Associations among Gastric Juice pH, Atrophic Gastritis, Intestinal Metaplasia and Helicobacter pylori Infection

Molecular characterization and phylogenetic analysis of babA gene of Helicobacter pylori isolated from Indian patients with gastrointestinal diseases

INTRODUCTION

Outer membrane protein (OMP) of Helicobacter pylori (H. pylori) i.e., blood group antigen binding adhesin (babA) is responsible for the attachment of H. pylori in the gastric epithelium. Its adherence is causative for gastric pathology such as gastritis, peptic ulcer disease (PUD), or digestive tract disorders like erosive reflux disease (ERD) and (NERD) non-erosive reflux disease and together called Gastroesophageal reflux disease (GERD). BabA manifests rapid and varied selection via substitution of amino acid in its Leb-carbohydrate binding domain (CBD) which enables better binding preferences for distinct human populations and ABO blood group phenotypes. The positive evolutionary selection of the pathogenic factor of this genetically diverse bacterium has enabled it to adapt to the host gastric environment. Analyzing the association of virulent genes (cagA, vacA) and babA will help us better understand bacteria's pathogenicity.

METHOD

109 H. pylori strains from patients with distinct gastrointestinal diseases were genotyped using Polymerase Chain Reaction(PCR) for cagA, vacA, and babA followed by Sanger sequencing and phylogenetic analysis.

RESULT

In the babA + ve genotype, a statistically significant association with p = 0.04 and < 0.0001 is seen in gastritis and ERD respectively. A significant association of genotype vacAs1m2 (p = 0.0002) was seen in gastritis, vacAs1m1 (p = 0.02) in NERD, vacAs1m1 (p < 0.0001) and vacAs1m2 (p = 0.002) in ERD. This relationship helps to detect gastritis or ERD where BabA gene can be used as an independent marker for detecting their presence.

CONCLUSION

The appearance of variants within distinct disease categories is due to local genetic variation.

Identification of Autoantigens in Pediatric Gastric Juices

Purpose

This study aimed to investigate the presence of autoantigens in the gastric juices of children.

Methods

Gastric juice and serum samples were obtained from 53 children <15 years of age who underwent gastric endoscopy. Among these, 8, 22, and 23 participants were in the age groups 0-5, 6-10, and 11-15 years, respectively. These samples were analyzed using two-dimensional electrophoresis (2-DE), immunoblot analysis, and matrix-assisted laser desorption ionization-time of-flight mass spectrometry. Furthermore, we reviewed the histopathological findings and urease test results and compared them with the results of 2-DE and immunoblot analysis.

Results

There were no statistically significant differences in urease test positivity, grades of chronic gastritis, active gastritis, or Helicobacter pylori infiltration of the antrum and body among the three age groups. Three distinct patterns of gastric juice were observed on 2-DE. Pattern I was the most common, and pattern III was not observed below the age of 5 years. Histopathological findings were significantly different among active gastritis (p=0.037) and H. pylori infiltration (p=0.060) in the gastric body. The immunoblots showed large spots at an approximate pH of 3-4 and molecular weights of 31-45 kDa. These distinct, large positive spots were identified as gastric lipase and pepsin A and C.

Conclusion

Three enzymes, which are normally secreted under acidic conditions were identified as autoantigens. Further investigation of the pathophysiology and function of autoantigens in the stomach is required.

Global knowledge mapping and emerging trends in Helicobacter pylori-related precancerous lesions of gastric cancer research: A bibliometric analysis from 2013 to 2023

Helicobacter pylori (H pylori) infection is a crucial element in chronic gastritis progression towards precancerous lesions of gastric cancer (PLGC) formation and, potentially, gastric cancer; however, screening for and eliminating H pylori has several challenges. This study aimed to assess the present research status, prominent themes, and frontiers of H pylori-related PLGC and to provide impartial evaluations of the developmental trends in this domain. This study extracted articles and review papers concerning H pylori-related PLGC published from 2013 to 2023 from the Web of Science Core Collection. The data was analyzed and visualized using VOSviewer and CiteSpace. The study encompassed 1426 papers, with a discernible upward trend in publications between 2013 and 2023. China emerged as the most productive country, whereas the United States exerted the greatest influence. Baylor College of Medicine was the most prolific institution. World Journal of Gastroenterology featured the highest number of published papers, whereas Gastroenterology was the most frequently cited journal. Kim N. from South Korea was the most prolific author. Co-cited literature pertained to various aspects such as gastritis classification, H pylori infection management, gastric cancer prevention, and managing patients with PLGC. Future research will focus on the Kyoto classification, cancer incidence, and gastric intestinal metaplasia. The results of this study indicate a persistent increase in attention directed toward H pylori-associated PLGC. The research emphasis has transitioned from molecular mechanisms, epidemiology, monitoring, and diagnosis to clinical prevention and treatment methodologies. The forthcoming research direction in this area will concentrate on controlling and preventing malignant PLGC transformation.

