic factor.

METHODS: One sample of H pylori 60190 (ATCC 49503) was grown on Brain Heart Infusion (BHI) agar containing 0.5% 2,6-di-O-methyl-β-cyclodextrin without any serum, being passaged 70-100 times every 3-4 d for approximately 2 h, while another sample of H pylori contained 70 mL/L fetal calf serum without 2,6-di-O-methyl-β-cyclodextrin. Their supernatant and extract after 16 h in culture were evaluated for changes in cell morphology and for cell viability using HeLa cells. Furthermore, the characteristics of the probable cytotoxic factor in the extract were examined on partial purification studies and its cytotoxicity was evaluated in various human cells.

RESULTS: The supernatant and the extract of the bacterium grown on serum-free medium had strong cytotoxicity compared with those grown on serum-containing medium. They irreversibly damaged HeLa cells without vacuolation that was altogether different from that of the bacterium when grown with serum. Their cytotoxicity was easily measured by cell viability assay. The probable cytotoxic factor partially purified and detected by chromatography had characteristics difference from that of vacuolating toxin and a broad cytotoxicity toward various cell lines.

CONCLUSION: Serum-free long culture method of H pylori makes its supernatant and its extract cytotoxic enough to be easily measured by cell viability assay. The probable cytotoxic factor has a unique characteristic and might be a new cytotoxin.

Systematic review: Helicobacter pylori eradication for the prevention of gastric cancer

BACKGROUND

Helicobacter pylori is recognized as one of the most significant risk factors for gastric cancer, and H. pylori eradication has been proposed as a possible primary chemo-preventive strategy to reduce gastric cancer incidence.

AIM

To evaluate the available evidence on the efficacy of H. pylori eradication in the prevention of gastric cancer.

METHODS

Epidemiological, observational and interventional studies, as well as decisional models, were taken into account in this review.

RESULTS

Large-scale epidemiological studies clearly link H. pylori infection with non-cardia gastric cancer. Current evidence suggests that, in a subpopulation of treated subjects, H. pylori eradication prevents the progression of preneoplastic lesions. Studies that have attempted to evaluate the effect of H. pylori eradication on the incidence of gastric cancer have not provided definitive answers. H. pylori eradication seems to reduce the incidence of gastric cancer in patients without baseline precancerous gastric lesions. Decisional models suggest that H. pylori screening could be cost-effective, but there is not yet sufficient evidence to support the setting up of a general screening programme.

CONCLUSION

Helicobacter pylori eradication is a plausible intervention for gastric cancer prevention; however, it seems to be relevant in only a subset of subjects.

Helicobacter pylori eradication and associated changes in the gastric mucosa

Persistent Helicobacter pylori infection contributes towards the development of chronic gastritis. To clarify the changes in chronic gastritis as a precursor of gastric cancer secondary to H. pylori eradication is an important issue, as it has significant implications for reducing the risk of gastric cancer. Studies published to date, however, are far from consistent with regard to the morphologic changes reported following H. pylori eradication. Of these, some papers reported improvement in gastric atrophy or intestinal metaplasia, versus others reporting no improvement, with the majority of papers published after 2000 reporting improvement in these end points. The inconsistent results concerning the impact of H. pylori eradication on gastric atrophy could be due to the inconsistency of the diagnostic criteria employed for evaluation of the morphology, confounded by the difficulties involved in evaluating atrophic changes in the gastric mucosa. While adherence to the Updated Sydney System available for evaluation of gastritis is primarily required worldwide to ensure consistency in evaluating gastritis, long-term research into the morphologic changes associated with H. pylori eradication is also required to explore strategies for the prevention of gastric cancer with H. pylori eradication.

Helicobacter pylori eradication in the healing of atrophic gastritis: a one-year prospective study

OBJECTIVE

Whether gastric atrophy or intestinal metaplasia heals after successful treatment of Helicobacter pylori (H. pylori) infection is still a matter of controversy. The aim of this article was to clarify whether, after one year, H. pylori eradication is associated with healing in glandular atrophy and intestinal metaplasia in the corpus and antrum.

MATERIAL AND METHODS

Ninety-two H. pylori-positive peptic ulcer patients with atrophic gastritis (panatrophy, antral or corpus predominant) participated in the baseline study, 1-year prospective follow-up data being available from 76 patients. Mean age was 58+/-12.6 years (mean+/-SD) and the male/female ratio 2/1. The patients participated in an H. pylori eradication study in which they randomly received active eradication therapy. Endoscopy was performed before H. pylori eradication therapy and after 8 and 52 weeks, with specimens examined according to the Sydney system.

