Autoimmune atrophic gastritis--pathogenesis, pathology and management

Double filtration plasmapheresis in autoimmune gastritis with subacute combined degeneration of the spinal cord: A case report

Autoimmune gastritis (AIG) is characterized by the destruction of gastric parietal cells, leading to vitamin B12 deficiency and potentially causing subacute combined degeneration of the spinal cord (SCD). We present a case of a 61-year-old male with AIG who developed SCD and underwent three sessions of double filtration plasmapheresis (DFPP), resulting in significant reduction of autoantibody titers and improvement in neurological symptoms. DFPP demonstrated efficacy in treating AIG complicated by SCD, offering potentially faster clinical response than conventional therapies by rapidly reducing autoantibody levels. This case underscores the importance of early diagnosis and intervention in preventing irreversible neurological damage, suggesting DFPP as a promising adjunctive treatment for AIG with SCD and warranting further investigation into its mechanisms and applications in autoimmune diseases.

Monitoring the follow-up of autoimmune chronic atrophic gastritis using parietal cell antibodies and markers of gastric function

Increased interest in the pathogenesis and the evolution of autoimmune chronic atrophic gastritis (A-CAG) has led to the search for serological markers that can be used to detect changes in the gastric mucosa at an early stage and to monitor the course of the disease. Parietal cell autoantibodies have been proposed as suitable immunological markers of atrophic damage, as they can be detected in the serum when symptoms of gastritis are not yet present. However, the utility of measuring only the level of parietal cell autoantibodies in the follow-up of A-CAG does not appear to suffice. Recent evidence has suggested that, in monitoring A-CAG, parietal cell antibodies should be associated with an evaluation of gastric function through biochemical and hormonal tests, such as pepsinogens and gastrin 17. This integrated approach will allow for the more effective real-time monitoring of the state of the gastric mucosa. As A-CAG is a progressive disorder associated with an increased risk of gastric cancer and neuroendocrine tumors, the precise follow-up of patients with gastric atrophy needs to be better defined. Further longitudinal studies in large cohorts must be performed with long-term follow-up.

Detection of the genetic association of circulating Helicobacter pylori antibodies with atrial fibrillation

Helicobacter pylori (H pylori) infection and H pylori antibodies have been reported to be associated with an increased risk of atrial fibrillation (AF) in several observational studies. However, whether this relationship is causal and which H pylori antibodies serve as the determinant of AF remains largely unclear. Recently published Genome-wide association studies on 7 different antibodies of H pylori-specific proteins and AF (2 correction methods) were included in this study. A two-sample Mendelian randomization study was employed to investigate the causal effects of circulating H pylori antibodies on the risk of AF. Genetically predicted serum H pylori Catalase antibody level was associated with an increased risk of AF (Firth correction) (odds ratio = 1.137, 95% confidence interval: 1.008-1.282, P = .037) and AF (saddlepoint approximation correction) (odds ratio = 1.139, 95% confidence interval: 1.010-1.284, P = .034). No significant causal correlations were found between other H pylori antibodies and AF. This Mendelian randomization study demonstrates that H pylori Catalase antibody is the only causal determinant associated with the risk of AF in terms of H pylori-related antibodies.

Associations Between Antiparietal Cell Antibody Values and Atrophy in a South and Southeast Asian General Population

GOALS

To investigate the association between atrophy severity and antiparietal cell antibody (APCA) levels in South and Southeast Asia.

BACKGROUND

APCA is an autoantibody that damages gastric parietal cells; autoimmune gastritis (AIG) is a chronic gastric inflammatory disease related to APCA and severe predominant corpus atrophy. Although a positive APCA result is a key clinical diagnostic tool for AIG, its rates vary widely among ethnic groups, and its exact relationship with AIG and predominant corpus atrophy remains unclear.

STUDY

Associations between histopathology-assessed and endoscopy-assessed atrophy, APCA positivity rates, Helicobacter pylori status, and pepsinogen levels were investigated in 1982 symptomatic patients from Vietnam, Thailand, Myanmar, Bangladesh, and Nepal.

RESULTS

Overall, 38.5% of participants were negative for Helicobacter pylori infection, while 57.6% had a current infection. A positive APCA result, defined as a titer >10, was present in 44.0% of participants (95% confidence interval: 41.8%-46.3%, 873/1982). Pathologic atrophy, corpus atrophy, and predominant corpus atrophy were found in 8.7% (169/1982), 5.1% (101/1982), and 4.1% (81/1982) of participants, respectively. Positive APCA rates significantly differed among countries (10.6% to 63.8%, P<0.001). No significant correlation was found between APCA results and the presence or severity of atrophy.

CONCLUSIONS

Although APCA positivity was high among symptomatic patients from South and Southeast Asian countries, few had severe predominant corpus atrophy or positive pepsinogen tests, which suggests a low rate of AIG in this population. Long-term surveillance of APCA-positive individuals is necessary to determine the clinical significance of a positive APCA result without AIG.

Autoimmune Metaplastic Atrophic Gastritis (AMAG): Regional Demographics and Their Effect on Prevalence

Autoimmune metaplastic atrophic gastritis (AMAG) is a chronic immune-mediated form of gastritis characterized by damage to oxyntic cells, ultimately resulting in both iron deficiency with or without anemia and pernicious anemia. The current dogma is that AMAG is a disease of White Northern European women of advanced age. We, therefore, sought to examine the prevalence of AMAG in biopsies obtained from populations enriched for self-identified Hispanics for cross-comparison against data from previously reported populations enriched for self-identified White, non-Hispanic patients. To that end, we prospectively collected 1708 sequential gastric biopsies performed at the University of Miami Hospitals/Jackson Health Systems clinics from 1692 patients over a 1-year period as well as pertinent clinical parameters. These Florida data were then compared against data previously collected from the Baltimore population, which has far lower numbers of Hispanic patients. Self-identified race and/or ethnicity were used. From these 1692 patients, we identified 79 patients (4.6%) with AMAG. These included 60 women (76%) and 19 men (24%), with a F:M ratio of 3.1:1. Patients had a median age of 60 years (range: 15-83). Self-identified race and/or ethnicity were: 60 (76.0%) Hispanic, 9 (11.4%) Black, 9 (11.4%) White, and 1 Asian (1.2%). The median age at initial presentation was: 51 years (range: 15-83) in Hispanics, 77.2 years (range: 46-74) in Blacks, 59 years (range: 49-79) in Whites, and 58 years in the only Asian patient. The overall demographics of AMAG largely mirrored the Florida population, with an over-representation of Hispanics (Florida inhabitants self-report as 70% Hispanic). The overall 4.6% prevalence of AMAG in the Florida population differed significantly from the 1.1% in Baltimore (p < .00001), a finding that presumably reflects the large Hispanic population. In fact, the prevalence of AMAG is far higher in Hispanic patients. Awareness of these data should increase recognition of AMAG in this population.

Risk Factors Analysis and Predictive Model Construction for Autoimmune Gastritis: A Nationwide Multicenter Case-Control Study in China

OBJECTIVE

Here, we ascertained the clinical characteristics of Chinese patients with autoimmune gastritis (AIG) and determined the correlation of dietary and lifestyle factors with AIG occurrence and development to establish a noninvasive predictive model for AIG.

METHODS

In this case-control study, we enrolled 479 patients from seven independent centers nationwide in China; of them, 279 had AIG, 112 had chronic atrophic gastritis mostly in the antrum, and 88 had chronic nonatrophic gastritis. Their clinical and lifestyle data were systematically collected and analyzed. Finally, a multivariate logistic regression disease prediction model was then established and validated.

RESULTS

Most of the 279 patients with AIG were middle-aged, older, and female. In the predictive model of AIG, the larger amount of cooking oil used per meal and comorbid autoimmune thyroid disease was considered risk factors, and a diet rich in vitamin B12 was considered a protective factor. We plotted a receiver operating characteristic (ROC) curve of the model in the discovery and validation cohorts, and the areas under the ROC curves were 0.72 and 0.74, respectively. In addition, dietary structure, eating habits, sleep quality, and smoking status were noted to be correlated with the occurrence of gastrointestinal symptoms and complications, as well as histopathological grades of AIG.

CONCLUSION

Dietary and lifestyle factors may predict AIG risk in Chinese populations and were related to AIG prognosis.

Clinical Heterogeneity of Early-Onset Autoimmune Gastritis: From the Evidence to a Pediatric Tailored Algorithm

Autoimmune gastritis (AIG) is an uncommon and often underestimated condition in children, characterized by chronic stomach inflammation leading to the destruction of oxyntic glands with subsequent atrophic and metaplastic changes. This condition is associated with hypo-/achlorhydria, impairing iron and vitamin B12 absorption. The pathogenesis involves the activation of helper type 1 CD4+/CD25-T-cells against parietal cells. Clinical manifestations in children are not specific and include abdominal pain, bloating, nausea, vomiting, and iron deficiency anemia (IDA). The disease is also linked to an increased risk of pernicious anemia, intestinal-type gastric cancer, and type I neuroendocrine tumors. AIG is often diagnosed through the presence of autoantibodies in the serum, such as parietal cell (APCA) and intrinsic factor (IF) antibodies. However, therapeutic recommendations for pediatric AIG are currently lacking. We aim to present two clinical cases of pediatric-onset AIG, highlighting the heterogeneous clinical manifestations and the challenges in diagnosis with the support of an updated literature review. A 9-year-old girl presented with refractory IDA, initial hypogammaglobulinemia, and a 12-year-old boy was initially diagnosed with eosinophilic esophagitis. Both cases underline the importance of considering AIG in children with chronic gastrointestinal symptoms and gastric atrophy. Diagnostic workup, including endoscopy and serological tests, is crucial for accurate identification. A better understanding of this condition is imperative for timely intervention and regular monitoring, given the potential long-term complications, including the risk of malignancy. These cases contribute to expanding the clinical spectrum of pediatric AIG and highlight the necessity for comprehensive evaluation and management in affected children.