Proton Pump Inhibitor Pantoprazole Modulates Intestinal Microbiota and Induces TLR4 Signaling and Fibrosis in Mouse Liver

Proton pump inhibitors (PPIs) are one of the most prescribed drugs around the world. PPIs induce microbiota modulation such as obesity both in humans and in animal models. However, since PPIs can induce microbiota modulation despite the absence of a high-fat diet or weight gain, it is an interesting model to correlate microbiota modulation with the establishment of non-alcoholic fatty liver disease (NAFLD). We investigated the effect of pantoprazole treatment on TLR4 signaling and liver histology in C57BL/6J mice for 60 days, trying to correlate microbiota modulation with some aspects of liver injury. We performed glucose (GTT) and insulin (ITT) tolerance tests, serum lipopolysaccharide (LPS) dosage, liver histology, liver and intestine extraction for Western blot and qPCR. Fecal microbiota were investigated via metagenomics. Chronic treatment with pantoprazole induced microbiota modulation and impaired ileum barrier integrity, without an association with insulin resistance. Furthermore, increased circulating LPS and increased Toll-like receptor 4 (TLR4) and TGFβ downstream signaling may have an important role in the development of the observed liver microvesicular steatosis and fibrosis. Finally, this model of PPI-induced changes in microbiota might be useful to investigate liver microvesicular steatosis and fibrosis.

Deoxycholic acid induces gastric intestinal metaplasia by activating STAT3 signaling and disturbing gastric bile acids metabolism and microbiota

Intestinal metaplasia (IM) is the inevitable precancerous stage to develop intestinal-type gastric cancer (GC). Deoxycholic acid (DCA) is the main bile acid (BA) component of duodenogastric reflux and has shown an increased concentration during the transition from chronic gastritis to IM associated with continued STAT3 activation. However, the mechanisms underlying how DCA facilitates IM in the gastric epithelium need exploration. We evaluated IM and bile reflux in corpus tissues from 161 subjects undergoing GC screening. Cell survival and proliferation, proinflammatory cytokine expression and TGR5/STAT3/KLF5 axis activity were measured in normal human gastric cells, cancer cells, and organoid lines derived from C57BL/6, FVB/N and insulin-gastrin (INS-GAS) mice treated with DCA. The effects of DCA on IM development were determined in INS-GAS mice with long-term DCA supplementation, after which the gastric bacterial and BA metabolic profiles were measured by 16S rRNA gene sequencing and LC-MS. We revealed a BA-triggered TGR5/STAT3/KLF5 pathway in human gastric IM tissues. In gastric epithelial cells, DCA promoted proliferation and apoptotic resistance, upregulated proinflammatory cytokines and IM markers, and facilitated STAT3 phosphorylation, nuclear accumulation and DNA binding to the KLF5 promoter. DCA triggered STAT3 signaling and the downstream IM marker KLF5 in mouse gastric organoids in vitro and in vivo. In INS-GAS mice, DCA promoted the accumulation of serum total BAs and accelerated the stepwise development of gastric IM and dysplasia. DCA induced gastric environmental alterations involving abnormal BA metabolism and microbial dysbiosis, in which the Gemmobacter and Lactobacillus genera were specifically enriched. Lactobacillus genus enrichment was positively correlated with increased levels of GCA, CA, T-α-MCA, TCA and β-MCA in DCA-administrated INS-GAS mice. DCA promotes nuclear STAT3 phosphorylation, which mediates KLF5 upregulation associated with gastric inflammation and IM development. DCA disturbs the gastric microbiome and BA metabolism homeostasis during IM induction.

