Gastric exocrine and endocrine cell morphology under prolonged acid inhibition therapy: results of a 5-year follow-up in the LOTUS trial

Rebound of Reflux-Related Symptoms After Helicobacter pylori Eradication in Patients With Gastroesophageal Reflux Disease: A Prospective Randomized Study

BACKGROUND/PURPOSE

We aimed to assess the effects of Helicobacter pylori (H. pylori) eradication on the rebound of reflux-related symptoms among gastroesophageal reflux disease (GERD) patients.

METHODS

This prospective randomized study recruited patients with typical reflux symptoms and reflux esophagitis on esophagogastroduodenoscopy (NCT02934152). Patients positive for H. pylori via a urea breath test (UBT) were randomly assigned to receive bacterial eradication with triple therapy for 2 weeks either before or after proton-pump inhibitor (PPI) treatment for 4 weeks. Follow-up was implemented with serial GerdQ evaluation and a subsequent UBT. The primary outcome was the incidence rates of symptom rebound between patients with and without H. pylori infection. The secondary outcomes included the severity of symptom rebound, incidence rates of symptom rebound, and successful eradication rates between the early and late eradication groups.

RESULTS

A total of 248 patients were enrolled, of whom 107 (43.1%) tested positive for H. pylori infection. All patients with and without concurrent H. pylori infection had significant symptom improvement over the entire treatment. Patients with H. pylori infection had significantly lower rates of symptom rebound (19.8% vs. 34.2%, p = 0.034) and rebound severity (1.8 ± 0.7 vs. 2.8 ± 1.6, p = 0.031) 4 weeks after eradication and PPI treatment than those without. The incidence rates of symptom rebound and successful eradication rates were not significantly different between the early and late eradication groups.

CONCLUSIONS

GERD patients with concurrent H. pylori infection were less susceptible to symptom rebound after H. pylori eradication compared to those without.

TRIAL REGISTRATION

ClinicalTrial.gov (NCT02934152).

Proton pump inhibitors are not associated with fundic gland polyps - a systematic review that takes into consideration all known confounders

Sporadic fundic gland polyps (FGPs) progress, albeit rarely, to dysplasia and cancer. Two meta-analyses, including 8 and 11 studies, concluded that proton pump inhibitors (PPIs) were associated with FGPs. Intervention is considered unnecessary when FGPs have a background of PPIs use. Both meta-analyses, however, disregarded known confounders: age, sex, endoscopy indications, study design (prospective or retrospective), duration of PPI use, and H. pylori infection. Confounders are known to invalidate meta-analyses. We followed PRIXMA guidelines and searched the literature for studies on FGPs in PPI-users and PPI-nonusers. In the 22 studies searched, we compared FGPs in PPI-users (n = 6534) and PPI-nonusers (n = 41 115). Heterogeneity was significant (Cochran Q = 277.8, P < 0.0001; I2 = 92.8%), annulling meta-analysis performed by blanket tallying. To offset the above confounders, we matched PPI-users and PPI-nonusers by (a) age and sex (n = 4300 and 29 307, respectively) and (b) their propensity scores derived from the confounders (n = 2950 and 4729, respectively). After both matching, FGPs were not significantly different between PPI-users and PPI-nonusers [odds ratio (OR) = 1.1, P = 0.3078; OR = 0.9, P = 0.3258, respectively]. Furthermore, FGP frequency did not correlate with increasing duration of PPI use (Pearson and Spearman correlation coefficients = 0.1162, 0.0386, P < 0.6064, 0.8646, respectively); it was not significantly different between any of the duration periods of observation, namely, <10, 10-20, 20-40, >40 months, nor was it significantly different between PPI-users and PPI-nonusers within each duration period (P > 0.05). We conclude that PPIs are not associated with FGPs, implying that a background history of PPI use is not a justification for nonintervention in the management of FGPs.

Whether long-term use of proton pump inhibitor increases the risk of precancerous lesions in the stomach: A systematic review and meta-analysis of randomized controlled trials

BACKGROUND

To evaluate through meta-analysis whether long-term use of proton pump inhibitor (PPI) increases the risk of precancerous lesions in the stomach.

METHODS

Randomized controlled trials that compared the occurrence and progression of precancerous lesions in patients receiving PPI treatment versus non-PPI treatment were retrieved from CNKI, VIP, Wanfang, CBM, Pubmed, Embase, Web of Science, and Cochrane Library databases (from database inception to May 1, 2023). The Revman 5.3 and STATA 17.0 software were used for analysis, and subgroup analysis was conducted based on follow-up time (≤12 months and > 12 months) and lesion type (atrophic gastritis, intestinal metaplasia, and epithelial dysplasia).

RESULTS

Six randomized controlled trials with a total of 1623 cases were included, including 1015 cases in the experimental group and 608 cases in the control group. The meta-analysis results showed that the overall abnormal lesion rate combined with statistical relative risk (RR) = 1.31 (0.85-2.02), P = .23. Subgroup analysis showed that the follow-up time > 12 months combined result was RR = 2.21 (1.47-3.33), P = .0001, the intestinal metaplasia group combined result was RR = 1.96 (0.91-2.47), P = .04.

CONCLUSION SUBSECTIONS

During long-term follow-up, patients using PPI exhibited a significantly higher incidence of overall abnormal lesions compared to the control group, particularly with a higher risk observed for intestinal metaplasia. However, there were no statistically significant differences between the 2 groups in terms of short-term follow-up and other types of lesions. It is important to exercise caution when interpreting these findings due to the limited number of nominated investigations included in the meta-analysis.

Gastric Cancer Risk in Patients with Long-Term Use of Proton Pump Inhibitors: A Systematic Review and Meta-Analysis of Observational and Interventional Studies

BACKGROUND

A growing number of studies that differ in design, quality, and results report an association between the use of proton pump inhibitors (PPIs) and the risk of gastric cancer (GC). We conducted a systematic review and meta-analysis, when possible, of observational and interventional studies examining PPI use and risk of GC.

METHODS

We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We identified studies fully published in English through January 2023 using MeSH and non-MeSH keywords. We used random effects models to calculate pooled risk estimates with 95% confidence interval (CI) between PPI use and overall GC, cardia GC, and non-cardia GC. We estimated heterogeneity (I2) among studies. We examined the effect of study design and quality, GC site, H. pylori infection, and PPI duration. We assessed quality using the Newcastle-Ottawa Quality Assessment Scale and Risk Of Bias In Non-randomized Studies of Interventions.