Gastric cancer in patients with Helicobacter pylori-negative autoimmune gastritis

Although Helicobacter pylori (H. pylori) is implicated in the development of most cases of gastric cancer with autoimmune gastritis, cases of gastric cancer have been reported in patients testing negative for H. pylori. Here, we aimed to outline the current research status of the factors involved in the development of gastric cancer in H. pylori-negative autoimmune gastritis. Predictive pathological conditions for the development of gastric cancer in H. pylori-negative autoimmune gastritis are postulated to be: (1) Severe atrophy; (2) Hypergastrinemia; (3) Bile reflux; and (4) Low acidity, which are directly related to the pathophysiology of autoimmune gastritis, as well as smoking and family history, which are not related to autoimmune gastritis. In autoimmune gastritis, where there is a possibility of spontaneous disappearance of H. pylori in advanced atrophy, it is difficult to assess H. pylori. Since H. pylori infection begins in the antrum and subsequently progresses to the proximal stomach, it is interpreted as H. pylori-negative autoimmune gastritis if histologically consistent with autoimmune gastritis in the body with spared antrum, and negative for other H. pylori tests. However, it is essential to examine whether the currently prevailing histological interpretation used to evaluate H. pylori infection status is appropriate.

A real-world study on the characteristics of autoimmune gastritis: A single-center retrospective cohort in China

BACKGROUND AND AIM

Autoimmune gastritis (AIG) was previously considered a rare disease in China, and its clinical characteristics were not fully understood. This study aimed to demonstrate the characteristics of AIG in China and evaluate gastric oxyntic mucosal atrophy using a modified AIG-atrophic staging.

METHODS

This was a single-center retrospective observational real-world study. The diagnosis of AIG was based on pathological results combined with parietal cell antibody (PCA) and intrinsic factor antibody (IFA) results, and endoscopic findings.

RESULTS

A total of 745 patients were enrolled, the median age at diagnosis was 58 years old, and 69.9 % were female. The symptoms of AIG patients were nonspecific, and about 2/5 of the cases were asymptomatic. The proportions of cases from modified AIG-atrophic stage 1 to 4 were 0.8 %, 14.1 %, 73.8 %, and 11.3 %, respectively. Approximately 1/5 had autoimmune thyroiditis (AITD). Near 1/2 had one or more comorbidities: iron-deficiency anemia (IDA), pernicious anemia (PA), neuropathy, gastric hyperplastic polyps (GHP), gastric intraepithelial neoplasia (GIN), type 1 gastric neuroendocrine tumors (g-NET), or gastric adenocarcinoma (GAC). There was a high risk of type 1 g-NET (7.0 %) and GAC (9.1 %) in AIG patients.

CONCLUSIONS

AIG is not rare in China, and its early diagnosis is challenging, accompanied by a high risk of GAC. The modified four-stage AIG-atrophic staging can effectively represent the extent of oxyntic mucosal atrophy and the progression in AIG.

A novel endoscopic artificial intelligence system to assist in the diagnosis of autoimmune gastritis: a multicenter study

BACKGROUND

 Autoimmune gastritis (AIG), distinct from Helicobacter pylori-associated atrophic gastritis (HpAG), is underdiagnosed due to limited awareness. This multicenter study aimed to develop a novel endoscopic artificial intelligence (AI) system for assisting in AIG diagnosis.

METHODS

 Patients diagnosed with AIG, HpAG, or nonatrophic gastritis (NAG), were retrospectively enrolled from six centers. Endoscopic images with relevant demographic and medical data were collected for development of the AI-assisted system based on a multi-site feature fusion model. The diagnostic performance of the AI model was evaluated in internal and external datasets. Endoscopists' performance with and without AI support was tested and compared using Mann-Whitney U test. Heatmap analysis was performed to interpret AI model outputs.

RESULTS

 18 828 endoscopy images from 1070 patients (294 AIG, 386 HpAG, 390 NAG) were collected. On testing datasets, AI identified AIG with 96.9 % sensitivity, 92.2 % specificity, and area under the receiver operating characteristic curve (AUROC) of 0.990 (internal), and 90.3 % sensitivity, 93.1 % specificity, and AUROC of 0.973 (external). The performance of AI (sensitivity 91.3 %) was comparable to that of experts (87.3 %) and significantly outperformed nonexperts (70.0 %; P = 0.01). With AI support, the overall performance of endoscopists was improved (sensitivity 90.3 % [95 %CI 86.0 %-93.2 %] vs. 78.7 % [95 %CI 73.6 %-83.2 %]; P = 0.008). Heatmap analysis revealed consistent focus of AI on atrophic areas.

CONCLUSIONS

 This novel AI system demonstrated expert-level performance in identifying AIG and enhanced the diagnostic ability of endoscopists. Its application could be useful in guiding biopsy sampling and improving early detection of AIG.

Autoimmune Gastritis in Korean Patients with Gastric Tumors: Clinicopathologic Correlations and Diagnostic Histological Features

Background/Aims

Autoimmune gastritis (AIG) is a corpus-dominant atrophic gastritis in which patients are positive for antiparietal cell antibody (APCA) and/or anti-intrinsic factor antibody. The risk of developing gastric cancer in patients with AIG remains unclear, and reliable frequency data of AIG in patients with gastric cancer are lacking.

Methods

We included 624 Korean patients with gastric tumors (612 gastric cancers and 12 neuroendocrine tumors) who had APCA results and were available for AIG evaluation. In patients with positive APCA results, endoscopy and histology findings were reviewed to diagnose AIG.

Results

Of the 624 patients, 37 (5.9%) tested positive for APCA, and ultimately, 11 (1.8%) met the diagnostic criteria for AIG (5 both endoscopy and histology findings, 4 endoscopy-only findings, 2 histology-only findings). The frequency of AIG in patients with gastric cancer was 1.3% (8/612), and that in patients with neuroendocrine tumors was 25.0% (3/12). Of the 11 patients with AIG, serum Helicobacter pylori antibody was positive in six patients (54.5%), all of whom had gastric cancer. Histologically, three patients showed pure AIG, four patients exhibited concurrent AIG and H. pylori gastritis, and the findings for four were indefinite for AIG. The pepsinogen (PG) I levels and PG I/II ratio were significantly lower in patients with gastric cancer with AIG than in patients with gastric cancer without AIG (p=0.042 and p=0.016, respectively).

Conclusions

The frequency of AIG in gastric cancer patients was very low compared to that in patients with neuroendocrine tumors. Rather, concurrent AIG and H. pylori gastritis was common in patients with AIG with gastric cancer.

Common occurrence of atrophic gastritis in an ageing non-hospitalised population: an autopsy study

BACKGROUND

Atrophic gastritis-the end stage of chronic gastritis-is an asymptomatic disease due to Helicobacter pylori infection causing decreased vitamin B12 and folate absorption, which may lead to severe haematological and neuropsychological disorders including Alzheimer's disease. The diagnosis requires endoscopy and biopsies from symptomatic patients, explaining why its true prevalence in the population is not well-known.

OBJECTIVE

We aimed to evaluate the prevalence of various stages of chronic gastritis in an autopsy series most closely representing the general population.

SUBJECTS AND METHODS

Gastric mucosa samples were collected prospectively from out-of-hospital deaths included in the Tampere Sudden Death Study (n = 70, mean age 63, age range 22-91 years). Antrum and corpus samples were stained with a H. pylori antibody and staged histopathologically.

RESULTS

Chronic gastritis with or without atrophic changes was detected in 40% of the cases. The proportion of healthy mucosa decreased age-dependently from 71.4% among individuals aged <50 years to 43.5% among the oldest individuals (>70 years), and that of chronic non-atrophic gastritis from 21.4% to 8.7%. In contrast, the prevalence of atrophic gastritis was 27.1% and increased in the age groups from 7.1% to 47.8% (P = .019) among the oldest individuals, showing a strong association (P < .0001) with H. pylori immunopositivity.

CONCLUSIONS

Atrophic gastritis is a common feature of the ageing stomach, which is observed in every second individual aged 70+ years, showing a strong association with H. pylori immunopositivity. Atrophic gastritis may be a more common risk factor in old age for diseases associated with low serum B12 and folate levels than has been previously known.