Effect of invasive mechanical ventilation on the diversity of the pulmonary microbiota

Pulmonary microbial diversity may be influenced by biotic or abiotic conditions (e.g., disease, smoking, invasive mechanical ventilation (MV), etc.). Specially, invasive MV may trigger structural and physiological changes in both tissue and microbiota of lung, due to gastric and oral microaspiration, altered body posture, high O2 inhalation-induced O2 toxicity in hypoxemic patients, impaired airway clearance and ventilator-induced lung injury (VILI), which in turn reduce the diversity of the pulmonary microbiota and may ultimately lead to poor prognosis. Furthermore, changes in (local) O2 concentration can reduce the diversity of the pulmonary microbiota by affecting the local immune microenvironment of lung. In conclusion, systematic literature studies have found that invasive MV reduces pulmonary microbiota diversity, and future rational regulation of pulmonary microbiota diversity by existing or novel clinical tools (e.g., lung probiotics, drugs) may improve the prognosis of invasive MV treatment and lead to more effective treatment of lung diseases with precision.

Levothyroxine treatment and gastric juice pH in humans: the proof of concept

PURPOSE

Despite the absorption of oral thyroxine (T4) occurs in the small bowel, several patients with gastric disorders show an increased need for T4. In vitro evidence suggested that medium pH variations interfere with T4 dissolution. This study was aimed at finding the proof of concept of a direct relationship between the minimal effective dose of T4 and the actual gastric juice pH.

PATIENTS AND METHODS

Among 311 consecutively thyroxine-treated patients, 61 bearing Hashimoto's thyroiditis (52 F/9 M; median age = 51 years) who complained persistent dyspepsia and/or upper abdominal symptoms following a noninvasive workup for gastrointestinal disorders, underwent EGDS with multiple biopsies and gastric juice pH measurement. All patients accepted to take thyroxine in fasting conditions, abstaining from eating or drinking for one hour.

RESULTS

Thyroxine requirement increased along with the rising gastric pH (ρ = 0.4229; p = 0.0007). A multivariate analysis revealed that gastric pH was, beside body mass index, the far more important independent variable in determining the effective dose of T4 (p = 0.001). The ROC curve revealed that the pH threshold for an increased thyroxine requirement was at 2.28, being the AUC by 78%. Subdividing patients by the histologic findings, it appeared a significant increase (p = 0.0025) along with the progressive damage of gastric mucosa.

CONCLUSION

The in vivo measurement of gastric pH highlighted its key role in determining the minimal effective dose of oral T4 and may explain the interference of food, of some drugs and gut disorders on levothyroxine treatment.

Comparison Between Real-time Ammonium and pH Measurement, Immunohistochemistry, and Histochemistry for the Diagnosis of Helicobacter pylori

BACKGROUND

Helicobacter pylori (HP) infection has been implicated in several malignant and nonmalignant conditions. The confirmatory diagnosis of HP requires an endoscopic biopsy, followed by a rapid urease test, culture, and/or histopathologic examination using hemotoxylin and eosin, histochemical stains, or immunohistochemistry against HP. EndoFaster is a novel device that can perform real-time ammonium and pH measurements in gastric juice, allowing a diagnosis of HP during gastroduodenal endoscopy.

GOAL

This study aimed to validate the accuracy of EndoFaster and to compare different histochemical and immunohistochemical techniques for the diagnosis of HP infection.

STUDY

Consecutive patients who underwent upper endoscopy at our center were prospectively enrolled. During the endoscopy procedure, gastric juice was aspirated to perform an automatic analysis by EndoFaster and gastric biopsies were taken. Histologic sections were reviewed to assess the histopathologic features. The sensitivity, specificity, positive predictive value, and negative predictive value were calculated for the EndoFaster test, Diff-Quick (DQ), and immunohistochemistry against HP (anti-HP) using Warthin-Starry as the gold standard for HP detection.

RESULTS

Overall, 80 patients were enrolled. In 19 cases (23,75%), histology was normal. In the remaining cases, varying degrees of inflammation were found. The sensitivity, specificity, positive predictive value, and negative predictive value were 73.33%, 86.00%, 75.86%, and 84.31% for the EndoFaster test using 67 ppm/mL as the positive threshold; 73.33%, 100%, 100%, and 86.21% for DQ; and 79.31%, 88.00%, 79.31%, and 88.00% for anti-HP, respectively.