RESULTS

Of the 92 patients, 8 (9%) had panatrophy, 58 (63%) had antral- and 26 (28%) had corpus-predominant atrophic gastritis. After H. pylori eradication, the mean atrophy score declined in patients with antral-predominant atrophy from 1.5 (mean) to 0.7 (p<0.05), in corpus-predominant atrophy from 1.7 to 0.2 (p=NS) and in patients with panatrophy from 1.2 to 0.8 (p=NS). Atrophy healing was seen in 55% of antral-predominant atrophy patients who had successful H. pylori eradication. The mean antral atrophic score in one year declined in patients with duodenal ulcer (from 1.0 mean to 0.4) whereas it remained the same (1.3) in those with gastric ulcer (p<0.05).

CONCLUSIONS

Atrophy can diminish or even disappear, especially in the antrum, during a 1-year follow-up after eradication of infection. Atrophy progression seems milder in patients with duodenal ulcer than in patients with gastric ulcer.

Recovery of gastric function after Helicobacter pylori eradication in subjects with body atrophic gastritis: prospective 4-year study

BACKGROUND

The relationship between Helicobacter pylori (H. pylori) eradication and atrophic changes in the gastric mucosa has not yet been fully defined. Although studies report a partial restoration of serum pepsinogen I (sPGI) levels after eradication, it is not clear if this finding reflects gastric mucosal healing on a morphological level.

AIM

To assess alterations in gastric function after H. pylori eradication on moderate/severe body atrophic gastritis by determination of sPGI levels.

METHODS

Twenty-three dyspeptic patients, selected from 284 consecutive H. pylori positive patients, with histological features of moderate/severe body atrophic gastritis and sPGI < 25 microg/L (11 men, mean age: 51.8 years, range: 29-79 years), underwent an upper gastrointestinal endoscopy with gastric biopsies and sPGI determination at baseline. All patients underwent eradication therapy. Serum pepsinogen I was measured again after 6 months, and at 1, 2, 3 and 4 years after eradication therapy.

RESULTS

Mean sPGI levels prior to eradication were 11.9 microg/L (range: 4-23 microg/L). Six months after eradication therapy, mean sPGI levels significantly increased to 17.4 microg/L (P = 0.04). At the completion of the study, 4 years after eradication, sPGI levels increased from 17.4 to 32.7 microg/L (P = 0.01). A significant progressive increase in sPGI levels was observed from 6 months to 1 year (17.4 to 23.9 microg/L) and from 1 to 2 years (23.9 to 26.0 microg/L, P = 0.01). Serum pepsinogen I levels higher than the cut-off value of 25 microg/L were observed at various time-points: 6.3% of patients at 6 months (1/16), 33.3% (5/15) at 1 year, 50% (7/14) at 24 months, 66.7% (6/9) at 36 months and 87.5% (7/8) at 4 years.

CONCLUSION

After H. pylori eradication, subjects with body atrophic gastritis showed long-term improvement of physiological gastric function, reflected by significantly and continually increasing sPGI levels over a 4-year period.

Helicobacter pylori eradication has the potential to prevent gastric cancer: a state-of-the-art critique

Helicobacter pylori infection continues to play a key role in gastric diseases. Colonization of the gastric mucosa with the bacterium invariably results in the development of chronic gastritis and subsets of patients have a progression of the chronic gastritis to either ulcer or cancer. Epidemiological evidence indicates that the proportion of all gastric cancers attributable to H. pylori infection, and hence potentially preventable upon elimination of this risk factor, is somewhere in the range of 60% to 90%. This portends significant benefit in terms of morbidity and mortality, not least in populations with high prevalence of H. pylori infection coupled with high incidence of gastric cancer. The effect of prophylactic H. pylori eradication on gastric cancer incidence in humans remains unknown, however. Results from randomized trials are eagerly awaited, but availability of strong conclusive results may take many years. A growing number of studies show considerable variation in risk for gastric cancer development, depending on H. pylori strain type and the genetic predisposition of the host. There is also a remote possibility that elimination of the infection may have adverse health implications (e.g., antibiotic resistance), and therefore "simple" risk stratification and targeted chemoprevention is required. Based on "in depth" evidence presented at this workshop, the majority of the scientific task force favored a search-and-treat strategy in first-degree relatives of gastric cancer patients and an overwhelming majority felt that a more general screen-and-treat strategy should be focused in the first instance on a population with a high incidence of H. pylori-associated diseases.