Real-Time Gastric Juice Analysis to Rule Out the Presence of Autoimmune Gastritis: A Case-Control Study

BACKGROUND

Autoimmune gastritis (AIG) is an infrequent disease predisposing to both neuroendocrine tumours and cancer. This study aimed to evaluate whether pH measurement of gastric juice allows accurate exclusion of the presence of AIG in real time so that gastric mucosa sampling on normal-appearing mucosa may be avoided.

METHODS

This study enrolled patients diagnosed with AIG and matched controls (ratio 1:5) who underwent upper endoscopy with standard gastric mucosa sampling and real-time, gastric juice pH assessment. A threshold of pH less than 4.5 was adopted as cut-off to rule out the presence of a feature of AIG. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), overall accuracy, positive likelihood ratio (LR+), and negative likelihood ratio (LR-) were calculated.

RESULTS

Data of 40 patients (M/F: 19/21; mean age: 58 years, range: 18-89) with AIG and 212 matched controls were evaluated. Among AIG patients, the feature of atrophy/metaplasia of the oxyntic mucosa was staged as mild in 9 cases, moderate in 9, and severe in the remaining 22 patients. Gastric juice analysis showed a pH value >4.5 in 29 (72.5%) patients and 12 (5.7%) controls. Sensitivity, specificity, accuracy, PPV, NPV, LR+, and LR- were 73% (95% CI = 0.57-0.84), 94% (95% CI = 0.90-0.97), 71% (95% CI = 0.64-0.74), 95% (95% CI = 0.93-0.97), 91% (95% CI = 0.87-0.95), 12.9 (95% CI = 7.19-23.03), and 0.29 (95% CI = 0.18-0.48), respectively. The histological assessment of false-negative cases showed the presence of only mild-moderate atrophy of oxyntic mucosa in 6 (54.5%) cases, and severe in the others.

CONCLUSIONS

Our data found that real-time pH evaluation of gastric juice allows ruling out AIG with a very high NPV, but further studies are needed.

Vitexin alleviates MNNG-induced chronic atrophic gastritis via inhibiting NLRP3 inflammasome

ETHNOPHARMACOLOGICAL RELEVANCE

The dried fruit of Crataegus pinnatifida Bunge (Hawthorn in Chinese) is a traditional medicine used in China, Japan and Korea for thousands of years. Hawthorn is documented in the Chinese Pharmacopoeia, as a folk medicine that is used to eliminate food, strengthen the stomach, move qi and dissipate blood stasis, treat stagnation of meat and food, gastric distention and fullness, and has anti-inflammatory effects. Vitexin, a flavonoid glycoside, is an important biologically active compound derived from Hawthorn, with significant antioxidant and anti-inflammatory properties. The pharmacological effects of Hawthorn are highly correlated with the antioxidant and anti-inflammatory effects of vitexin.

AIM OF THE STUDY

The aim of the present study was to investigate the effect of vitexin on the alleviation of chronic atrophic gastritis (CAG) induced by 1-methyl-3-nitro-1-nitrosoguanidine (MNNG) in a rat model, as well as to elucidate the underlying mechanisms involved.

MATERIALS AND METHODS

CAG was administered at a concentration of 170 μg/mL MNNG in the drinking water of rats, and the effects of vitexin (30 mg/kg, once daily for 6 weeks) on gastric tissues were subsequently analyzed. Pathological damage was assessed using H&E and AB-PAS staining. Gastrointestinal hormone levels, specifically motilin (MTL) and gastrin (GAS), were quantified using biochemical index determination kits. To evaluate the levels of cytokines, specifically IL-1β and IL-18, in gastric tissue, an enzyme-linked immunosorbent assay (ELISA) was performed. Additionally, to investigate the effects of vitexin on the NLRP3 inflammasome, GES-1 cells were subjected to treatment with lipopolysaccharide (LPS) and adenosine triphosphate (ATP). The targeting of NLRP3 by vitexin was assessed in vitro using CESTA, DARTS, and a synthesized biotin-labeled vitexin probe (biotin-vitexin) in conjunction with dual immunofluorescence. RT-PCR, Western blotting and immunofluorescence were used to evaluate the ameliorative effect of oysterin on LPS + ATP-induced GES-1 cells in vitro.

RESULTS

Administration of vitexin significantly alleviated the symptoms of chronic atrophic gastritis (CAG) by reducing weight loss and minimizing gastric tissue damage. Treatment with vitexin in CAG rats effectively reduces the production of pro-inflammatory cytokines. Furthermore, vitexin attenuated the activation of the NLRP3 inflammasome in CAG induced by MNNG. Mechanistic experiments showed that NLRP3 is a direct cellular target of vitexin, while vitexin inhibited rat NLRP3 inflammasome.

CONCLUSION

Vitexin mitigates MNNG-induced CAG, and its protective effect is linked to the inhibition of NLRP3 inflammasome activation.

Traditional Chinese Medicine in the treatment of chronic atrophic gastritis, precancerous lesions and gastric cancer

ETHNOPHARMACOLOGICAL RELEVANCE

Chronic atrophic gastritis (CAG), precancerous lesions of gastric cancer (PLGC), and gastric cancer (GC), seriously threaten human health. Traditional Chinese medicine (TCM) has been employed in the treatment of chronic diseases for a long time and has shown remarkable efficacy.

AIM OF THE STUDY

Recently, there has been an increasing use of TCM in treating CAG, PLGC, and GC. The objective of this study is to compile a comprehensive overview of the existing research on the effects and molecular mechanisms of TCM, including formulas, single herbs, and active components.

MATERIALS AND METHODS

To obtain a comprehensive understanding of traditional use of TCM in treating these diseases, we reviewed ancient books and Chinese literature. In addition, keywords such as "TCM", "CAG", "PLGC", "GC", and "active ingredients" were used to collect modern research on TCM published in databases such as CNKI, Web of Science, and Pubmed up to April 2024. All collected information was then summarized and analyzed.

RESULTS

This study analyzed 174 articles, which covered the research progress of 20 TCM formulas, 14 single herbs, and 50 active ingredients in treating CAG, PLGC, and GC. Sources, effects, and molecular mechanisms of the TCM were summarized.

CONCLUSIONS

This article reviews the progress of TCM in the management of CAG, PLGC, and GC, which will provide a foundation for the clinical application and further development of TCM.

Association between autoimmune gastritis and gastric polyps: Clinical characteristics and risk factors

BACKGROUND

The relationship between autoimmune gastritis (AIG) and gastric polyps (GPs) is not well understood.

AIM

To explore the clinical characteristics and risk factors of AIG with GPs in patients.

METHODS

This double center retrospective study included 530 patients diagnosed with AIG from July 2019 to July 2023. We collected clinical, biochemical, serological, and demographic data were of each patient. Logistic regression analyses, both multivariate and univariate, were conducted to pinpoint independent risk factors for GPs in patients with AIG patients. Receiver operating characteristic curves were utilized to establish the optimal cutoff values, sensitivity, and specificity of these risk factors for predicting GPs in patients with AIG.

RESULTS

Patients with GPs had a higher median age than those without GPs [61 (52.25-69) years vs 58 (47-66) years, P = 0.006]. The gastrin-17 levels were significantly elevated in patients with GPs compared with those without GPs [91.9 (34.2-138.9) pmol/mL vs 60.9 (12.6-98.4) pmol/mL, P < 0.001]. Additionally, the positive rate of parietal cell antibody (PCA) antibody was higher in these patients than in those without GPs (88.6% vs 73.6%, P < 0.001). Multivariate and univariate analyses revealed that PCA positivity [odds ratio (OR) = 2.003, P = 0.017], pepsinogen II (OR = 1.053, P = 0.015), and enterochromaffin like cells hyperplasia (OR = 3.116, P < 0.001) were significant risk factors for GPs, while pepsinogen I was identified as a protective factor.

CONCLUSION

PCA positivity and enterochromaffin like cells hyperplasia are significant risk factor for the development of GPs in patients with AIG. Elevated gastrin-17 levels may also play a role in this process. These findings suggest potential targets for further research and therapeutic intervention in managing GPs in patients with AIG.

Endoscopic and clinical characteristics of autoimmune atrophic gastritis: Retrospective study

Background and study aims

Autoimmune atrophic gastritis (AIG) is a rare chronic autoimmune disease characterized by gastric mucosa inflammation and atrophy. Limited clinical data exist about AIG, especially in western populations. In addition, there are no western series on the magnifying endoscopic features in AIG. This study presents a cohort of 63 patients with AIG, reporting their clinical, laboratory, and endoscopic findings.

Patients and methods

A retrospective analysis was conducted on patients diagnosed with AIG at Kingston Health Sciences Centre, Canada, between January 2016 and December 2023. Data collected from medical records included age, sex, presenting symptoms, laboratory findings, endoscopic features, histopathology reports, and concomitant autoimmune diseases.

Results

The study included 63 patients with autoimmune gastritis. Positive anti-parietal cell antibodies were found in the majority of patients (84.13%), whereas positive anti-intrinsic factor antibodies were less prevalent (25.40%). Deficiencies in vitamin B12 (49.21%) and iron (76.19%) were observed, along with a high prevalence of anemia (71.43%) and concomitant autoimmune diseases (58.73%). The dominant magnification pattern of atrophy in the body was oval/slit in 57.14% of patients (n=36), followed by tubular in 30.16% (n=19) and foveolar in 12.70% (n=8). Prevalence of neoplasia in our study was 42.86% (n=27).