CONCLUSIONS

The EndoFaster test has good sensitivity and specificity for the diagnosis of HP during the gastroscopy procedure. DQ and anti-HP are excellent alternatives to Warthin-Starry for the detection of HP.

Daily requirement of softgel thyroxine is independent from gastric juice pH

BACKGROUND

Softgel levothyroxine (LT4) preparation showed a better in vitro dissolution profile at increasing pH as compared to tablet LT4 preparation. Clinical studies suggested a better performance of softgel LT4 preparation in patients with gastric disorders but whether this finding is related to gastric juice pH variation in vivo is not known.

METHODS

Twenty-eight hypothyroid patients (24F/4M; median age=50 treated with tablet LT4 (median dose= 1.65 µg/kg/day) and with stable thyroid stimulating hormone (TSH) values on target (<0.8-2.5> mU/l) have been shifted to softgel LT4 preparation. The dose of softgel LT4 has been titrated to obtain a similar individual serum TSH value. All subjects followed a specific treatment schedule, taking LT4 in fasting condition and then abstaining from eating or drinking for at least 1 hour. Owing to the presence of long-lasting dyspepsia or of already known gastric disorders, all patients underwent endoscopy, upon informed consent. Gastric juice has been collected during endoscopy to measure gastric pH. Then we plotted the dose of LT4 with the gastric pH obtained in vivo, before and after the switch tablet/softgel preparation in all patients.

RESULTS

Upon the switch tablet/softgel preparation, the therapeutic LT4 dose was very slightly reduced (-6%) in the whole sample. However, the individual variations revealed the existence of two populations, one without any dose reduction (A) and the other showing a dose reduction >20% (B). Upon matching with the actual gastric pH, patients with normal pH (A: n=17; 14F/3M, median 1.52) no showed a lower softgel LT4 requirement. Instead, among patients with reduced gastric acid production (B: n=11; 10F/1M, median pH 5.02) the vast majority (10/11; 91%, p<0.0001) benefited from a lower dose of softgel LT4 (median = -23%, p<0.0001). Interestingly, the dose of LT4 in tablet correlated with pH value (Spearman's ρ =0.6409; p = 0.0002) while softgel dose was independent from gastric juice pH (Spearman's ρ =1.952; p = 0.3194).

CONCLUSIONS

These findings provide evidence that softgel LT4 preparation is independent from the actual gastric pH in humans and may represent a significant therapeutic option in patients with increased LT4 requirement, owed to disorders impairing the gastric acidic output.

Hot and sour: parasite adaptations to honeybee body temperature and pH

Host temperature and gut chemistry can shape resistance to parasite infection. Heat and acidity can limit trypanosomatid infection in warm-blooded hosts and could shape infection resistance in insects as well. The colony-level endothermy and acidic guts of social bees provide unique opportunities to study how temperature and acidity shape insect-parasite associations. We compared temperature and pH tolerance between three trypanosomatid parasites from social bees and a related trypanosomatid from poikilothermic mosquitoes, which have alkaline guts. Relative to the mosquito parasites, all three bee parasites had higher heat tolerance that reflected body temperatures of hosts. Heat tolerance of the honeybee parasite Crithidia mellificae was exceptional for its genus, implicating honeybee endothermy as a plausible filter of parasite establishment. The lesser heat tolerance of the emerging Lotmaria passim suggests possible spillover from a less endothermic host. Whereas both honeybee parasites tolerated the acidic pH found in bee intestines, mosquito parasites tolerated the alkaline conditions found in mosquito midguts, suggesting that both gut pH and temperature could structure host-parasite specificity. Elucidating how host temperature and gut pH affect infection-and corresponding parasite adaptations to these factors-could help explain trypanosomatids' distribution among insects and invasion of mammals.

Helicobacter pylori Eradication Induced Constant Decrease in Interleukin- 1B Expression over More Than 5 Years in Patients with Gastric Cancer and Dysplasia

Background/Aims

Helicobacter pylori (Hp) suppresses gastric acid secretion by repressing the expression of the H⁺, K⁺-adenosine triphosphatase (H⁺, K⁺-ATPase) and stimulating interleukin-1 (IL-1β; encoded by IL-1B). This study was aimed at evaluating the expression of the H⁺, K⁺-ATPase and IL-1β after Hp eradication.