RESULTS

We identified 15 observational studies, of which 13 were included in the meta-analysis (six cohort and seven case-control). There was a modest 1.67-fold increase in overall GC risk (95% CI 1.39, 2.00) and no increase in cardia GC risk [odds ratio (OR) 1.12; 95% CI 0.80, 1.56] with PPI use. However, there was high heterogeneity (I2 = 61.3%, p = 0.004) among studies. All but one study had at least moderate risk of bias. In the six studies accounting for H. pylori, GC risk associated with PPI use increased slightly (OR 1.78; 95% CI 1.25, 2.52). Duration response was not reported consistently to allow pooled estimates. We identified only one interventional randomized controlled study that included GC as an outcome of interest, and it did not show increased GC risk.

CONCLUSIONS

The overall available evidence is not supportive of a meaningful change in GC risk, either cardia or non-cardia, with PPI use.

Long-term proton pump inhibitors use and its association with premalignant gastric lesions: a systematic review and meta-analysis

Background: Long-term maintenance therapy with proton pump inhibitors (PPIs) is a common treatment strategy for acid-related gastrointestinal diseases. However, concerns have been raised about the potential increased risk of gastric cancer and related precancerous lesions with long-term PPI use. This systematic review and meta-analysis aimed to evaluate this potential risk. Methods: We searched PubMed, Embase, and the Cochrane Central Register of Controlled Trials for randomised controlled trials published before 1 March 2023, with no language restrictions. The primary endpoint was the occurrence and progression of gastric mucosal atrophy, intestinal metaplasia, Enterochromaffin-like (ECL) cell hyperplasia, gastric polyps, and gastric cancer during the trial and follow-up. Data were analysed using a random effects model. Results: Of the 4,868 identified studies, 10 met the inclusion criteria and were included in our analysis, comprising 27,283 participants. Compared with other treatments, PPI maintenance therapy for more than 6 months was associated with an increased risk of ECL cell hyperplasia (OR 3.01; 95% CI 1.29 to 7.04; p = 0.01). However, no significant increase was found in the risk of gastric mucosal atrophy (OR 1.01; 95% CI 0.55 to 1.85; p = 0.97), intestinal metaplasia (OR 1.14; 95% CI 0.49 to 2.68; p = 0.76), gastric polyps (OR 1.13; 95% CI 0.68 to 1.89; p = 0.64), or gastric cancer (OR 1.06; 95% CI 0.79 to 1.43; p = 0.71). Conclusion: This systematic review and meta-analysis does not support an increased risk of gastric cancer or related precancerous lesions with long-term PPI maintenance therapy. However, long-term PPI use should be monitored for potential complications such as ECL cell hyperplasia. Further studies are needed to confirm these findings and evaluate the safety of PPI maintenance therapy for acid-related gastrointestinal diseases. Systematic Review Registration: https://www.crd.york.ac.uk/prospero/, Identifier: PROSPERO (CRD42022379692).

Management of Helicobacter pylori infection: the Maastricht VI/Florence consensus report

Helicobacter pyloriInfection is formally recognised as an infectious disease, an entity that is now included in the International Classification of Diseases 11th Revision. This in principle leads to the recommendation that all infected patients should receive treatment. In the context of the wide clinical spectrum associated with Helicobacter pylori gastritis, specific issues persist and require regular updates for optimised management.The identification of distinct clinical scenarios, proper testing and adoption of effective strategies for prevention of gastric cancer and other complications are addressed. H. pylori treatment is challenged by the continuously rising antibiotic resistance and demands for susceptibility testing with consideration of novel molecular technologies and careful selection of first line and rescue therapies. The role of H. pylori and antibiotic therapies and their impact on the gut microbiota are also considered.Progress made in the management of H. pylori infection is covered in the present sixth edition of the Maastricht/Florence 2021 Consensus Report, key aspects related to the clinical role of H. pylori infection were re-evaluated and updated. Forty-one experts from 29 countries representing a global community, examined the new data related to H. pylori infection in five working groups: (1) indications/associations, (2) diagnosis, (3) treatment, (4) prevention/gastric cancer and (5) H. pylori and the gut microbiota. The results of the individual working groups were presented for a final consensus voting that included all participants. Recommendations are provided on the basis of the best available evidence and relevance to the management of H. pylori infection in various clinical fields.

Proton Pump Inhibitors and Gastric Cancer

Concerns have been raised regarding the long-term use of proton pump inhibitors (PPIs) as an important risk factor for gastric cancer in clinical practice. PPIs can cause hypergastrinemia at clinical doses, and hypergastrinemia has been reported to induce malignant neoplasms in the stomach in previous animal studies. In humans, the proliferation of enterochromaffin-like (ECL) cells induced by hypergastrinemia is suspected as a potential mechanism of gastric cancer. Meanwhile, persistent Helicobacter pylori (H. pylori) infection causes gastric atrophic change, which itself is a major cause of gastric cancer, and it can further increase the risk of gastric cancer by strengthening corpus atrophy through interaction with PPIs. Recent epidemiologic studies have reported an important link between long-term PPI intake and gastric cancer risk even after successful eradication of H. pylori. However, due to the methodological limitations of observational clinical studies, the causal relationship is still not clear, and a recent big data-based study reported that long-term PPI use was not related to gastric cancer incidence. Taken together, despite the potential detrimental effects of PPIs, it is currently difficult to draw a definite conclusion about its association with gastric cancer. To minimize the possibility of gastric cancer in H. pylori-infected patients or precancerous lesions in long-term PPI users, long-term PPI administration should be limited to the minimum effective dose, and antibacterial treatment for H. pylori should be considered.

Use of Proton Pump Inhibitors vs Histamine 2 Receptor Antagonists for the Risk of Gastric Cancer: Population-Based Cohort Study

INTRODUCTION

Proton pump inhibitors (PPIs) are commonly prescribed medications. Long-term use of PPIs has been suspected to have a provocative effect on gastric cancer. This study was to determine the association between PPI vs histamine 2 receptor antagonist (H2RA) use and the risk of gastric cancer in a region where the risk of this malignancy is high.

METHODS

A population-based cohort study using the Korean National Health Insurance Services Database. The participants with first prescription of PPIs and H2RA with normal esophagogastroduodenoscopy finding from 2004 through 2015 were collected. Among them, 50% of participants were systematic stratified randomly sampled. There were 122,118 users of PPIs or H2RAs who use medication more than cumulative defined daily dose of 180 days. The users were followed up from long-term use threshold until gastric cancer, death from non-gastric cancer cause, gastric surgery, or study end (December 2017).