Conclusion

This study offers insights into the clinical, laboratory, and magnifying endoscopic features of patients with AIG. It demonstrates the three main magnifying endoscopic appearances of AIG and highlights the significant prevalence of gastric neoplasia, even in the low-risk Western population. These findings emphasize the importance of the endoscopic exam in identifying AIG and notably present the key magnifying endoscopy findings in a Western setting for the first time.

Antral mucosa healing at long-term follow-up in patients with corpus atrophic gastritis and concomitant antral gastritis may mimic autoimmune gastritis

BACKGROUND AND AIM

Corpus atrophic gastritis (CAG) is defined as autoimmune when the antrum is spared, representing this element a crucial diagnostic criterium of autoimmune gastritis. In contrast, CAG with concomitant antral gastritis (AG), atrophic or non-atrophic, is generally attributed to H. pylori infection. During the natural history of CAG, possible antrum healing has been supposed. The current study aimed to assess the antral mucosa histopathological changes at long-term follow-up (FU) with respect to baseline in patients with CAG and concomitant atrophic or non-atrophic gastritis AG.

METHODS

Retrospective study on 130 patients with histologically diagnosed CAG with atrophic or non-atrophic AG. Mean FU gastroscopy was at 40.6 (range 4-192) months. Patients with confirmed CAG (n = 117; median age 66, range 20-87 years; 67.5 % F) were finally included. At baseline, 47 (40.2 %) had non-atrophic and 70 (59.8 %) atrophic AG. Helicobacter pylori (Hp) infection was present at histology in 27.3 % of patients, all treated.

RESULTS

At FU, 30/117(25.6 %) patients showed a complete antral healing; 11/29(37.9 %) were Hp positive at baseline, cured in all but one. Atrophic AG regressed in 16/70(22.8 %) patients. Both, antral healing and regression of antral AG, were found to be similar in Hp-cured and not-cured/ naïve-negatives patients (p > 0.05).

CONCLUSION

In a subset of CAG patients, AG may regress at long-term FU irrespective of Hp cure, thus mimicking autoimmune atrophic gastritis and raising concerns about its current histopathological diagnostic criteria.

Distinguishing Features of Autoimmune Gastritis Depending on Previous Helicobacter pylori Infection or Positivity to Anti-Parietal Cell Antibodies: Results From the Autoimmune gastRitis Italian netwOrk Study grOup (ARIOSO)

INTRODUCTION

To describe the clinical features and the risk of developing gastric tumors in patients with autoimmune gastritis (AIG).

METHODS

This was a retrospective, longitudinal, multicenter study conducted at 8 Italian tertiary referral centers. We retrieved clinical data from all histologically proven patients with AIG. Differences between Helicobacter pylori -exposed vs H. pylori -naive and anti-parietal cell antibody (PCA)-positive vs PCA-negative patients were investigated. The rate of gastric adenocarcinoma and type 1 gastric neuroendocrine neoplasm (gNEN) was assessed. A multivariable model for factors associated with gNEN was fitted.

RESULTS

A total of 1,598 patients with AIG (median age 58 years, interquartile range 46-68; F:M ratio 2.7:1) were included. H. pylori -naive patients were more likely to have a first-degree family history of AIG (14.7% vs 8.9%; P = 0.012), type 1 diabetes mellitus (4.9% vs 2.3%; P = 0.025), and pernicious anemia (30.9% vs 21.1%; P = 0.003). PCA-positive patients had significantly more associated autoimmune diseases (59.0% vs 42.9%; P < 0.001) and were more likely to have been diagnosed by a case-finding strategy (15.3% vs 2.6%; P < 0.001). Overall, 15 cases (0.9%) of gastric adenocarcinoma and 153 cases (9.6%) of gNEN occurred, with a global rate of 0.12 (95% confidence interval [CI] 0.07-0.20) and 1.22 (95% CI 1.03-1.42) per 100 person/year, respectively. Having a vitamin B12/iron deficiency manifestation at AIG diagnosis was associated with a 16.44 (95% CI 9.94-27.20 P < 0.001) hazard ratio of gNEN.

DISCUSSION

The "pure" AIG pattern has typical features of an autoimmune disease and seems to be unrelated to H. pylori . In a tertiary referral setting, the risk of developing overt gastric adenocarcinoma is low, while patients with vitamin B12 deficiency complications at onset may benefit from a more intense endoscopic follow-up for early gNEN detection.

Host-related low-prevalence gastritides: Epidemiological and clinical characterization

INTRODUCTION

A recent consensus meeting (RE.GA.IN) addressed "host-related, low-prevalence gastritis": eosinophilic (EoG), lymphocytic (Hp-pos_LyG and Hp-neg_LyG), collagenous (CollG), and granulomatous gastritis (GrG). Our study evaluates their clinico-epidemiological characteristics.

MATERIALS AND METHODS

We extracted all patients with a diagnosis of EoG, LyG, CollG, and GrG from a clinicopathological database and compared their demographics, clinical and endoscopic characteristics, associated conditions, and clinical awareness to those of all other subjects in the database (controls).

RESULTS

There were 1,781,005 unique patients (median age 57 years; 55.7 % female). Hispanics were overrepresented amongst those with Hp-pos_LyG. Subjects with GrG had a high prevalence of erosions and ulcers. Clinical awareness of these conditions was dismal (<1:10,000 patients). Some clinical manifestations were more common in patients with certain gastritides (e.g., vomiting and diarrhea in CollG; anemia in LyG), but none were sufficiently distinctive to suggest a clinical diagnosis. EoG was associated with EoE; LyG had a strong association with celiac disease; CollG with microscopic colitis; and GrG with Crohn disease.

CONCLUSIONS

The diagnosis of these gastritides (between <1: in 1,000 and 1 in 5000 subjects) rests on histopathology. They remain poorly characterized and clinically neglected. Yet, their associations may herald other conditions: eosinophilic gastrointestinal diseases (EGID), celiac, and Crohn disease. Patients might benefit from increased detection and characterization.

Helicobacter pylori and autoimmunity in atrophic gastritis - comparison of clinical, endoscopic and histopathological features

Objective

This study aims to investigate the clinical, endoscopic, biologic and histopathological differences between Helicobacter pylori-associated and autoimmune gastric atrophy.

Methods

A retrospective analysis was conducted on 95 patients diagnosed with either H. pylori-related corporal and antral atrophy (43 patients) or autoimmune corporal atrophic gastritis (52 patients).

Results

A significant male predisposition for H. pylori-associated atrophic changes in both the antrum and corpus regions (p=0.007, OR=3.24) was observed in comparison with autoimmune etiology of atrophy. While comorbidities and lifestyle factors showed similar distributions across groups, only unintentional self-reported weight loss demonstrated a significant association with H. pylori atrophy (p=0.0177, OR=3.94). Corporal erosions were strongly associated with antral and corporeal atrophic gastritis (p=0.04, OR=8.27), but the rest of mucosal lesions are comparable among groups. Interestingly, patients with H. pylori-related pangastric atrophy exhibited lower frequencies of altered triglyceride (p=0.018) and cholesterol (p=0.029) levels compared to the autoimmune group. Linear regression analysis identified low triglyceride levels as an independent predictor for H. pylori-associated antral and corporal atrophic gastritis (p=0.04) in endoscopic population with atrophy, but no hematological or clinical parameters were predictive for these changes.

Conclusions

Male patients are more likely to present with corpus atrophic gastritis associated with H. pylori infection than with an autoimmune etiology. Patients with atrophic gastritis tend to have similar clinical characteristics, except for dyslipidemia, which is more prevalent in those with H. pylori pangastritis. Corporal erosions are associated with active H. pylori infection in atrophic mucosa.

Clinical characteristics and outcomes of pediatric patients with autoimmune gastritis

OBJECTIVES

Autoimmune gastritis (AIG) is a rare chronic inflammatory disorder with potential long-term sequelae including gastric neoplasia. There is limited data on the natural history of pediatric AIG. We aimed to characterize the clinical course and outcomes of children with AIG.

METHODS

This was a multicenter retrospective study that included pediatric patients diagnosed with AIG between January 1, 2000 and December 31, 2021. Diagnosis of AIG was based on the demonstration of histological corpus-predominant atrophic gastritis, with or without positive antiparietal cell (APCA) or anti-intrinsic factor (IF) antibodies. Demographic, clinical, laboratory, endoscopic, and histologic data were retrieved, along with follow-up data.

RESULTS

Thirty-three patients, (23 females [69.7%], median age 12.0 [interquartile range 7.0-15.0] years at diagnosis) were identified. Twenty-two patients (66.7%) had positive APCA and/or anti-IF serology. The most common presenting manifestation was iron deficiency anemia (75%), and accompanying autoimmune disorders were significantly more common in patients with positive serology (62% vs. 18%, p < 0.05). Pseudo-pyloric or intestinal-type metaplasia was present at diagnosis in eight patients (24%), and 11 additional patients (33%) developed metaplasia during a median follow-up time of 27 (17.5-48.3) months. One patient developed a type 1 gastric neuroendocrine tumor. Helicobacter pylori was identified in only one patient, while two patients had prior eradication. Endoscopic and histologic improvements weren't identified in any patients.