Methods

Two hundred twenty-one subjects were categorized as Hp-negative (n=84) or Hp-positive (n=137) according to the results of Hp tests (histology, CLO test, culturing, and serology). The mRNA expression levels of IL-1B and ATP4A (the gene encoding the α-subunit of H⁺, K⁺-ATPase) were measured in biopsy specimens from the gastric corpus using real-time polymerase chain reaction.

Results

The Hp-positive group had significantly higher IL-1B mRNA levels than the whole Hp-negative group and the intestinal metaplasia (IM)-negative subgroup. After Hp eradication, the difference between the Hp-negative and Hp-eradicated groups disappeared, including in the IM-negative subgroup. The IL-1B mRNA level did not significantly change from the baseline level. Within the gastric cancer (GC)/dysplasia subgroup, the IL-1B mRNA levels at 1, 2, 3–4, and ≥5 years after Hp eradication were significantly lower than the baseline level. The difference in ATP4A mRNA levels between the Hp-negative and Hp-positive groups was not significant at baseline, and the changes in the ATP4A mRNA levels after Hp eradication compared to the baseline levels in the whole group and subgroups stratified by the presence of IM and GC/dysplasia were not significant.

Conclusions

Infection with Hp has an effect on the level of IL-1B mRNA in IM-negative subjects. The continuous reduction in the IL-1B mRNA level in patients with GC/dysplasia after Hp eradication contributes to the prevention of metachronous GC after Hp eradication.

Role of gastrointestinal system on transmission and pathogenesis of SARS-CoV-2

Coronavirus disease 2019 (COVID-19) continues to pose a significant threat to global health. Primary prevention remains as a major strategy against the pandemic. Current evidence proves that aerosol and droplet-based routes are the main means of transmission of COVID-19 but other ways should be sought in order to prevent possible collateral transmission. The gastrointestinal system may be one such route. Angiotensin converting enzyme 2 is the target entry receptor for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that is abundantly expressed in the gastrointestinal tract. SARS-CoV-2 is able to infect human enterocytes similar to severe acute respiratory syndrome and Middle Eastern respiratory syndrome. Herein this review, we discuss the current knowledge regarding the role of gastrointestinal transmission in transmission and pathophysiology of COVID-19.

Jianpiyiqi formula ameliorates chronic atrophic gastritis in rats by modulating the Wnt/β-catenin signaling pathway

Jianpiyiqi formula is a Traditional Chinese Medicine (TCM) prescription and is used for the clinical treatment of patients with chronic atrophic gastritis (CAG). The aim of the present study was to examine the underlying mechanisms of Jianpiyiqi formula treatment for CAG via the Wnt/β-catenin signaling pathway. The high-performance liquid chromatography (HPLC) chromatogram of Jianpiyiqi formula was constructed. A CAG rat model induced by N-methyl-N'-nitro-N-nitrosoguanidine and ranitidine was established. The body weight and food intake of the rats was recorded and rat gastric morphology was visually examined. Pathological analysis of rat gastric tissue was also performed. The levels of gastrin (GAS), pepsin (PP), somatostatin (SS) and prostaglandin E₂ (PGE₂) in rat serum were detected using ELISAs. The expression levels of proteins and genes associated with the Wnt/β-catenin signaling pathway were measured via immunohistochemistry and reverse transcription-quantitative PCR. The HPLC chromatogram of Jianpiyiqi formula was determined and as active components, liquiritin and hesperidin were identified from the chromatogram. Compared with the blank group, the body weight and feed intake of the rats were decreased, and gastric mucosal atrophy and inflammation appeared in the model group. Treatment with Jianpiyiqi formula increased the body weight and feed intake of the rats, as well as relieved the gastric atrophy and inflammation. The contents of GAS, PP, SS and PGE₂ were significantly reduced in the model group compared with the blank group. Jianpiyiqi formula significantly increased GAS, PP, SS and PGE₂ levels in serum of rats with CAG. In the model group, Wnt1, β-catenin and cyclin D1 protein expression levels were increased, and glycogen synthase kinase-3β (GSK-3β) protein expression levels were decreased. Jianpiyiqi formula decreased the protein expression levels of Wnt1, β-catenin and cyclin D1 and increased the protein expression levels of GSK-3β. Compared with the blank group, the mRNA expression levels of Wnt1, Wnt5a, β-catenin, cyclin D1 and MMP7 were upregulated, and the mRNA expression levels of GSK-3β were downregulated in the model group. Treatment with Jianpiyiqi formula downregulated the mRNA expression levels of Wnt1, Wnt5a, β-catenin, cyclin D1 and MMP7 and upregulated the mRNA expression levels of GSK-3β. All of the experimental results indicated that Jianpiyiqi formula exerted a therapeutic effect on rats with CAG and inhibited the activation of the Wnt/β-catenin signaling pathway. Thus, Jianpiyiqi formula, as an effective TCM prescription for treating patients with CAG, may be more widely used in the clinic.