RESULTS

After calculating propensity score weights, we included 39,799 PPI and 38,967 H2RA users. Among the new PPI and H2RA users, we identified 411 cases of incident gastric cancer from 182,643 person-years of follow-up observation and 397 cases from 178,846 person-years of follow-up observation, respectively. Compared with H2RA users, PPI users did not experience significantly different gastric cancer incidence (adjusted hazard ratio, 1.01; 95% confidence interval, 0.88-1.16; P = 0.89). Sensitivity analyses confirmed that gastric cancer incidence did not differ between PPI and H2RA users.

DISCUSSION

In this large study, long-term treatment with PPIs vs H2RAs did not show higher risk of gastric cancer even in a high-risk region.

Influence of hypergastrinemia secondary to long-term proton pump inhibitor treatment on ECL cell tumorigenesis in human gastric mucosa

Proton pump inhibitor (PPI) therapy causes hypergastrinemia, which could promote the development and progression of neuroendocrine tumors (NETs). Concerns have been raised about the safety of long-term PPI use due to a possible increased risk of NETs. This study aimed to investigate the association between hypergastrinemia and the risk of NETs. Twenty outpatients presenting with serum gastrin levels greater than 400 pg/mL after long-term PPI treatment were registered in this study. Immunohistochemical analyses for chromogranin A (CgA), Ki67, gastrin and CCK/B gastrin receptor (CCKBR) were performed, and positive cell numbers were counted. There were no NET or gastric epithelial neoplasia cases observed among any of the 20 patients examined throughout the PPI treatment period. Histologically, ECL cell hyperplasia were shown in all patients. However, no relationship was found between serum gastrin levels and the number of CgA positive ECL cells. There was also no relationship between serum gastrin levels and the proportion of Ki67 positive cells or the density of CCKBR positive cells. The data indicate no relationship may exist between NETs and hypergastrinemia secondary to PPI treatment in patients having no, or mild, atrophic gastritis.

Pharmacological Effects and Toxicogenetic Impacts of Omeprazole: Genomic Instability and Cancer

Omeprazole (OME) is commonly used to treat gastrointestinal disorders. However, long-term use of OME can increase the risk of gastric cancer. We aimed to characterize the pharmacological effects of OME and to correlate its adverse effects and toxicogenetic risks to the genomic instability mechanisms and cancer-based on database reports. Thus, a search (till Aug 2019) was made in the PubMed, Scopus, and ScienceDirect with relevant keywords. Based on the study objective, we included 80 clinical reports, forty-six in vitro, and 76 in vivo studies. While controversial, the findings suggest that long-term use of OME (5 to 40 mg/kg) can induce genomic instability. On the other hand, OME-mediated protective effects are well reported and related to proton pump blockade and anti-inflammatory activity through an increase in gastric flow, anti-inflammatory markers (COX-2 and interleukins) and antiapoptotic markers (caspases and BCL-2), glycoprotein expression, and neutrophil infiltration reduction. The reported adverse and toxic effects, especially in clinical studies, were atrophic gastritis, cobalamin deficiencies, homeostasis disorders, polyp development, hepatotoxicity, cytotoxicity, and genotoxicity. This study highlights that OME may induce genomic instability and increase the risk of certain types of cancer. Therefore, adequate precautions should be taken, especially in its long-term therapeutic strategies and self-medication practices.

Long-term use of proton-pump inhibitors and risk of gastric cancer: a review of the current evidence

Gastric cancer remains one of the leading cancers in the world with a high mortality, particularly in East Asia. Helicobacter pylori infection accounts for the majority of the noncardia gastric cancers by triggering gastric inflammation and subsequent neoplastic progression. Eradication of H. pylori can reduce, but not totally eliminate, subsequent risk of developing gastric cancer. Proton-pump inhibitors (PPIs) are one of the most widely prescribed medications worldwide. With their profound gastric-acid suppression, there are concerns about a possible carcinogenic role in gastric cancer, due to induced hypergastrinemia, gastric atrophy and bacterial overgrowth in the stomach. While randomized clinical trials to establish causality between long-term PPI use and gastric cancer are lacking, current evidence based on observational studies suggests PPIs are associated with an increased gastric cancer risk. However, opinions on causality remain divergent due to unmeasured and possible residual confounding in various studies. Our recent study has showed that even after H. pylori eradication, long-term PPI use is still associated with an increased risk of gastric cancer by more than twofold. Hence, long-term PPIs should be used judiciously after considering individual's risk-benefit profile, particularly among those with history of H. pylori infection. Further well-designed prospective studies are warranted to confirm the potential role of PPIs in gastric cancer according to baseline gastric histology and its interaction with other chemopreventive agents like aspirin, statins and metformin.

Proton pump inhibitors (PPIs) may cause gastric cancer - clinical consequences

Recently, two epidemiological studies showed that long-term treatment with proton pump inhibitors (PPIs) increased the risk of gastric cancer. It is well known that hypergastrinemia predisposes to gastric neoplasia in animals as well as man. Recently a study showed that hypergastrinemic patients had an increased risk of gastric cancer when followed for about 25 years. It is likely that hypergastrinemia is the pathogenic factor for gastric carcinogenesis due to PPI. PPI are the only group of drugs that causes long-term hypergastrinemia in the doses used in a clinical setting. Due to the likely carcinogenic effect, PPIs should be used carefully. Moreover, since the carcinogenic effect of Helicobacter pylori (Hp) infection also may be mediated by an increase in gastrin, Hp should be eradicated whenever treatment with PPI is initiated. In peptic ulcer disease Hp eradication is the treatment of choice. Gastro-oesophageal reflux disease (GERD) is the most prevalent condition leading to long-term use of inhibitors of gastric acid secretion. Only in severe oesophagitis should the treatment be initiated by PPIs, whereas histamine-2 (H-2) blockers ought to be the initial option in most cases of GERD particularly since PPI treatment induces tolerance to H-2 blockers. In the cases where long-term PPI treatment is necessary, the dose should be adjusted by the determination of chromogranin A, which in a way reflects 24-h gastrin exposure. Finally, due to latency of neoplasia, the use of PPI must be very restricted in children and young adults.

Toxicity of long-term use of proton pump inhibitors in children

Proton pump inhibitor (PPI) use is becoming increasingly common. Although the toxicity profiles of PPIs are not well understood particularly in children, PPIs have been associated with increased risks of gastrointestinal and respiratory tract infection, vitamin B₁₂ deficiency, hypomagnesaemia, bone fractures, and rebound hyperacidity after discontinuation. Prescribers should take into account that PPI uses pose toxicity risks, which remain to be fully characterised in infants and children.