CONCLUSIONS

AIG should be considered in patients with autoimmunity and resistant iron-deficiency anemia. H. pylori infection may not be associated with pediatric AIG. The development of neuroendocrine tumor in one patient, and the high rates of metaplasia, highlight the importance of surveillance.

A Rare Case of Gastric Neuroendocrine Tumor in a Patient With Vitamin B12 Deficiency

Vitamin B12 deficiency can result from gastric neuroendocrine tumors (GNETs), which are uncommon neoplasms frequently linked to hypergastrinemia and chronic atrophic gastritis. Here, we report the case of a 48-year-old vegetarian male from South India who presented with jaundice, fatigue, and gastrointestinal discomfort. He was diagnosed with macrocytic anemia, mild hepatomegaly, and significant vitamin B12 deficiency. An incidental upper gastrointestinal endoscopy revealed multiple gastric nodules, later confirmed as a well-differentiated GNET. The patient also had a high hepatitis B viral load. He was treated with vitamin B12 supplementation and underwent resection of the tumor followed by antiviral therapy for hepatitis B. Postoperative recovery was uneventful with improvements in anemia and liver function. This case emphasizes the importance of a multidisciplinary approach and thorough evaluation when addressing patients with vitamin B12 insufficiency, hepatitis B, and GNET.

Improving the Diagnosis of Autoimmune Gastritis: From Parietal Cell Antibodies to H+/K+ ATPase Antibodies

Parietal cell autoantibodies (PCAs), which recognize the enzyme H+/K+-ATPase as a target, are considered to be a diagnostic marker of autoimmune gastritis and pernicious anemia; these conditions are characterized by the presence of corpus atrophic gastritis. Circulating PCAs can be detected using several analytical methods that are commonly available in the clinical laboratory. Traditionally, indirect immunofluorescence (IIF) on rodent or primate stomach tissue is used as a screening test for the detection of PCAs. However, IIF suffers from a high inter-observer variability and lacks standardization. In addition, like immunoblotting, results are expressed only in a qualitative or semi-quantitative manner. Based on the few available studies that are reviewed herein, quantitative enzyme-linked immunosorbent assays (ELISAs) and fluorescence enzyme immunoassays (FEIAs) using purified H+/K+-ATPase perform better than IIF in the detection of PCAs, displaying higher sensitivity and utility in monitoring the disease. In light of their higher diagnostic accuracy, these solid-phase methods should be preferred to IIF in the screening of autoimmune atrophic gastritis. The use of methods to detect antibodies versus a specific subunit of H+/K+-ATPase (α or β) is currently confined to the world of research. Further investigation is required to define the clinical utility of H+/K+-ATPase subunit detection.

The Role of Viruses in the Pathogenesis of Immune-Mediated Gastro-Intestinal Diseases

Immune-mediated gastrointestinal (GI) diseases, including achalasia, celiac disease, and inflammatory bowel diseases, pose significant challenges in diagnosis and management due to their complex etiology and diverse clinical manifestations. While genetic predispositions and environmental factors have been extensively studied in the context of these conditions, the role of viral infections and virome dysbiosis remains a subject of growing interest. This review aims to elucidate the involvement of viral infections in the pathogenesis of immune-mediated GI diseases, focusing on achalasia and celiac disease, as well as the virome dysbiosis in IBD. Recent evidence suggests that viral pathogens, ranging from common respiratory viruses to enteroviruses and herpesviruses, may trigger or exacerbate achalasia and celiac disease by disrupting immune homeostasis in the GI tract. Furthermore, alterations in the microbiota and, specifically, in the virome composition and viral-host interactions have been implicated in perpetuating chronic intestinal inflammation in IBD. By synthesizing current knowledge on viral contributions to immune-mediated GI diseases, this review aims to provide insights into the complex interplay between viral infections, host genetics, and virome dysbiosis, shedding light on novel therapeutic strategies aimed at mitigating the burden of these debilitating conditions on patients' health and quality of life.

Chronic Atrophic Autoimmune Gastritis: The Evolving Role of Vitamin D

Vitamin D possesses a crucial role in preserving bone health, modulating the immune system responses, and supporting various physiological functions throughout the body. Chronic atrophic autoimmune gastritis (CAAG) constitutes an autoimmune condition marked by inflammation and damage to the stomach cells, often resulting in a decreased ability to absorb certain nutrients, including vitamin B12 and iron. Although, vitamin D is not directly affected by this condition, the sufficiency of this micronutrient seems to have important implications for overall health and management of the disease. The aim of the current review was to assess the incidence and related features of vitamin D deficiency in patients with CAAG and to elucidate the complex regulatory role of this nutrient, in an effort to improve patient outcomes. Vitamin D greatly contributes to the regulation of the immune system. In patients with CAAG, the immune system attacks the stomach lining; thus, the maintenance of a healthy and balanced immune response is important. In autoimmune conditions such as CAAG, where inflammation plays a decisive role in disease progression, vitamin D could potentially exert a role in managing and controlling the associated symptoms. Adequate vitamin D levels may help in regulating the immune response and reducing inflammation. In addition, patients with CAAG are at risk of nutrient deficiencies, including vitamin B12 and iron, which can lead to anemia and bone health issues. As vitamin D is critical for calcium absorption and bone health, assurance of sufficient levels of this micronutrient can be beneficial in preventing or mitigating bone-related complications. In conclusion, regular monitoring of vitamin D levels, among other nutrients, and appropriate supplementation, when necessary, can help improve overall health and well-being in these patients.

Prevalence of H. pylori and Gastric Intestinal Metaplasia in BRCA1 and BRCA2 Carriers

BRCA1 and BRCA2 carriers may be at increased risk for gastric cancer; however, the mechanisms of gastric carcinogenesis remain poorly understood. We sought to determine the prevalence of gastric cancer risk factors Helicobacter pylori (H. pylori) infection and gastric intestinal metaplasia (GIM) among BRCA1/2 carriers to gain insight into the pathogenesis of gastric cancer in this population. A total of 100 unselected BRCA1/2 carriers who underwent endoscopic ultrasound from March 2022 to March 2023 underwent concomitant upper endoscopy with nontargeted gastric antrum and body biopsies. The study population (70% women; mean age 60.1 years) included 66% BRCA2 carriers. H. pylori was detected in one (1%) individual, 7 (7%) had GIM, 2 (2%) had autoimmune atrophic gastritis, and no gastric cancers were diagnosed. Among BRCA1/2 carriers, H. pylori prevalence was low and GIM prevalence was similar to that in the general population; however, identification of H. pylori or GIM may help inform future gastric cancer risk management strategies in BRCA1/2 carriers. Prevention Relevance: Evaluating the burden of H. pylori infection and GIM among BRCA1/2 carriers is warranted to better understand the mechanisms of gastric carcinogenesis and to help inform risk management strategies for gastric cancer among this at-risk population.

Oral vitamin B12 supplementation in pernicious anemia: a prospective cohort study

BACKGROUND

The absorption of vitamin B12 is hindered in pernicious anemia (PA) owing to intrinsic factor deficiency. Traditionally, intramuscular vitamin B12 injections were the standard treatment, bypassing the impaired absorption. Although there is potential for oral vitamin B12 supplementation through passive enteral absorption, it is not commonly prescribed in PA owing to limited studies assessing its efficacy.

OBJECTIVES

We aimed to assess the efficacy of oral vitamin B12 supplementation in PA.

METHODS

We enrolled participants diagnosed with incident vitamin B12 deficiency related to PA. The diagnosis of PA was based on the presence of classical immune gastritis and of anti-intrinsic factor and/or antiparietal cell antibodies. To evaluate the vitamin B12 status, we measured total plasma vitamin B12, plasma homocysteine, and plasma methylmalonic acid (pMMA) concentration and urinary methylmalonic acid-to-creatinine ratio. Participants were treated with oral cyanocobalamin at a dosage of 1000 μg/d throughout the study duration. Clinical and biological vitamin B12 deficiency related features were prospectively and systematically assessed over the 1-y study duration.

RESULTS

We included 26 patients with vitamin B12 deficiency revealing PA. Following 1 mo of oral vitamin B12 supplementation, 88.5% of patients were no longer deficient in vitamin B12, with significant improvement of plasma vitamin B12 [407 (297-485) compared with 148 (116-213) pmol/L; P < 0.0001], plasma homocysteine [13.5 (10.9-29.8) compared with 18.6 (13.7-46.8) μmol/L; P < 0.0001], and pMMA [0.24 (0.16-0.38) compared with 0.56 (0.28-1.09) pmol/L; P < 0.0001] concentrations than those at baseline. The enhancement of these biological parameters persisted throughout the 12-month follow-up, with no patients showing vitamin B12 deficiency by the end of the follow-up period. The median time to reverse initial vitamin B12 deficiency abnormalities ranged from 1 mo for hemolysis to 4 mo for mucosal symptoms.

CONCLUSIONS

Oral supplementation with 1000 μg/d of cyanocobalamin has been shown to improve vitamin B12 deficiency in PA.

