Chronic Autoimmune Gastritis: Modern Diagnostic Principles

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.

Autoimmune gastritis diagnosed due to recurrent gastric neuroendocrine tumor: a case report

As digestive endoscopy becomes more prevalent, an increasing number of autoimmune gastritis (AIG) cases have been diagnosed, which has contributed to a growing body of research on AIG. We report the case of a patient with AIG who was diagnosed due to receiving endoscopic surgery after discovering a gastric neuroendocrine tumor (GNET) during gastroscopy twice within 3 years. The patient was admitted to our hospital for endoscopic submucosal dissection (ESD) due to GNET recurrence discovered during gastroscopy. The patient had previously undergone ESD due to a GNET discovered during gastroscopy 3 years ago. Recent repeat gastroscopy revealed severe mucosal atrophy in the gastric body and fundus, an ulcer in the gastric antral, and two mucosal bulges in the gastric body. Pathology indicated Grade 2 (G2)-GNET, and ESD was performed again. The patient also had iron deficiency anemia and thyroid dysfunction, elevated gastrin, and decreased pepsinogen I (PG I) and PG I/II. Hence, AIG was diagnosed. Recurrent GNET cases, especially those with concurrent anemia and abnormal thyroid function, may experience AIG. In addition to symptomatic treatment, the clinician must evaluate the patient's overall condition.

H. pylori-Associated Gastritis, Gastritis after H. pylori Eradication and H. pylori-Negative Gastritis: Algorithm of Diagnosis and Treatment (Literature Review and Resolution of the Expert Panel of the Russian Gastroenterological Association)

Aim: to provide the basic points of the Expert Panel of the Russian Gastroenterological Association with discussion of measures to improve diagnostics, treatment and management of chronic gastritis patients.

Key points. In the Russian Federation in 2021 more than 30 million patients diagnosed with “Gastritis and duodenitis” were recorded (K29 in accordance with International Classification of Diseases-10). H. pylori incidence rate in the Russian population has reduced and presently is about 40 %. In chronic gastritis pattern H. pylori-associated gastritis has still dominated though gastritis percent after successful H. pylori eradication, reactive gastropathy (including reflux gastritis) and autoimmune gastritis, has increased. Endoscopic and histologic examinations serve as key diagnostic techniques that provide a means for assessing the ethiology of gastritis, topography and degree of atrophic changes, gastritis staging as per OLGA/OLGIM system that properly correlates with the risk of stomach cancer and determines endoscopic examination strategy. H. pylori eradication therapy of gastritis serves as an etiotropic treatment and makes it possible to prevent progression of atrophy and stomach cancer. Conventional triple therapy combined with bismuth tripotassium dicitrate allows for achieving optimal cure rates of H. pylori eradication. Addition of rebamipide to regimens of H. pylori eradication improves their efficiency. Rebamipide arrests symptoms of dyspepsia in the case of chronic gastritis and functional dyspepsia. The administration of rebamipide for chronic gastritis makes it possible to influence the syndrome of increased epithelial permeability and inflammation, which makes it advisable to study it as a means of preventing stomach cancer and the progression of atrophy in various types of chronic gastritis.

Conclusion. Members of the Expert Panel has approved the algorithm of diagnosis and treatment of H. pylori-associated gastritis, gastritis after H. pylori eradication and H. pylori-negative gastritis at the diagnostic stage in the case of initial presentation and long-term follow-up when needed.

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.

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.

Coexistence of Guillain-Barré Syndrome and Subacute Combined Degeneration of the Spinal Cord Due to Autoimmune Gastritis: A Case Report and Literature Review

Guillain-Barré syndrome (GBS) and autoimmune gastritis (AIG) are both autoimmune diseases (ADs) that have a low prevalence in China. Both conditions involve the immune system mistakenly attacking the body's own tissues. GBS primarily affects the peripheral nervous system, leading to muscle weakness and paralysis, while AIG targets the stomach lining, causing inflammation and reduced absorption of vital nutrients. Subacute combined degeneration (SCD) of the spinal cord is the most common neurological manifestation of vitamin B12 deficiency. As of yet, there have been no reported cases of patients with GBS and complications of AIG including SCD. We report a case of a 54-year-old male patient who had been experiencing progressive numbness and weakness in his extremities, burning and tingling sensations, a cotton-stepping sensation, and difficulty walking for three weeks. He was admitted to the hospital and underwent an extensive medical workup. Magnetic resonance imaging (MRI) of the cervical spine cord showed abnormal spinal cord signal intensity consistent with typical manifestations of vitamin B12 deficiency. Gastric endoscopy revealed local atrophy of the gastric corpus, and gastric tissue biopsy indicated atrophic gastritis with intestinal metaplasia, consistent with a diagnosis of AIG. Lumbar puncture of cerebrospinal fluid (CSF) results showed albumincytological dissociation, further confirming the diagnosis of GBS. He was treated with intravenous immunoglobulin and methylcobalamin therapy for these conditions and showed significant clinical improvement upon discharge.