A follow-up study on the effect of Helicobacter pylori eradication on the severity of gastric histology

Helicobacter pylori genetic diversity and geographic distribution affect the severity of gastric histology; while eradication heals gastritis, the improvement of atrophy and intestinal metaplasia (IM) is still controversial. We investigated whether H. pylori infection and genotypes (cagA-vacA) influence the histological changes and whether eradication resolves these changes. Twenty-one patients (11 duodenal ulcer, 2 gastric ulcer, 8 gastritis) received treatment. Biopsies for CLO, PCR, histology, and culture were collected before and at 1 and 12 months after treatment, and serum samples at 0, 1, 2, 6, and 12 months. H. pylori eradication was achieved in 71% of the patients. Histological scores for H. pylori densities were significantly higher in the antrum and incisura angularis. Scores for mononuclear cell and neutrophil infiltration were significantly higher in regions with a high H. pylori density and improved progressively after eradication. Eight patients with atrophy including five with IM showed no significant changes 12 months after eradication. The cagA gene, detected in 13 (62%), the vacA-sla gene, in 20 (95%), and the vacA-m1 gene, in 12 (57%) of 21 patients were significantly associated with duodenal ulcer. A gradual decline in antibody titer reached an average of 67% 12 months after eradication. H. pylori infection and the associated genotypes (cagA of Western type) affect the severity of the gastric histology (mild forms of atrophy and IM) and the disease outcome. Eradication of H. pylori resulted in healing of gastritis, but with no significant improvement in atrophy or IM.

A negative Helicobacter pylori serology test is more reliable for exclusion of premalignant gastric conditions than a negative test for current H. pylori infection: a report on histology and H. pylori detection in the general adult population

OBJECTIVE

Corpus-dominant gastritis, gastric mucosal atrophy and intestinal metaplasia (IM) associated with Helicobacter pylori infection are all known potential risk markers for the development of gastric cancer. As the accuracy for finding cases at risk in the general population is unknown, we aimed to determine the prevalence of current and/or past H. pylori infection and associated gastric mucosal findings by means of histological survey of a random adult population.

MATERIAL AND METHODS

A random Swedish sample (n = 3000, age 20-81 years) was surveyed using a validated gastrointestinal symptom questionnaire with 74% response rate. One-third of the responders were selected at random for esophago-gastro-duodenoscopy with biopsies and H. pylori serology.

RESULTS

Of those endoscoped (n = 1000, mean age 53.5, 51% women), 43.0% were H. pylori+ by serology (seropositive), 33.9% had signs of current infection on either histology or culture (gold standard+), and 9.3% were seropositive, but gold standard negative. Corpus atrophy was found in 10% and IM in 13% when gold standard positive, and in a significantly higher number (17% and 21%, respectively) of those with only a serological sign of past infection. Among those who were seronegative, values were 1% and 2%, respectively. Corpus-dominant gastritis was found in 4.1%, all seropositive.

CONCLUSION

One-third had an ongoing H. pylori infection, and a further 10% had signs of past infection. Corpus-dominant gastritis was found mostly among the former, while detection of those with corpus atrophy and IM also required a test for past infection. Seronegativity almost excludes precancerous conditions in a screening situation.

Review article: helicobacter pylori and molecular events in precancerous gastric lesions

Gastric cancer can be divided into intestinal type and diffuse type that differ substantially in epidemiology and pathogenesis. The most important aetiological factor associated both with intestinal and diffuse gastric cancer, is Helicobacter pylori. Exposure of gastric epithelial cells to H. pylori results in an inflammatory reaction with the production of reactive oxygen species and nitric oxide that, in turn, deaminates DNA causing mutations. The complex interplay between H. pylori strain, inflammation and host characteristics may directly promote diffuse type gastric cancer or induce a cascade of morphological events, i.e. atrophy, intestinal metaplasia and dysplasia, finally leading to intestinal type gastric cancer. Two mechanisms, genetic and epigenetic have been held to play a role in the molecular alterations underlying gastric carcinogenesis. The former, comprising changes in the DNA sequence, is irreversible; the latter, involving DNA methylation, is potentially reversible by eliminating the triggering agents. If H. pylori is eradicated before development of stable mutations, the risk of gastric cancer will likely be prevented. Thus, eradication of H. pylori might immediately reduce the risk of diffuse type gastric cancer, whereas prevention of intestinal type gastric cancer may be less effective if patients are treated later in the evolution of the carcinogenic process.