Luteolin targets the AGE-RAGE signaling to mitigate inflammation and ferroptosis in chronic atrophic gastritis

Chronic atrophic gastritis (CAG) is a chronic inflammatory disease and precancerous lesion in stomach cancer. Abnormal activation cellular ferroptosis further damages gastric tissue, which is susceptible to inflammation. Luteolin has powerful anti-inflammatory and regulatory potential for cellular ferroptosis. We aimed to clarify the involvement of luteolin in inflammation and ferroptosis during CAG. Luteolin targets were searched to identify intersecting genes in the chronic atrophic gastritis disease database. The AGE-RAGE pathway is a potential target of luteolin for the treatment of chronic atrophic gastritis and a binding site between luteolin and RAGE was predicted through a computer simulation of molecular docking. We established a CAG rat model using N-methyl-N-nitro-N-nitroguanidine. The therapeutic effect of luteolin on CAG was detected using western blotting, qPCR, hematoxylin and eosin staining, lipid oxidation (MDA), and Fe2+ assays. Luteolin inhibited the AGE-RAGE signaling pathway and reduced the inflammatory response in gastric tissues. Additionally, luteolin downregulated the concentration of (MDA) and Fe2+, and CAG downregulated the expression levels of ACSL4 and NOX1 and upregulated the expression levels of FIH1 and GPX4 ferroptosis-related proteins, thus inhibiting the ferroptosis of gastric tissue cells, which had a therapeutic effect on CAG.

Autoimmune Gastritis and Hypochlorhydria: Known Concepts from a New Perspective

Autoimmune atrophic gastritis is an immune-mediated disease resulting in autoimmune destruction of the specialized acid-producing gastric parietal cells. As a consequence, in autoimmune atrophic gastritis, gastric acid secretion is irreversibly impaired, and the resulting hypochlorhydria leads to the main clinical manifestations and is linked, directly or indirectly, to the long-term neoplastic complications of this disease. In the last few years, autoimmune atrophic gastritis has gained growing interest leading to the acquisition of new knowledge on different aspects of this disorder. Although reliable serological biomarkers are available and gastrointestinal endoscopy techniques have substantially evolved, the diagnosis of autoimmune atrophic gastritis is still affected by a considerable delay and relies on histopathological assessment of gastric biopsies. One of the reasons for the diagnostic delay is that the clinical presentations of autoimmune atrophic gastritis giving rise to clinical suspicion are very different, ranging from hematological to neurological-psychiatric up to gastrointestinal and less commonly to gynecological-obstetric symptoms or signs. Therefore, patients with autoimmune atrophic gastritis often seek advice from physicians of other medical specialties than gastroenterologists, thus underlining the need for increased awareness of this disease in a broad medical and scientific community.

Unveiling early stage autoimmune gastritis: novel endoscopic insights from two case reports

The predominant characteristic of autoimmune gastritis (AIG) is corpus-dominant advanced atrophy, which is mostly observed in the middle to late stages. More reports are needed on the endoscopic features of the early stage. In this report, we present two cases of early-stage AIG in which endoscopic examinations showed no atrophy of the gastric mucosa but displayed a transition of collecting venules from a regular to an irregular arrangement. In addition, yellowish-white cobblestone-like elevations were observed in the fundic gland region. Histologically, the observed manifestations included pseudohypertrophy and protrusion of parietal cells into the lumen, possibly along with hyperplasia of G cells, lymphocytic infiltration and potentially pseudopyloric gland metaplasia. Serologically, the anti-parietal cell antibody returned positive results, whereas the anti-intrinsic factor antibody yielded negative results. In this study, we summarized some endoscopic features of two patients, aiming to provide clues for endoscopists to detect early-stage AIG.

Clinicopathological Features of Early Gastric Cancer Complicated by Autoimmune Gastritis

INTRODUCTION

In the post-Helicobacter pylori era, autoimmune gastritis (AIG) is attracting increasing attention as an origin of gastric cancer. Here, we performed clinicopathological examination of gastric cancer complicating AIG treated in our hospital.

METHODS

Eighty-six early gastric cancer lesions complicating AIG in 50 patients were treated by endoscopic submucosal dissection (ESD) at our hospital in 2008-2022. Their clinicopathological characteristics were compared with those of a control group comprising 2,978 early gastric cancer lesions (excluding lesions in the remnant stomach after surgery) in 2,278 patients treated by ESD during the same period.

RESULTS

Mean age was significantly higher in the AIG group than in the control group (74.7 years vs. 70.9 years; p < 0.01). In the respective groups, the occurrence rate of synchronous/metachronous lesions was 38.0% and 20.4% (p < 0.01), the ratio of longitudinal cancer locations (upper/middle/lower third [U/M/L]) was 27/32/27 and 518/993/1,467 (p < 0.01), the ratio of circumferential cancer locations (lesser curvature/greater curvature/anterior wall/posterior wall) was 25/31/12/18 and 1,259/587/475/657 (p < 0.01), the ratio of major macroscopic types (I/IIa/IIb/IIc) was 13/38/5/30 and 65/881/220/1,812 (p < 0.01). The rates of multiple gastric cancer and cancers in the U region, at the greater curvature, and of protruding types were significantly higher in the AIG group.

CONCLUSION

The occurrence rate of multiple gastric cancer was significantly higher in gastric cancer complicating AIG (approximately 40%), and compared with the control group, the proportions of cancers at the U region, at the greater curvature, and of protruding types were significantly higher.

Pernicious anemia presenting with dysphagia and melanoderma: a confusing manifestation

Vitamin B12 deficiency is widely recognized as a common cause of anemia. However, symptoms such as dysphagia, melanoderma, and pancytopenia, although less frequent, can also be associated with this deficiency. We report the case of a 47-year-old Caucasian man presented with dysphagia to solids associated to high heart rate, dyspnea and melanoderma. He was diagnosed with severe anemia (hemoglobin 4 g/dl) in association with pancytopenia. Further investigation confirmed that the underlying cause was severe vitamin B12 deficiency secondary to pernicious anemia. Subsequent treatment with vitamin B12 supplements led to a significant improvement in all symptoms. A review of the existing literature corroborated the rarity of severe anemia occurring in conjunction with dysphagia and melanoderma due to B12 deficiency.

A Natural Peptide from A Traditional Chinese Medicine Has the Potential to Treat Chronic Atrophic Gastritis by Activating Gastric Stem Cells

Chronic atrophic gastritis (AG) is initiated mainly by Helicobacter pylori infection, which may progress to stomach cancer following the Correa's cascade. The current treatment regimen is H. pylori eradication, yet evidence is lacking that this treatment is effective on later stages of AG especially gastric gland atrophy. Here, using AG mouse model, patient samples, gastric organoids, and lineage tracing, this study unraveled gastric stem cell (GSC) defect as a crucial pathogenic factor in AG in mouse and human. Moreover, a natural peptide is isolated from a traditional Chinese medicine that activated GSCs to regenerate gastric epithelia in experimental AG models and revitalized the atrophic gastric organoids derived from patients. It is further shown that the peptide exerts its functions by stabilizing the EGF-EGFR complex and specifically activating the downstream ERK and Stat1 signaling. Overall, these findings advance the understanding of AG pathogenesis and open a new avenue for AG treatment.

Long-Term Natural History of Autoimmune Gastritis: Results From a Prospective Monocentric Series

INTRODUCTION

The natural history of autoimmune gastritis (AIG) has been poorly described. In this study, we report the long-term natural history and clinical clustering of the full spectrum of AIG, from the potential to the complicated stage.

METHODS

Prospective single-center study conducted in a tertiary referral center. Patients with AIG at any stage (0 = potential; 1 = early; 2 = florid; 3 = severe; and 4 = complicated) were enrolled (January 2000-December 2022). The histopathological evolution, the clinical presentation, and the correlates of evolution of potential AIG were assessed.

RESULTS

Four hundred ninety-eight patients with AIG (mean age 56.7 ± 15.2 years, F:M ratio 2.5:1) were included, of whom 93 experienced potential AIG. The maximum disease duration was 27 years (median 18, interquartile range 14-23), while the overall median follow-up was 52 months (interquartile range 12-95). Age was significantly lower in stage 0 compared with that in the other stages. Accidental histologic evidence and hematologic findings were the most common clusters of diagnosis. The overall median rate of progression was 7.29 per 100 persons/yr (95% confidence interval [CI] 6.19-8.59), while the stage-specific rates of progression were 10.85 (stage 0; 95% CI 7.75-15.18), 14.83 (stages 1-2; 95% CI 11.89-18.49), and 2.68 (stage 3; 95% CI 1.88-3.84). Newly onset neoplastic complications at follow-up occurred in 41/483 patients (8.5%; 23 neuroendocrine tumors and 18 epithelial dysplasia). No cases of adenocarcinoma were noticed. Male sex was associated with a greater likelihood of evolving from potential AIG to overt AIG.

DISCUSSION

AIG is a progressive disorder, with a virtually absent risk of gastric adenocarcinoma. Patients with potential AIG should be monitored because they carry a high risk of evolving into overt AIG.