Proton-pump inhibitors: understanding the complications and risks

Proton-pump inhibitors (PPIs) are the most effective therapy for the full spectrum of gastric-acid-related diseases. However, in the past decade, a steadily increasing list of complications following long-term use of PPIs has been reported. Their potent acid-suppressive action induces several structural and functional changes within the gastric mucosa, including fundic gland polyps, enterochromaffin-like cell hyperplasia and hypergastrinaemia, which can be exaggerated in the presence of Helicobacter pylori infection. As discussed in this Review, most associations of PPIs with severe adverse events are not based on sufficient evidence because of confounding factors and a lack of plausible mechanisms. Thus, a causal relationship remains unproven in most associations, and further studies are needed. Awareness of PPI-associated risks should not lead to anxiety in patients but rather should induce the physician to consider the appropriate dosing and duration of PPI therapy, including long-term monitoring strategies in selected groups of patients because of their individual comorbidities and risk factors.

Fundic Gland Polyps in the Pediatric Population: Clinical and Histopathologic Studies

We retrospectively studied the clinical and histologic features of pediatric fundic gland polyps (FGPs) in 16 patients. FGPs had an endoscopic prevalence of 0.25% in 8527 pediatric gastric biopsies. Five patients had familial adenomatous polyposis (FAP). The median age of onset was 17.7 years in FAP and 17.3 years in sporadic patients. All syndromic patients were asymptomatic and FGPs were identified during surveillance for existing or concurrent colon polyps. They did not take antacids. In comparison, all 11 sporadic FGPs were identified during evaluation of symptomatic patients who had taken antacids (median duration 21 months). Syndromic FGPs can be multiple at single endoscopy and were more likely to recur, while sporadic FGPs were often single. None of the sporadic patients had recurrence of FGPs or a subsequent diagnosis of FAP during a median follow-up of 20.5 months. The dilated fundic glands were lined by parietal and chief cells only in a majority (22/41, 53.7%) of syndromic FGPs, while additional tall mucinous lining cells were found in all sporadic FGPs. Syndromic FGPs did not have parietal cell hypertrophy in the background oxyntic mucosa. Nuclear immunopositivity for beta-catenin was essentially absent in all the FGPs. In conclusion, FGPs were rare in pediatric patients. In syndromic patients, FGPs are asymptomatic and did not precede colon polyps. Prolonged antacid intake seems to be associated with development of sporadic FGPs. Cellular components of dilated fundic glands and background parietal cell hypertrophy can be useful features to eliminate concern for syndromic polyposis.

Chronic proton pump inhibition therapy in the diagnostic accuracy of serum pepsinogen I and gastrin concentrations to identify pernicious anaemia

BACKGROUND

Chronic use of proton pump inhibitors (PPIs) leads to increases in gastrin and pepsinogen-I serum concentrations.

AIM

To asses if chronic treatment with PPIs has an effect on serum gastrin and pepsinogen-I concentrations for the diagnosis of pernicious anaemia (PA).

MATERIALS AND METHODS

Serum gastrin and pepsinogen-I were measured in 38 patients with PA and 74 without PA (controls); 17/38 PA patients and 36/74 controls were treated with PPIs. Receiver Operating Curves (ROC) were used to compare diagnostic accuracy of gastrin and pepsinogen-I for PA in patients under chronic treatment with PPIs and in untreated patients.

RESULTS

PPI treatment increased pepsinogen-I in patients and in controls, while gastrin increased only in controls. In untreated patients, a pepsinogen-I <8.3ng/mL had 95.2% sensitivity and 100% specificity, whereas a gastrin >115pg/mL had 100% sensitivity and 92.11% specificity for PA diagnosis. In PPI-treated patients, a pepsinogen I<24.1ng/mL had a lower sensitivity (82.4%) but retained 100% specificity, however the best cut-off point for gastrin, 610pg/mL, had a very low sensitivity (58%).

CONCLUSIONS

PPI chronic treatment decreased the diagnostic accuracy for the studied biomarkers, particularly of gastrin. In PPI-treated patients, serum pepsinogen-I concentrations >24.1ng/mL allowed rejecting a PA diagnosis with 100% specificity.

Effective and safe proton pump inhibitor therapy in acid-related diseases - A position paper addressing benefits and potential harms of acid suppression

BACKGROUND

The introduction of proton pump inhibitors (PPIs) into clinical practice has revolutionized the management of acid-related diseases. Studies in primary care and emergency settings suggest that PPIs are frequently prescribed for inappropriate indications or for indications where their use offers little benefit. Inappropriate PPI use is a matter of great concern, especially in the elderly, who are often affected by multiple comorbidities and are taking multiple medications, and are thus at an increased risk of long-term PPI-related adverse outcomes as well as drug-to-drug interactions. Herein, we aim to review the current literature on PPI use and develop a position paper addressing the benefits and potential harms of acid suppression with the purpose of providing evidence-based guidelines on the appropriate use of these medications.

METHODS

The topics, identified by a Scientific Committee, were assigned to experts selected by three Italian Scientific Societies, who independently performed a systematic search of the relevant literature using Medline/PubMed, Embase, and the Cochrane databases. Search outputs were distilled, paying more attention to systematic reviews and meta-analyses (where available) representing the best evidence. The draft prepared on each topic was circulated amongst all the members of the Scientific Committee. Each expert then provided her/his input to the writing, suggesting changes and the inclusion of new material and/or additional relevant references. The global recommendations were then thoroughly discussed in a specific meeting, refined with regard to both content and wording, and approved to obtain a summary of current evidence.

RESULTS

Twenty-five years after their introduction into clinical practice, PPIs remain the mainstay of the treatment of acid-related diseases, where their use in gastroesophageal reflux disease, eosinophilic esophagitis, Helicobacter pylori infection, peptic ulcer disease and bleeding as well as, and Zollinger-Ellison syndrome is appropriate. Prevention of gastroduodenal mucosal lesions (and symptoms) in patients taking non-steroidal anti-inflammatory drugs (NSAIDs) or antiplatelet therapies and carrying gastrointestinal risk factors also represents an appropriate indication. On the contrary, steroid use does not need any gastroprotection, unless combined with NSAID therapy. In dyspeptic patients with persisting symptoms, despite successful H. pylori eradication, short-term PPI treatment could be attempted. Finally, addition of PPIs to pancreatic enzyme replacement therapy in patients with refractory steatorrhea may be worthwhile.