Histopathological classification and follow-up analysis of chronic atrophic gastritis

BACKGROUND

The pathological diagnosis and follow-up analysis of gastric mucosal biopsy have been paid much attention, and some scholars have proposed the pathological diagnosis of 12 kinds of lesions and accompanying pathological diagnosis, which is of great significance for the treatment of precision gastric diseases, the improvement of the early diagnosis rate of gastric cancer, and the reduction of missed diagnosis rate and misdiagnosis rate.

AIM

To perform a histopathological classification and follow-up analysis of chronic atrophic gastritis (CAG).

METHODS

A total of 2248 CAG tissue samples were collected, and data of their clinical characteristics were also gathered. Based on these samples, the expression levels of Mucin 1 (MUC1), MUC2, MUC5AC, and MUC6 in CAG tissue were tested by immunohistochemical assay. Moreover, we followed these patients for up to four years. The difference between different stages of gastroscopic biopsy was observed.

RESULTS

Through observation, it is believed that CAG should be divided into four types, simple type, hyperplasia type, intestinal metaplasia (IM) type, and intraepithelial neoplasia (IEN) type. Simple CAG accounted for 9.1% (205/2248), which was more common in elderly people over 60 years old. The main change was that the lamina propria glands were reduced in size and number. Hyperplastic CAG accounted for 29.1% (654/2248), mostly occurring between 40 and 60 years old. The main change was that the lamina propria glands were atrophy accompanied by glandular hyperplasia and slight expansion of the glands. IM CAG accounted for 50.4% (1132/2248), most of which increased with age, and were more common in those over 50 years. The atrophy of the lamina propria glands was accompanied by significant IM, and the mucus containing sialic acid or sulfate was distinguished according to the nature of the mucus. The IEN type CAG accounted for 11.4% (257/2248), which developed from the previous types, with severe gland atrophy and reduced mucus secretion, and is an important precancerous lesion.

CONCLUSION

The histological typing of CAG is convenient to understand the property of lesion, determine the follow-up time, and guide the clinical treatment.

Gastric Acid Powered Nanomotors Release Antibiotics for In Vivo Treatment of Helicobacter pylori Infection

Helicobacter pylori (H. pylori) infection has ≈75% probability of causing gastric cancer, so it is considered to be the strongest single risk factor for gastric malignancies. However, the harsh gastric acid environment has created obstacles to medical treatment. This work reports a nanomotor with a bottle-shaped container that can be loaded with small molecules of clarithromycin, nano calcium peroxide (CaO₂ ), and Pt nanoparticles (Pt NPs) by ultrasound. Nanomotors can quickly consume gastric acid through the chemical reaction of CaO₂ to temporarily neutralize gastric acid. The product hydrogen peroxide (H₂ O₂ ) is catalytically decomposed into a large amount of oxygen (O₂ ) by Pt NPs. The local concentration gradient of O₂ bubbles causes it to be expelled from the nanobottles through a narrow opening, and then push the nanobottles forward to provide maximum release and prodrug efficacy. Experiments in animal models show that 15 mg nanomotors can safely and quickly neutralize gastric acid in the stomach and simultaneously release prodrugs to achieve good therapeutic effects without causing acute toxicity. H. pylori burden in mice was 2.6 orders of magnitude lower than that in the control group. The stomach returns to normal pH within 1 d after administration.

Diagnostic Accuracy of EndoFaster® and Narrow-Band Imaging Endoscopy in Patients with Impaired Gastric Acid Secretion: A Real-Time Prospective Study

BACKGROUND

EndoFaster® analyzes gastric juice in real time during gastroscopy allowing the detection of hypo-achlorhydric conditions, like corpus atrophic gastritis. Narrow-band imaging (NBI) endoscopy allows to accurately detect and perform target biopsies in areas of intestinal metaplasia, a histological change often associated to corpus atrophic gastritis.