Iron deficiency in pernicious anemia: Specific features of iron deficient patients and preliminary data on response to iron supplementation

BACKGROUND & AIMS

While vitamin B12 (B12) deficiency is considered as the hallmark of pernicious anemia (PA), iron deficiency (ID) is also prevalent. Indeed, this auto immune gastritis is responsible for parietal cell atrophy and increase in gastric pH, leading to impaired iron absorption. We compared PA patients' features according to their iron status at PA diagnosis, and we assessed the iron status recovery after oral or intravenous iron supplementation.

METHODS

We prospectively included patients presenting with a newly diagnosed PA in a tertiary referral hospital between November 2018 and October 2020. Iron status was assessed at PA diagnosis then regularly during a standardized follow-up. In case of ID, the decision of treatment with oral and/or intravenous iron supplementation was left to the clinician convenience.

RESULTS

We included 28 patients with newly diagnosed PA. ID was observed in 21/28 (75.0%) patients: from the PA diagnosis in 13 patients, or during the follow-up in 8 patients. Iron deficient PA patients had higher plasma B12 (p = 0.04) and lower homocysteine levels (p = 0.04). Also, ID was independently associated with the 'APCA (anti-parietal cell antibodies) alone' immunological status (absence of anti-intrinsic factor antibodies) after adjustment for age, gender and B12 level (aOR 12.1 [1.1-141.8], p = 0.04). High level of APCA was associated with lower ferritin level. After 3 months of supplementation, 3/11 PA patients normalized the iron status with oral iron supplementation, versus 7/8 with intravenous iron supplementation (p = 0.02).

CONCLUSION

The high frequency of iron deficiency in PA highlights the interest of regular assessment of iron status in this condition. ID was associated with a profile including APCA alone and less pronounced B12 deficiency. Intravenous iron supplementation seemed to be more efficient than an oral supplementation in these preliminary data.

RE.GA.IN.: the Real-world Gastritis Initiative-updating the updates

At the end of the last century, a far-sighted 'working party' held in Sydney, Australia addressed the clinicopathological issues related to gastric inflammatory diseases. A few years later, an international conference held in Houston, Texas, USA critically updated the seminal Sydney classification. In line with these initiatives, Kyoto Global Consensus Report, flanked by the Maastricht-Florence conferences, added new clinical evidence to the gastritis clinicopathological puzzle.The most relevant topics related to the gastric inflammatory diseases have been addressed by the Real-world Gastritis Initiative (RE.GA.IN.), from disease definitions to the clinical diagnosis and prognosis. This paper reports the conclusions of the RE.GA.IN. consensus process, which culminated in Venice in November 2022 after more than 8 months of intense global scientific deliberations. A forum of gastritis scholars from five continents participated in the multidisciplinary RE.GA.IN. consensus. After lively debates on the most controversial aspects of the gastritis spectrum, the RE.GA.IN. Faculty amalgamated complementary knowledge to distil patient-centred, evidence-based statements to assist health professionals in their real-world clinical practice. The sections of this report focus on: the epidemiology of gastritis; Helicobacter pylori as dominant aetiology of environmental gastritis and as the most important determinant of the gastric oncogenetic field; the evolving knowledge on gastric autoimmunity; the clinicopathological relevance of gastric microbiota; the new diagnostic horizons of endoscopy; and the clinical priority of histologically reporting gastritis in terms of staging. The ultimate goal of RE.GA.IN. was and remains the promotion of further improvement in the clinical management of patients with gastritis.

The mutual interactions among Helicobacter pylori, chronic gastritis, and the gut microbiota: a population-based study in Jinjiang, Fujian

Objectives

Helicobacter pylori (H. pylori) is a type of bacteria that infects the stomach lining, and it is a major cause of chronic gastritis (CG). H. pylori infection can influence the composition of the gastric microbiota. Additionally, alterations in the gut microbiome have been associated with various health conditions, including gastrointestinal disorders. The dysbiosis in gut microbiota of human is associated with the decreased secretion of gastric acid. Chronic atrophic gastritis (CAG) and H. pylori infection are also causes of reduced gastric acid secretion. However, the specific details of how H. pylori infection and CG, especially for CAG, influence the gut microbiome can vary and are still an area of ongoing investigation. The incidence of CAG and infection rate of H. pylori has obvious regional characteristics, and Fujian Province in China is a high incidence area of CAG as well as H. pylori infection. We aimed to characterize the microbial changes and find potential diagnostic markers associated with infection of H. pylori as well as CG of subjects in Jinjiang City, Fujian Province, China.

Participants

Enrollment involved sequencing the 16S rRNA gene in fecal samples from 176 cases, adhering to stringent inclusion and exclusion criteria. For our study, we included healthy volunteers (Normal), individuals with chronic non-atrophic gastritis (CNAG), and those with CAG from Fujian, China. The aim was to assess gut microbiome dysbiosis based on various histopathological features. QIIME and LEfSe analyses were performed. There were 176 cases, comprising 126 individuals who tested negative for H. pylori and 50 who tested positive defined by C14 urea breath tests and histopathological findings in biopsies obtained through endoscopy. CAG was also staged by applying OLGIM system.

Results

When merging the outcomes from 16S rRNA gene sequencing results, there were no notable variations in alpha diversity among the following groups: Normal, CNAG, and CAG; OLGIM I and OLGIM II; and H. pylori positive [Hp (+)] and H. pylori negative [Hp (-)] groups. Beta diversity among different groups show significant separation through the NMDS diagrams. LEfSe analyses confirmed 2, 3, and 6 bacterial species were in abundance in the Normal, CNAG, and CAG groups; 26 and 2 species in the OLGIM I and OLGIM II group; 22 significant phylotypes were identified in Hp (+) and Hp (-) group, 21 and 1, respectively; 9 bacterial species exhibited significant differences between individuals with CG who were Hp (+) and those who were Hp (-).

Conclusion

The study uncovered notable distinctions in the characteristics of gut microbiota among the following groups: Normal, CNAG, and CAG; OLGIM I and OLGIM II; and Hp (+) and Hp (-) groups. Through the analysis of H. pylori infection in CNAG and CAG groups, we found the gut microbiota characteristics of different group show significant difference because of H. pylori infection. Several bacterial genera could potentially serve as diagnostic markers for H. pylori infection and the progression of CG.

Prevalence of Histological Gastritis in a Community Population and Association with Epigastric Pain

BACKGROUND AND AIMS

Gastritis is a common histological diagnosis, although the prevalence is decreasing in developed populations, alongside decreasing prevalence of H. pylori infection. We sought to determine the prevalence of the etiology of gastritis in a Swedish population sample and to analyze any associations with symptoms, an area of clinical uncertainty.

METHODS

Longitudinal population-based study based in Östhammar, Sweden. A randomly sampled adult population completed a validated gastrointestinal symptom questionnaire (Abdominal Symptom Questionnaire, ASQ) in 2011 (N = 1175). Participants < 80 years of age and who were eligible were invited to undergo esophagogastroduodenoscopy (EGD) (N = 947); 402 accepted and 368 underwent EGD with antral and body biopsies (average 54.1 years, range 20-79 years; 47.8% male) with H. pylori serology.

RESULTS

Gastritis was found in 40.2% (148/368; 95% CI 35.2-45.2%). By rank, the most common histological subtype was reactive (68/148; 45.9%), then H. pylori (44/148; 29.7%), chronic non-H. pylori (29/148; 19.6%), and autoimmune (4/148; 2.7%). Gastritis was significantly associated with older age and H. pylori status (p < 0.01). Gastritis subjects were divided into three histological categories: chronic inactive inflammation, autoimmune gastritis, and active inflammation; there was no difference in the presence of upper gastrointestinal symptoms when categories were compared to cases with no pathological changes. Functional dyspepsia or gastroesophageal reflux were reported in 25.7% (38/148) of those with gastritis (any type or location) versus 34.1% (75/220) with no pathological changes (p = 0.32). Epigastric pain was more common in chronic H. pylori negative gastritis in the gastric body (OR = 3.22, 95% CI 1.08-9.62).

CONCLUSION

Gastritis is common in the population with a prevalence of 40% and is usually asymptomatic. Chronic body gastritis may be associated with epigastric pain, but independent validation is required to confirm these findings. Clinicians should not generally ascribe symptoms to histological gastritis.

Marked intestinal trans-differentiation by autoimmune gastritis along with ectopic pancreatic and pulmonary trans-differentiation

BACKGROUND

Autoimmune gastritis (AIG) is a prevalent chronic inflammatory disease with oncogenic potential that causes destruction of parietal cells and severe mucosal atrophy. We aimed to explore the distinctive gene expression profiles, activated signaling pathways, and their underlying mechanisms.

METHODS

A comprehensive gene expression analysis was conducted using biopsy specimens from AIG, Helicobacter pylori-associated gastritis (HPG), and non-inflammatory normal stomachs. Gastric cancer cell lines were cultured under acidic (pH 6.5) conditions to evaluate changes in gene expression.