CONCLUSIONS

Overall, PPIs are irreplaceable drugs in the management of acid-related diseases. However, PPI treatment, as any kind of drug therapy, is not without risk of adverse effects. The overall benefits of therapy and improvement in quality of life significantly outweigh potential harms in most patients, but those without clear clinical indication are only exposed to the risks of PPI prescription. Adhering with evidence-based guidelines represents the only rational approach to effective and safe PPI therapy. Please see related Commentary: doi: 10.1186/s12916-016-0724-1 .

Widespread use of gastric acid inhibitors in infants: Are they needed? Are they safe?

Gastroesophageal reflux is a common phenomenon in infants, but the differentiation between gastroesophageal reflux and gastroesophageal reflux disease can be difficult. Symptoms are non-specific and there is increasing evidence that the majority of symptoms may not be acid-related. Despite this, gastric acid inhibitors such as proton pump inhibitors are widely and increasingly used, often without objective evidence or investigations to guide treatment. Several studies have shown that these medications are ineffective at treating symptoms associated with reflux in the absence of endoscopically proven oesophagitis. With a lack of evidence for efficacy, attention is now being turned to the potential risks of gastric acid suppression. Previously assumed safety of these medications is being challenged with evidence of potential side effects including GI and respiratory infections, bacterial overgrowth, adverse bone health, food allergy and drug interactions.

Systematic review with meta-analysis: fundic gland polyps and proton pump inhibitors

BACKGROUND

A causal association between proton pump inhibitor (PPI) use and fundic gland polyps has been suggested, but the data are conflicting.

AIM

To clarify the relationship through a meta-analysis of the existing data.

METHODS

A systematic retrieval and selection of records was performed. The main inclusion criteria were original studies reporting the prevalence of fundic gland polyps in PPI users or the reverse, compared to controls. Key outcomes were the odds ratios (OR) for fundic gland polyp prevalence in association with PPI use, prevalence of PPI use amongst subjects with fundic gland polyps and fundic gland polyp prevalence among PPI users. Statistical analysis was performed using Mix 2.0 Pro.

RESULTS

The initial search using electronic databases and manual searching retrieved 339 peer-reviewed articles and abstracts. Twenty articles met all inclusion and exclusion criteria, with a total of 40 218 subjects included. The meta-analysis of 12 studies revealed an increase in fundic gland polyps amongst PPI users compared to controls (OR 2.46, 95% CI 1.42-4.27, P = 0.001), particularly among individuals taking PPIs for at least 6 months (OR: 4.71, 95% CI 2.22-9.99, P < 0.001) or 12 months (OR: 5.32, 95% CI 2.58-10.99, P < 0.001).

CONCLUSIONS

Proton pump inhibitor usage is associated with a significantly increased prevalence of fundic gland polyps, and there is a trend for this to increase with longer length of PPI exposure. However, the meta-analysis is limited mainly to cohort studies.

Safety of proton pump inhibitors and risk of gastric cancers: review of literature and pathophysiological mechanisms

INTRODUCTION

Despite being an overall safe drug, several long-term adverse effects are associated with proton pump inhibitors (PPIs). The link between PPI use and gastric neuroendocrine tumors (NETs), gastric adenocarcinomas and Barrett's esophagus progression gastric cancers has been investigated due to PPI-induced hypergastrinemia.

AREAS COVERED

The pathophysiological mechanisms underlying PPI exposure and gastric NETs, gastric adenocarcinomas and Barrett's esophagus progression are discussed. The quality of randomized control studies, cohort studies and case reports investigating the link between gastric cancers and PPIs are examined. Recommendations for clinicians are provided.

EXPERT OPINION

PPIs cause a hypergastrinemic state, increasing enterochromaffin-like cell dysplasia and risk of gastric NET development, increasing gastritis severity in the context of Helicobacter pylori infection, and progression of carcinogenesis in a certain predisposed subset of Barrett's esophagus patients. There are case reports of PPI-induced gastric NETs and adenocarcinomas as consequences of these effects. In pernicious anemia and chronic gastritis, clinicians should be aware of potential increased risk of gastric NET development with chronic PPI use in these patients. Eradication status of H. pylori prior to commencing long-term PPI therapy should be established to reduce the risk of severe atrophic gastritis and development of gastric dysplasia.

Systematic review: the effects of long-term proton pump inhibitor use on serum gastrin levels and gastric histology

BACKGROUND

Proton pump inhibitors (PPIs) have a well-established safety profile. However, concerns have been raised about a potential relationship between PPI-induced hypergastrinaemia and the development of enterochromaffin-like (ECL) cell hyperplasia, neuroendocrine tumours and gastric cancer during long-term therapy.

AIM

To review the effects of long-term PPI use on serum gastrin levels and gastric histopathology.

METHODS

A systematic literature search was conducted in PubMed on 21 April 2015 to identify studies reporting the effects of long-term (defined as >3 years) PPI use on gastrin levels and gastric histopathology.

RESULTS

A total of 16 studies (1920 patients) met the inclusion criteria. During long-term PPI therapy, mean gastrin levels rose to one to three times the upper limit of the normal range (~100 pg/mL), and an increased prevalence of ECL cell hyperplasia was observed (+7.8-52.0%). Helicobacter pylori-positive patients had a significantly increased risk of developing ECL linear/micronodular hyperplasia compared with H. pylori-negative patients [OR: 2.45 (95% CI: 1.47-4.10), P = 0.0006]; however, no evidence of neoplastic changes was found. The risk of corpus atrophy was markedly higher in H. pylori-positive patients than in H. pylori-negative patients [OR: 11.45 (95% CI: 6.25-20.99), P < 0.00001]. Not a single case of gastric adenocarcinoma was found.

CONCLUSIONS

Long-term PPI therapy induced moderate hypergastrinaemia in most patients and an increased prevalence of ECL cell hyperplasia. H. pylori-positive patients receiving long-term PPI therapy were exposed to a higher risk of corpus atrophy than H. pylori-negative patients. No neuroendocrine tumours or gastric cancers were found.

Rationale for a Helicobacter pylori Test and Treatment Strategy in Gastroesophageal Reflux Disease

Conflicting data have been published on the effect of long-term proton pump inhibitor therapy on the gastric mucosa in Helicobacter pylori-infected subjects. In this article, the available data are reviewed and a rationale is offered for why infected patients who are about to commence long-term proton pump inhibitor therapy should be offered eradication therapy.

Gastric neuroendocrine neoplasms and proton pump inhibitors: fact or coincidence?

OBJECTIVE

Reporting on three cases of gastric neuroendocrine tumors (g-NETs) in patients taking long-term proton pump inhibitors (PPIs). These tumors are not classifiable considering current criteria. g-NETs are currently grouped as: types 1 and 2, related to hypergastrinemia due to chronic atrophic gastritis and Zollinger-Ellison syndrome respectively, and type 3, normogastrinemic and more aggressive. Although the g-NETs onset in patients taking PPIs is biologically plausible, only a few cases have been reported so far.