AIMS

To compare the diagnostic accuracy of EndoFaster® with histological evaluation for corpus atrophic gastritis through high-resolution (HR) NBI targeted biopsies.

METHODS

Prospective study on consecutive adult patients undergoing gastroscopy between April and November 2018. Patients in therapy with proton pump inhibitors, previous gastric surgery, and/or known gastric neoplasia were excluded. At the beginning of gastroscopy, gastric juice was aspirated and analyzed by EndoFaster® in 15 seconds. Endoscopists were blinded to the report of EndoFaster®. Evaluation of gastric mucosa in HR-white light was firstly performed, then with HR-NBI allowing to perform targeted biopsies on areas suspected for intestinal metaplasia; otherwise, biopsies were performed according to the updated Sydney System protocol and sent for histopathological evaluation.

RESULTS

Overall, 124 patients were included [64% F; 56 (18-85) years]. Corpus atrophic gastritis was present in 41.9% of patients. EndoFaster® showed an accuracy for corpus atrophic gastritis diagnosis, compared to histopathological evaluation as gold standard, of 87.1% and a sensitivity, specificity, PPV, and NPV of 78.8%, 93.1%, 89.1%, and 85.9%, respectively. pH showed a positive correlation with the severity score of atrophy (r = 0.67, 95% CI: 0.73-0.81, and p < 0.0001). EndoFaster® allowed to diagnose corpus atrophic gastritis in 3.7% of patients negative to NBI (corpus atrophic gastritis without intestinal metaplasia).

CONCLUSION

EndoFaster® seems a promising tool to diagnose corpus atrophic gastritis. The evaluation of hypo-achlorhydria during gastroscopy can address bioptic sampling in corpus atrophic gastritis patients without intestinal metaplasia.

The Impact of Gastric Juice pH on the Intraluminal Therapy for Helicobacter pylori Infection

Background: Helicobacter pylori (H. pylori) can be topically eradicated in stomach lumen on endoscopic examination. The procedures of intraluminal therapy for H. pylori infection (ILTHPI) include the control of intragastric pH, mucolytic irrigation of the gastric mucosal surface, and a single-dose medicament containing antimicrobial agents. Aims: To detect gastric juice pH and evaluate its impact on the success rate of ILTHPI. Methods: We enrolled 324 patients with upper abdominal discomfort for endoscopic examinations. Among them, 13C-urea breath test was positive in 218 patients, where 100 underwent ILTHPI, and negative in 106. All patients had their gastric juice pH detected and set into three ranges, including normal acidity (pH < 4.0), low-level hypoacidity (pH 4.0–5.5), and high-level hypoacidity (pH ≥ 6.0). The impact of gastric juice pH on the success rate of ILTHPI was evaluated. Results: Distribution of pH level showed no significant difference between two groups of H. pylori-infected patients (p = 0.942). The eradication rate of ILTHPI is significantly lower in patients with gastric juice pH below 4 (p < 0.001). Conclusions: Detection of gastric juice pH in ILTHPI is extremely important. Rapid control of stomach pH at or above 4 for patients prior to ILTHPI is strongly recommended. (NCT03124420).

Long non-coding RNAs towards precision medicine in gastric cancer: early diagnosis, treatment, and drug resistance

Gastric cancer is a deadly disease and remains the third leading cause of cancer-related death worldwide. The 5-year overall survival rate of patients with early-stage localized gastric cancer is more than 60%, whereas that of patients with distant metastasis is less than 5%. Surgical resection is the best option for early-stage gastric cancer, while chemotherapy is mainly used in the middle and advanced stages of this disease, despite the frequently reported treatment failure due to chemotherapy resistance. Therefore, there is an unmet medical need for identifying new biomarkers for the early diagnosis and proper management of patients, to achieve the best response to treatment. Long non-coding RNAs (lncRNAs) in body fluids have attracted widespread attention as biomarkers for early screening, diagnosis, treatment, prognosis, and responses to drugs due to the high specificity and sensitivity. In the present review, we focus on the clinical potential of lncRNAs as biomarkers in liquid biopsies in the diagnosis and prognosis of gastric cancer. We also comprehensively discuss the roles of lncRNAs and their molecular mechanisms in gastric cancer chemoresistance as well as their potential as therapeutic targets for gastric cancer precision medicine.