Clinical evaluation of four one-week triple therapy regimens in eradicating Helicobacter pylori infection

AIM: To evaluate clinical efficacy of four one-week triple therapies in eradicating Helicobacter pylori infection.

METHODS: In this clinical trial, 132 patients with duodenal ulcer and chronic gastritis were randomly divided into four groups, and received treatment with OAC (omeprazole 20 mg + amoxicillin 1000 mg + clarithromycin 250 mg), OFC (omeprazole 20 mg + furazolidone 100 mg + clarithromycin 250 mg), OFA (omeprazole 20 mg + furazolidone 100 mg + amoxicillin 1000 mg) and OMC (omeprazole 20 mg + metronidazole 200 mg + clarithromycin 250 mg), respectively. Each drug was taken twice daily for one week. The ¹³C urea breath test was carried out 4-8 weeks after treatment to determine the success of H pylori eradication.

RESULTS: A total of 127 patients completed the treatment. The eradication rate for H pylori infection was 90.3%, 90.9%, 70.9% and 65.6%, respectively in OAC, OFC OMC and OFA groups.

CONCLUSION: A high eradication rate can be achieved with one-week OAC or OFC triple therapy. Thus, one-week triple therapies with OAC and OFC are recommended for Chinese patients with duodenal ulcers and chronic gastritis.

Effects of H. pylori eradication with liaowei decoction on pathology of H. pylori-associated chronic gastritis in rats

AIM: To evaluate the effects of H. pylori eradication with liaowei decoction on pathologic changes and COX-2 expression of H. pylori-associated chronic gastritis in rats.

METHODS: A total of 80 grade-II male Wister rats weighing 80-100 g were given H. pylori and MNNG to prepare H. pylori-associated chronic gastritis model with 4 mice dead. Among them, 54 rats with H. pylori serum antibody positive were randomly divided into 4 groups: H. pylori eradication with liaowei decoction (14 rats); H. pylori eradication with Maizilin (positive control, 14 rats); spontaneous recovery (negative control, 13 rats); and simple H. pylori eradication therapy (13 rats). After treatment, both Gram staining of gastric antrum mucosal smear and rapid urease testing were made to detect the H. pylori colonization of the gastric mucosa and to assess the histological indexes of gastric antrum mucosa. Immunohistochemical staining was also performed to detect COX-2 expression.

RESULTS: The colonization of gastric mucosa by H. pylori was found in rats from spontaneous recovery group, as an indication of long-term continuous H. pylori infection, while no colonization was found in rats from other groups. Pathological changes of gastric antrum mucosa included moderate gastric mucosal atrophy in rats from spontaneous recovery group (pathologic integration 2.0±0.20 points), associatded with moderate acute or chronic gastric mucosal inflammation (pathologic integrations were 2.0±0.20 points and 1.90±0.39 points, respectively). In comparison with spontaneous recovery group, treatment effectiveness in the group of H. pylori eradication with liaowei decoction was remarkably different (P < 0.05). The gastric mucosal atrophy in the combination group (pathologic integration 1.25±0.44 points) was less severe, while acute gastric mucosal inflammation (pathologic integration 0.3±0.47 points) was extincted, and chronic inflammation (pathologic integration 1.05±0.22 points) was less severe; For the group of H. pylori eradication and "Maizilin", pathologic integration of gastric mucosal atrophy was 2.0±0.43 points. In comparison with spontaneous recovery group, there was no remarkable difference, however, acute inflammation was extincted and chronic inflammation was the same as before. Gastric mucosal atrophy and chronic inflammation were more severe in simple H. pylori eradication group than those in spontaneous recovery group, while active inflammatory changes extincted. COX-2 expression of gastric antrum mucosa in the group of simple H. pylori eradication, group of H. pylori eradication with liaowei decoction, group of H. pylori eradication and Maizilin as well as spontaneous recovery group were 14%±3.7%, 10%±3.8%, 13%±4.0% and 19%±10.2%, respectively. In comparison with spontaneous recovery group, COX-2 expression of the treatment groups were greatly decreased as an indication of remarkable difference (P < 0.05).

CONCLUSION: COX-2 expression and acute inflammation can be greatly decreased by applying H. pylori eradication therapy in the treatment of H. pylori-associated chronic gastritis, but the therapy cannot do much to chronic pathologic changes, especially to atrophic changes. Application of the combined therapy of H. pylori eradication with "liaowei decoction" for 12 weeks will have better treatment effectiveness on chronic pathologic changes, especially atrophic changes.