MATERIALS AND METHODS

From January 2005 to July 2014, 31 g-NETs were referred to our Unit: 24 (77%), one (3%) and three (10%) resulted types 1, 2 and 3, respectively. Three cases (10%) did not meet the current classification criteria.

RESULTS

The three patients were administered long-term PPIs for gastro-esophageal reflux disease. Patient 1: a 78-year-old man, with a 4-mm well-differentiated g-NET (Ki-67<1%) and marked hypergastrinemia. Patient 2: a 58-year-old man affected by a 6-mm well-differentiated (Ki-67 = 4%) g-NET, with normal gastrin levels. Patients 3: a 67-year-old woman with an 18-mm well-differentiated g-NET (Ki-67 <2%), with mild hypergastrinemia. In the three patients, histology and pertinent blood tests excluded chronic atrophic gastritis, Helicobacter pylori infection or Zollinger-Ellison syndrome. The first two patients underwent endoscopic polypectomy; in the third case total gastrectomy was performed. Further clinical, endoscopic and imaging follow-up did not show any g-NET recurrence.

CONCLUSIONS

The present data point to the existence and epidemiological relevance of g-NETs associated with PPIs intake. These neoplasms are not included in the current classification, thus their treatment and follow-up have not been established.

Long-term safety of proton pump inhibitor therapy assessed under controlled, randomised clinical trial conditions: data from the SOPRAN and LOTUS studies

BACKGROUND

Control of chronic gastro-oesophageal reflux disease may be achieved either by anti-reflux surgery (ARS) or by long-term medical therapy with proton pump inhibitors (PPIs). The primary efficacy results of the SOPRAN study, comparing long-term omeprazole use with open ARS, and the LOTUS study, comparing long-term esomeprazole use with laparoscopic ARS, have been reported. A secondary objective of these studies was to address the long-term safety of these respective therapeutic strategies and thereby provide a valid scientific platform for assessing long-term PPI safety.

AIM

To assess the safety of long-term PPI therapy with omeprazole and esomeprazole through analyses of data from the randomised SOPRAN and LOTUS studies.

METHODS

Safety data were collected from patients during the 12-year period of the SOPRAN study (n = 298) and the 5-year period of the LOTUS study (n = 514). Reported serious adverse events (SAEs) and changes in laboratory variables were analysed.

RESULTS

Across both studies, SAEs were reported at a similar frequency in the PPI and ARS treatment groups. Taking the time frames into consideration, the number of fatal SAEs in the two studies was low in both treatment groups. Laboratory results, including routine haematology and tests for liver enzymes, electrolytes, vitamin D, vitamin B12 , folate and homocysteine, showed no clinically relevant changes over time. As expected, gastrin and chromogranin A were elevated in the PPI groups, with the greatest increases observed in the first year.

CONCLUSION

No major safety concerns arose during 5-12 years of continuous PPI therapy. (ClinicalTrials.gov: NCT00251927 and NCT00256737).

Is antisecretory therapy after pancreatoduodenectomy necessary? Meta-analysis and contemporary practices of pancreatic surgeons

BACKGROUND

Marginal ulcer (MU) is a well-described complication of pancreatoduodenectomy (PD) whose incidence remains unclear. Gastric antisecretory medications likely attenuate the risk of marginal ulceration after PD; however, the true relationship between antisecretory medication and marginal ulceration after PD is not precisely known. The aims of this study were to document the incidence of MU after PD, identify any relationship between MU and gastric antisecretory medication, and survey current practice of MU prophylaxis among experienced pancreatic surgeons.

METHODS

the MEDLINE, EMBASE, Cochrane Central Registrar of Controlled Trials, and Cochrane Database of Systematic Reviews databases were searched from their inception to May 2014 for abstracts documenting ulceration after pancreatoduodenectomy. Two reviewers independently graded abstracts for inclusion in this review. Contemporary practice was assessed through a four-question survey distributed globally to 200 established pancreatic surgeons.

RESULTS

After a review of 208 abstracts, 54 studies were graded as relevant. These represented a cohort of 212 patients with marginal ulcer after PD (n = 4794). A meta-analysis of the included references shows mean incidence of ulceration after PD of 2.5% (confidence interval (CI) 1.8-3.2%) with a median time to diagnosis of 15.5 months. Pylorus preservation was associated with a MU rate of 2.0% (CI 1.0-2.9%), while "classic" PD procedures report an overall rate of 2.6% (CI 1.6-3.6%). Documented use of postoperative antisecretory medication was associated with a reduced rate of 1.4% (CI 0.1-1.7%). One hundred forty-four of 200 (72%) surveys were returned, from which it was determined that 92% of pancreatic surgeons have dealt with this complication, and 86% routinely prescribe prophylactic antisecretory medication after PD.

CONCLUSIONS

The incidence of MU after PD is 2.5% with a median time to occurrence of 15.5 months postoperatively. Gastric antisecretory medication prescription may affect the incidence of MU. The majority of pancreatic surgeons surveyed have encountered MU after PD; most (86%) routinely prescribe prophylactic gastric antisecretory medication.

Physiology and pathogenesis of gastroesophageal reflux disease

Gastroesophageal reflux disease (GERD) is one of the most common problems treated by primary care physicians. Almost 20% of the population in the United States experiences occasional regurgitation, heartburn, or retrosternal pain because of GERD. Reflux disease is complex, and the physiology and pathogenesis are still incompletely understood. However, abnormalities of any one or a combination of the three physiologic processes, namely, esophageal motility, lower esophageal sphincter function, and gastric motility or emptying, can lead to GERD. There are many diagnostic and therapeutic approaches to GERD today, but more studies are needed to better understand this complex disease process.

Long-term effect on symptoms and quality of life of maintenance therapy with esomeprazole 20 mg daily: a post hoc analysis of the LOTUS trial

OBJECTIVE

To assess the long-term effect on symptoms and quality of life of esomeprazole 20 mg once daily, a recommended dose for maintenance therapy of gastroesophageal reflux disease (GERD).

RESEARCH DESIGN AND METHODS

This is a post hoc analysis of 5 year data from patients in the LOTUS trial (ClinicalTrials.gov identifier: NCT00251927) who were randomized to esomeprazole 20 mg once daily. All participants had chronic, symptomatic GERD responsive to treatment. Gastrointestinal symptoms were assessed by physicians and by using patient-reported outcome instruments. Investigations included gastrointestinal endoscopy (with biopsy sampling), 24 hour esophageal pH monitoring and laboratory measurements.