RESULTS

Gastric mucosa with AIG had a unique gene expression profile compared with that with HPG and normal mucosa, such as extensively low expression of ATP4A and high expression of GAST and PAPPA2, which are involved in neuroendocrine tumorigenesis. Additionally, the mucosa with AIG and HPG showed the downregulation of stomach-specific genes and upregulation of small intestine-specific genes; however, intestinal trans-differentiation was much more prominent in AIG samples, likely in a CDX-dependent manner. Furthermore, AIG induced ectopic expression of pancreatic digestion-related genes, PNLIP, CEL, CTRB1, and CTRC; and a master regulator gene of the lung, NKX2-1/TTF1 with alveolar fluid secretion-related genes, SFTPB and SFTPC. Mechanistically, acidic conditions led to the downregulation of master regulator and stemness control genes of small intestine, suggesting that increased environmental pH may cause abnormal intestinal differentiation in the stomach.

CONCLUSIONS

AIG induces diverse trans-differentiation in the gastric mucosa, characterized by the transactivation of genes specific to the small intestine, pancreas, and lung. Increased environmental pH owing to AIG may cause abnormal differentiation of the gastric mucosa.

Differential Diagnoses and Management Approaches for Gastric Polyposis

Multiple gastric polyps are observed in various polyposis syndromes and conditions associated with polypoid lesion development in the stomach. Polyposis syndromes often occur concurrently with specific malignant tumors and can manifest at any point in an individual’s lifespan, thus explaining the diversity in surveillance methods. Furthermore, genetic counseling and surveillance are essential not only for the patients themselves but also for their blood relatives. Therefore, the accurate diagnosis and appropriate surveillance of multiple gastric polyps are crucial for improving patient outcomes. This review aims to provide essential information on such lesions along with representative endoscopic images of familial adenomatous polyposis, Peutz-Jeghers syndrome, Cowden syndrome, Cronkhite-Canada syndrome, juvenile polyposis syndrome, gastric adenocarcinoma and proximal polyposis of the stomach, neuroendocrine tumors in autoimmune gastritis, proton pump inhibitor-related gastric mucosal changes, and multiple submucosal heterotopic glands. We wish for this review to serve as a valuable resource for endoscopists seeking to deepen their comprehension of gastric polyposis.

Autoimmune gastritis

Diagnosis of autoimmune gastritis (AIG) is often challenging because of the absence of typical symptoms. Clinical guidelines are lacking, which results in inadequate treatment and poor cancer screening. This work presents an overview of current management options and aims at raising awareness for this disease. The paper also describes a clinical case of the full-scale course of AIG with all its complications. Autoimmune gastritis is mostly considered as a disease of elderly with vitamin B12 deficiency and pernicious anaemia. Today it is recognized that AIG is found with a similar prevalence in all age groups, with iron deficiency being a frequent symptom. Conventional therapy consists of adequate iron and vitamin B12 supplementation, as well as symptomatic approaches. The associated risk for gastric adenocarcinoma and gastric neuroendocrine tumours requires regular endoscopic follow-up. New treatments aiming to reduce gastric atrophy and cancer risk are currently under development. Thus, treatment of autoimmune gastritis should focus on optimizing supplementation of vitamin and macronutrient deficiencies, symptomatic therapy that improves quality of life, and include cancer prevention measures. Clinical studies should address the possibility to arrest the inflammation process and to prevent progression of AIG. The author of the article suggests that itopride hydrochloride and rebamipide will be used for symptomatic and pathogenetic therapy. The problem facing gastroenterologists today is to develop domestic guidelines for the management and screening endoscopic intervals of patients with AIG.

A puzzling case report of well-differentiated neuroendocrine tumor mixed with gastric adenocarcinoma of the fundic gland type associated with autoimmune gastritis

Gastric adenocarcinoma of the fundic gland type (GA-FG) is a rare gastric neoplasm. We present a unique case of multiple GA-FG that coexisted with the well-differentiated neuroendocrine tumors in a patient with autoimmune gastritis. To our knowledge, this is the first documented instance of such a co-occurrence and the molecular mechanism of their origin has been reviewed systematically. A 47-year-old male presented to our hospital with abdominal distension for over 10 years. Gastroscopy revealed multiple gastric eminence lesions (0.2-1.5 cm). After endoscopic mucosal resection, the pathological morphology showed mixed tumor components infiltrating into the submucosa with puzzling similarity. One with uniform-sized tumor cells arranged in nests or tubes and the other a well-differentiated tubular adenocarcinoma with irregular branching and visible gland fusion. Immunohistochemistry findings revealed the first component expressed typical markers of neuroendocrine tumor, whereas the second component expressed pepsinogen and mucin-6, indicating the presence of oxyntic gland adenocarcinoma. Due to the tumors' proximity to the surgical margins, the patient underwent laparoscopic subtotal gastrectomy three months after the diagnosis without any tumor residue and showed no recurrence or metastasis occurred in the following regular checkups.

Current understanding of pathogenetic mechanisms in neuroendocrine neoplasms

INTRODUCTION

Despite the fact that important advances in research on neuroendocrine neoplasms (NENs) have been made, consistent data about their pathogenetic mechanism are still lacking. Furthermore, different primary sites may recognize different pathogenetic mechanisms.

AREAS COVERED

This review analyzes the possible biological and molecular mechanisms that may lead to NEN onset and progression in different organs. Through extensive research of the literature, risk factors including hypercholesterolemia, inflammatory bowel disease, chronic atrophic gastritis are evaluated as potential pathogenetic mechanisms. Consistent evidence is available regarding sporadic gastric NENs and MEN1 related duodenopancreatic NENs precursor lesions, and genetic-epigenetic mutations may play a pivotal role in tumor development and bone metastases onset. In lung neuroendocrine tumors (NETs), diffuse proliferation of neuroendocrine cells on the bronchial wall (DIPNECH) has been proposed as a premalignant lesion, while in lung neuroendocrine carcinoma nicotine and smoke could be responsible for carcinogenic processes. Also, rare primary NENs such as thymic (T-NENs) and Merkel cell carcinoma (MCC) have been analyzed, finding different possible pathogenetic mechanisms.

EXPERT OPINION

New technologies in genomics and epigenomics are bringing new light to the pathogenetic landscape of NENs, but further studies are needed to improve both prevention and treatment in these heterogeneous neoplasms.

Gastrointestinal conditions in the multiple sclerosis prodrome

OBJECTIVE

To investigate gastrointestinal (GI)-related physician visits and drug dispensations in the 5 years preceding a first recorded demyelinating event or multiple sclerosis (MS) onset.

METHODS

Using linked administrative and clinical data from British Columbia (1996-2013), Canada, we identified an administrative cohort via a validated algorithm (n = 6863), a clinical cohort diagnosed at a MS clinic (n = 966), and matched controls (administrative cohort: n = 31,865; clinical cohort: n = 4534). In each cohort, the 5 years before a first demyelinating event or MS symptom onset (i.e., index date) were examined. We compared rates of GI-related physician visits and risk of ≥1 GI-related dispensation between MS cases and controls using negative binomial and robust Poisson models. Sex differences were tested using interaction terms.

RESULTS

The administrative cohort MS cases had higher rates of physician visits related to gastritis and duodenitis (adjusted rate/risk ratio (aRR):1.42, 95% CI: 1.10-1.83) and diseases of the esophagus (aRR: 1.46, 95% CI: 1.06-2.02) prior to the index date. MS cases also had greater risk of at least one dispensation for several drug classes, including constipation-related (aRR: 1.82, 95% CI: 1.50-2.22), antiemetics/antinauseants (aRR: 1.64, 95% CI: 1.43-1.89), and propulsives (promotility drugs; aRR: 1.62, 95% CI: 1.47-1.79). Men had a disproportionally higher relative risk for propulsives than women (aRR: men = 2.32, 95% CI: 1.79-3.00; women = 1.54, 95% CI: 1.36-1.72). Several findings were similar in the smaller clinical cohort though none reached statistical significance.

INTERPRETATION

GI-related physician visits and drug dispensations were more common in the 5 years before the first demyelinating event versus matched controls. GI symptoms are a measurable feature of the prodromal or early phase of MS, with a sex difference evident.

A novel telomere biology disease-associated gastritis identified through a whole exome sequencing-driven approach

A whole exome sequencing (WES)-driven approach to uncover the etiology of unexplained inflammatory gastritides has been underutilized by surgical pathologists. Here, we discovered the pathobiology of an unusual chronic atrophic gastritis in two unrelated patients using this approach. The gastric biopsies were notable for an unusual pattern of gastritis with persistent dense inflammation, loss of both parietal and neuroendocrine cells in the oxyntic mucosa, and sparing of the antral mucosa. The patients were found to harbor pathogenic variants in telomeropathic genes (POT1 and DCLRE1B). Clonality testing for one of the patients showed evidence of evolving clonality of TCR-gene rearrangement. Both patients showed significantly decreased numbers of stem/progenitor cells by immunohistochemistry, which appears to be responsible for the development of mucosal atrophy. No such cases of unusual chronic atrophic gastritis in the setting of telomeropathy have been previously reported. The loss of stem/progenitor cells suggests that stem/progenitor cell exhaustion in the setting of telomere dysfunction is the likely mechanism for development of this unusual chronic atrophic gastritis. The results underscore the need for close monitoring of these gastric lesions, with special regard to their neoplastic potential. This combined WES-driven approach has promise to identify the cause and mechanism of other uncharacterized gastrointestinal inflammatory disorders.