Endoscopic gastric mucosal atrophy as a predictor of colorectal polyps: a large scale case-control study

Although some studies have indicated a correlation between Helicobacter pylori infection and the risk of colorectal neoplasms, these findings have not been consistent and are controversial. This case-control study aimed to investigate the association between endoscopic gastric mucosal atrophy and colorectal polyp occurrence. Records of 7,394 participants who underwent colonoscopy examinations from August 2008 to July 2018 were reviewed retrospectively. A total of 2,404 subjects were registered; 1,565 (65.1%) were in the gastric mucosal atrophy-positive group and 1,138 (47.3%) had colorectal polyps. The multivariate analysis adjusted by age, sex, smoking habits, alcohol habits, hemoglobin A1c, and systolic blood pressure indicated that patients in the gastric mucosal atrophy-positive group more frequently had colorectal polyps compared with patients in the gastric mucosal atrophy-negative group (odds ratio, 3.27; 95% confidence interval, 2.68-4.01; p<0.001). An analysis of the association between gastric mucosal atrophy degree and colorectal polyp status indicated that, compared with mild gastric mucosal atrophy, severe gastric mucosal atrophy was associated with a higher risk of proximal colon polyps (odds ratio, 1.47; 95% confidence interval, 1.05-2.07; p = 0.024) and two or more colorectal polyps (odds ratio, 1.80; 95% confidence interval, 1.30-2.49; p<0.001). In conclusion, gastric mucosal atrophy found during esophagogastroduodenoscopy may be an indication for complete colon screening.

Proton pump inhibitors and dysbiosis: Current knowledge and aspects to be clarified

Proton pump inhibitors (PPIs) are common medications within the practice of gastroenterology. These drugs, which act through the irreversible inhibition of the hydrogen/potassium pump (H+/K+-ATPase pump) in the gastric parietal cells, are used in the treatment of several acid-related disorders. PPIs are generally well tolerated but, through the long-term reduction of gastric acid secretion, can increase the risk of an imbalance in gut microbiota composition (i.e., dysbiosis). The gut microbiota is a complex ecosystem in which microbes coexist and interact with the human host. Indeed, the resident gut bacteria are needed for multiple vital functions, such as nutrient and drug metabolism, the production of energy, defense against pathogens, the modulation of the immune system and support of the integrity of the gut mucosal barrier. The bacteria are collected in communities that vary in density and composition within each segment of the gastrointestinal (GI) tract. Therefore, every change in the gut ecosystem has been connected to an increased susceptibility or exacerbation of various GI disorders. The aim of this review is to summarize the recently available data on PPI-related microbiota alterations in each segment of the GI tract and to analyze the possible involvement of PPIs in the pathogenesis of several specific GI diseases.

Gastric Cancer Screening by Combined Determination of Serum Helicobacter pylori Antibody and Pepsinogen Concentrations: ABC Method for Gastric Cancer Screening

Objective:

Gastroscopy combined with gastric mucosa biopsies is currently regarded as a gold standard for diagnosis of gastric cancer. However, its application is restricted in clinical practice due to its invasive property. A new noninvasive population screening process combining the assay of anti-Helicobacter pylori antibody and serum pepsinogen (PG) (ABC method) is adopted to recognize the high-risk patients for further endoscopy examination, avoiding the unnecessary gastroscopy for most population and saving the cost consumption for mass screening annually. Nevertheless, controversies exist for the grouping of ABC method and the intervals of gastroscopy surveillance for each group. In this review, we summarized these popular concerned topics for providing useful references to the healthcare practitioner in clinical practice.

Data Sources:

The PubMed databases were systematically searched from the inception dates to November 22, 2017, using the keywords “Helicobacter pylori,” “Pepsinogens,” and “Stomach Neoplasms.”

Study Selection:

Original articles and reviews on the topics were selected.

Results:

Anti-H. pylori antibody and serum PG concentration showed significant changes under the different status of H. pylori infection and the progression of atrophic gastritis, which can be used for risk stratification of gastric cancer in clinic. In addition, anti-H. pylori antibody titer can be used for further risk stratification of gastric cancer contributing to determine better endoscopy surveillance interval.

Conclusions:

The early detection and diagnosis of gastric cancer benefit from the risk stratification, but the cutoff values for H. pylori antibody and serum PG concentration require further modification.