RESULTS

In total, 157 of 256 patients randomized to esomeprazole 20 mg once daily remained on this dose until the end of follow-up or study discontinuation, whereas 99 patients had their dose increased because of inadequate symptom control (of these, 29 subsequently returned to the allocated dose). On logistic regression, a long objectively defined GERD history, smoking, female sex, absence of Helicobacter pylori infection and high supine baseline acid reflux into the esophagus were associated with an increased likelihood of requiring dose escalation to esomeprazole 40 mg daily (all p < 0.05). Symptoms were fairly stable and quality of life was normal throughout follow-up in patients remaining on esomeprazole 20 mg once daily, with no more than mild symptom severity, and mean (standard deviation) percentage time with intraesophageal pH <4 was reduced from 10.7 (10.7) pre-randomization to 6.3 (10.2) at 6 months and 4.9 (7.3) at 5 years. The number of serious adverse events was low (0.079 per patient per year).

LIMITATIONS

Post hoc analysis with no control group.

CONCLUSIONS

Esomeprazole at a maintenance dose of 20 mg once daily offers effective long-term treatment for chronic GERD in patients initially responsive to the medication, with durable symptom control and sustained reductions in intraesophageal acid exposure.

Long-term proton pump inhibitor (PPI) use and the development of gastric pre-malignant lesions

BACKGROUND

Proton pump inhibitors (PPIs) are the most effective drugs to reduce gastric acid secretion. PPIs are one of the most commonly prescribed classes of medications worldwide. Apart from short-term application, maintenance therapy with PPIs is recommended and increasingly used in certain diseases, such as Zollinger-Ellison syndrome and gastro-oesophageal reflux disease, especially for people with erosive oesophagitis or Barrett's oesophagus. Although PPIs are generally safe, their efficacy and safety of long-term use remains unclear. The question of whether the long-term use of PPIs could promote the development of gastric pre-malignant lesions has been widely investigated, but results are inconsistent. Limited insight on this problem leads to a dilemma in decision making for long-term PPI prescription.

OBJECTIVES

To compare the development or progression of gastric pre-malignant lesions, such as atrophic gastritis, intestinal metaplasia, enterochromaffin-like (ECL) cell hyperplasia, and dysplasia, in people taking long-term (six months or greater) PPI maintenance therapy.

SEARCH METHODS

We searched the following databases (from inception to 6 August 2013): the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, and CINAHL. In addition, we searched the reference lists of included trials and contacted experts in the field.

SELECTION CRITERIA

We searched for randomised controlled trials (RCTs) in adults (aged 18 years or greater) concerning the effects of long-term (six months or greater) PPI use on gastric mucosa changes, confirmed by endoscopy or biopsy sampling (or both).

DATA COLLECTION AND ANALYSIS

Two review authors independently performed selection of eligible trials, assessment of trial quality, and data extraction. We calculated odds ratios (OR) for analysis of dichotomous data and mean differences for continuous data, with 95% confidence intervals (CI).

MAIN RESULTS

We included seven trials (1789 participants). Four studies had high risk of bias and the risk of bias in the other three trials was unclear. In addition, it was difficult to assess possible reporting bias. We pooled 1070 participants from four RCTs to evaluate corporal atrophy development revealing an insignificantly increased OR of 1.50 (95% CI 0.59 to 3.80; P value = 0.39; low-quality evidence) for long-term PPI users relative to non-PPI users. In five eligible trials, corporal intestinal metaplasia was assessed among 1408 participants, also with uncertain results (OR 1.46; 95% CI 0.43 to 5.03; P value = 0.55; low-quality evidence). However, by pooling data of 1705 participants from six RCTs, our meta-analysis showed that participants with PPI maintenance treatment were more likely to experience either diffuse (simple) (OR 5.01; 95% CI 1.54 to 16.26; P value = 0.007; very-low-quality evidence) or linear/micronodular (focal) ECL hyperplasia (OR 3.98; 95% CI 1.31 to 12.16; P value = 0.02; low-quality evidence) than controls. No participant showed any dysplastic or neoplastic change in any included studies.

AUTHORS' CONCLUSIONS

There is presently no clear evidence that the long-term use of PPIs can cause or accelerate the progression of corpus gastric atrophy or intestinal metaplasia, although results were imprecise. People with PPI maintenance treatment may have a higher possibility of experiencing either diffuse (simple) or linear/micronodular (focal) ECL cell hyperplasia. However, the clinical importance of this outcome is currently uncertain.

Pharmacokinetic evaluation of esomeprazole for the treatment of gastroesophageal reflux disease

INTRODUCTION

Proton pump inhibitors (PPIs) are widely used for the treatment of acid-related diseases such as gastroesophageal reflux disease (GERD). They are recommended by the American College of Gastroenterology for healing erosive esophagitis (EO) and as long-term treatment in patients with healed EO. The available PPIs differ somewhat in their pharmacokinetics and clinical properties, but whether these differences are of clinical relevance is a matter of debate. Some safety concerns have been raised with the use of PPIs, mostly an increased incidence of infectious diseases such as community-acquired pneumonia or Clostridium difficile diarrhea.

AREAS COVERED

This article explores the results of clinical studies on the pharmacokinetics and pharmacodynamics of esomeprazole , as well as on its clinical efficacy to manage patients with GERD.

EXPERT OPINION

GERD is a public health concern as its worldwide incidence and associated complications are increasing alongside the exponentially increasing problem of obesity. PPIs are the first pharmacological option because of their efficacy and overall positive risk-to-benefit ratio. Improved efficacy with the use of stereospecific isomers of PPIs, such as esomeprazole, has not yet been convincingly demonstrated. Nevertheless, because of individual experience with former treatment, some patients may report better symptom control when treated with a specific PPI rather than with others.

Gastric carcinoid in the absence of atrophic body gastritis and with low Ki67 index: a clinical challenge

BACKGROUND

Gastric carcinoids (GCs) represent 23% of all digestive neuroendocrine tumors (NETs). They can be distinguished into three types: type I (in the presence of atrophic body gastritis, ABG), type II (in the presence of Zollinger-Ellison/multiple endocrine neoplasia type I syndrome), type III (sporadic carcinoids, without any background pathology).

AIM

To describe a case of undetermined type of GCs in an Italian referral center for NETs and its prevalence among GCs during a 6-year period.

RESULTS

In a case series of 16 GCs seen at our unit between 2007 and 2012, 14 (83.3%) patients had type I carcinoid and 1 patient (6.2%) had type III carcinoid. One patient did not accomplish to the actual classification criteria. This patient had a well-differentiated carcinoid with low Ki67, but multiple gastric biopsies performed at 3-year follow-up gastroscopies excluded the presence of ABG. The patient had fundic cystic polyps, suggesting long-term use of proton pump inhibitors, possibly associated with GCs.

CONCLUSIONS

This case shows that a GC may occur in the absence of ABG and with low Ki67 index, making classification according to actual criteria difficult. Further studies are needed to better understand the occurrence of this particular type of GCs.

Long-term follow up in patients with gastroesophageal reflux disease with specific emphasis on reflux symptoms, use of anti-reflux medication and anti-reflux surgery outcome: a retrospective study

BACKGROUND

Various treatment modalities are currently being used in patients with gastroesophageal reflux disease (GERD); however, long-term outcome is not clear. The aim is to evaluate long-term results of GERD treatments with regard to reflux symptoms, use of anti-reflux medication and anti-reflux surgery outcome.

METHODS

Patients who had undergone 24-h pH monitoring for reflux symptoms between January 2002 and March 2012 were invited to fill out the Reflux Disease Questionnaire (RDQ) and a general questionnaire. Patients with and without anti-reflux surgery were compared using multiple linear and logistic regression models.

RESULTS

In total, 1027 of 2190 included patients (47%) returned the questionnaires. After exclusion due to predefined criteria, 477 patients were analyzed. Median total RDQ score was 18 points (10.2% symptom-free) in the conservative group (n = 304) and 10 points (31.2% symptom-free) in the surgical group (n = 173) after a mean follow up of 5.1 years. Daily proton pomp inhibitor (PPI) use was higher in the conservative group than in the surgical group (80.9% vs. 51.4%, p = 0.000). Linear regression analysis showed an association between RDQ scores and anti-reflux surgery (β = -5.477, p = 0.001) and male gender (β = -4.306, p = 0.006). Logistic regression analyses showed that daily PPI use was lower in patients who underwent anti-reflux surgery (odds ratio [OR] = 0.24, p = 0.000), while it increased with age (OR = 1.03, p = 0.000).

CONCLUSIONS

There is still a high prevalence of typical reflux symptoms and daily PPI use in GERD patients after >5 years of follow up. Male patients and patients who had undergone anti-reflux surgery were more often asymptomatic. Daily PPI use was lower after anti-reflux surgery, while it increased with age.

Qualitative analysis of anatomopathological changes of gastric mucosa due to long term therapy with proton pump inhibitors: experimental studies x clinical studies

INTRODUCTION

For a few decades the long-term use of proton pump inhibitors has had wide application in the treatment of several gastrointestinal diseases. Since then, however, several studies have called attention to the possible development of anatomical and pathological changes of gastric mucosa, resulting from the long term use of this therapeutic modality. Recent experimental and clinical studies suggest that these changes have connection not only to the development of precancerous lesions, but also of gastric tumors.

OBJECTIVE

To present a qualitative analysis of anatomical and pathological changes of gastric mucosa resulting from the long-term use of proton pump inhibitors.

METHOD

The headings used were: proton pump inhibitors, precancerous lesions and gastric neoplasms for a non systematic review of the literature, based on Medline, Lillacs and Scielo. Twelve articles were selected from clinical (9) and experimental (3) studies, for qualitative analysis of the results.

RESULTS

The gastric acid suppression by high doses of proton pump inhibitors induces hypergastrinemia and the consequent emergence of neuroendocrine tumors in animal models. Morphological changes most often found in these experimental studies were: enterochromaffin-like cell hyperplasia, neuroendocrine tumor, atrophy, metaplasia and adenocarcinoma. In the studies in humans, however, despite enterochromaffin-like cell hyperplasia, the other effects, neuroendocrine tumor and gastric atrophy, gastric metaplasia and or adenocarcinoma, were not identified.

CONCLUSION

Although it is not possible to say that the long-term treatment with proton pump inhibitors induces the appearance or accelerates the development of gastric cancer in humans, several authors have suggested that prolonged administration of this drug could provoke the development of gastric cancer. Thus, the evidence demonstrated in the animal model as well as the large number of patients who do or will do a long-term treatment with proton pump inhibitors, justifies the maintenance of this important line of research.

Gastric secretion

PURPOSE OF REVIEW

The review summarizes the past year's literature, basic science and clinical, regarding the neural, paracrine, hormonal, and intracellular regulation of gastric acid secretion.

RECENT FINDINGS

Gastric acid facilitates the digestion of protein as well as the absorption of iron, calcium, vitamin B(12), and certain medications (e.g. thyroxin). It also kills ingested microorganisms and prevents bacterial overgrowth, enteric infection, and possibly spontaneous bacterial peritonitis. Stimulants of acid secretion include histamine, gastrin, acetylcholine, and ghrelin. Inhibitors include somatostatin, nefstatin-1, interleukin-11, and calcitonin gene-related peptide. Helicobacter pylori stimulates or inhibits acid secretion depending upon the time course of infection and the area of the stomach predominantly infected. Acute infection activates calcitonin gene-related peptide sensory neurons coupled to inhibition of histamine and acid secretion. Serum chromogranin A, a marker for neuroendocrine tumors, is elevated in patients taking proton pump inhibitors.

SUMMARY

Progress continues in our understanding of the regulation of gastric acid secretion in health and disease, as well as the function of gastric neuroendocrine cells. The recognition that gastrin is not only a secretagogue but also a trophic hormone has led to new research into the role of gastrin and its receptor (cholecystokinin-2 receptor) in carcinogenesis and the development of cholecystokinin-2 receptor antagonists.

Complications of gastro-oesophageal reflux disease

Gastro-oesophageal reflux disease (GORD) is on the rise with more than 20% of the western population reporting symptoms and is the most common gastrointestinal disorder in the United States. This increase in GORD is not exactly clear but has been attributed to the increasing prevalence of obesity, changing diet, and perhaps the decreasing prevalence of H. pylori infection. Complications of GORD could be either benign or malignant. Benign complications include erosive oesophagitis, bleeding and peptic strictures. Premalignant and malignant lesions include Barrett's metaplasia, and oesophageal cancer. Management of both the benign and malignant complications can be challenging. With the use of proton-pump inhibitors, peptic strictures (i.e., strictures related to reflux) have significantly declined. Several aspects of Barrett's management remain controversial including the stage in the disease process which needs to be intervened, type of the intervention and surveillance of these lesions to prevent development of high grade dysplasia and oesophageal adenocarcinoma.