Treatment with IgG Fc fragments bearing regRF epitopes prevents destruction of the gastric mucosa in experimental autoimmune gastritis model

Autoimmune gastritis (AIG) is the autoimmune disease of the stomach characterized by the destruction of the oxyntic mucosa, which stops producing acid and becomes both functionally and morphologically atrophic. There is no specific treatment for AIG. Previously, we identified a new immunoregulatory factor (regulatory rheumatoid factor (regRF)), the stimulation production of which reduces certain experimental autoimmune diseases. Epitopes specific to the regulatory rheumatoid factor (regRF epitopes) can be obtained on IgG Fc fragments. In the rat AIG model, the therapeutic efficacy of IgG Fc fragments bearing regRF epitopes was tested. Treatment with IgG Fc fragments bearing regRF epitopes reduced T lymphocytic infiltration of oxyntic mucosa and prevented its damage in the AIG rat model, while in rats treated with placebo, T lymphocytic infiltration of the mucosa, loss of parietal cells, including severe were observed. Therefore, IgG Fc fragments bearing regRF epitopes are a potential therapeutic agent for treating autoimmune gastritis in its early stages.

Rat Experimental Autoimmune Gastritis Model

BACKGROUND

Autoimmune gastritis (AIG) is an autoimmune disease of the stomach characterized by the destruction of the oxyntic mucosa, which stops producing acid and becomes both functionally and morphologically atrophic. The pathogenic mechanisms behind the disease are still poorly understood. There is no early diagnosis and specific AIG therapy. To elucidate the pathogenesis of AIG, to search for early diagnostic markers, as well as to test new therapeutic approaches, an adequate and easily reproducible experimental model for autoimmune gastritis (EAG) is needed. Existing EAG models have some limitations, including slow development of signs, absence of advanced gastritis, irrational use of animals to obtain antigen. The aim was to find out whether it is possible to cause autoimmune gastritis similar to human disease in Wistar rats through immunization with a homologous gastric mucosa extract.

METHODS

Wistar rats were immunized with gastric mucosa extract. Histology studies and evaluation of serological parameters were performed 56 and 91 days later.

RESULTS

Destruction of oxyntic glands by infiltrating T lymphocytes were detected in rats on 56 and 91 days after initial immunization with gastric mucosa extract. Hyperplasia of enterochromaffin-like (ECL) cells was detected on the 91st day. Antral mucosa remained unchanged.

CONCLUSION

Wistar rats, immunized with gastric mucosa extract, developed EAG similar to human AIG. The advantages of received EAG model are the ease of obtaining, the rapid development of oxyntic mucosa damage, which may progress to ECL cell hyperplasia.

The Impact of the Angulus Biopsy on the Detection of Staging and the Grading of Chronic Gastritis

There is a generally recognized need for a morphological assessment of the individual risk of developing gastric cancer in a patient with chronic gastritis, according to the OLGA system (Operative Link for Gastritis Assessment). At the same time, the role of assessing the biopsy from the incisura angularis remains controversial. The aim of our study was to assess the value of incisura angularis biopsy in staging gastritis according to the OLGA system by examining the atrophic and inflammatory changes in the antrum, incisura angularis, and body.

MATERIALS AND METHODS

A total of 718 patients (576 women and 142 men) aged 20 to 84 years were examined. Most of the patients were in the age group of 50 to 70 years (54.6%). Depending on the detection of H. pylori and autoimmune gastritis markers, all patients were divided into three groups. The first group included 380 patients with H. pylori gastritis without signs of autoimmune gastritis. The second group consisted of 209 patients with autoimmune gastritis, in whom no infection was detected during the examination, and there were no indications of H. pylori eradication. The third group consisted of 129 patients with chronic gastritis of combined etiology (autoimmune and H. pylori). Endoscopy biopsies were taken according to the updated Sydney System. Histological assessments of the grade and the stage of gastritis were carried out according to the standard OLGA-based protocol. Then, the same assessments were evaluated without taking into account histological changes in the incisura angularis.

RESULTS

When assessing the severity of inflammatory changes in the gastric mucosa according to the OLGA system, grade II (72.3%) was most often detected in all groups of patients. A severe degree of activity of chronic gastritis was most often observed in the group of patients with H. pylori gastritis (6.1%). These indicators practically did not change if the assessment did not take the angulus biopsy into account. When assessing the severity of atrophy of the glands in the gastric mucosa in patients of the first group, mild stages of atrophy prevailed. Without taking into account the angulus biopsy, a decrease in the stage of atrophy was observed in 27 cases (7.11%), and in only 4 cases did stage IV change to stage III, while in 23 cases, discrepancies were noted only within groups with a mild stage of atrophy. There were no transitions from stage III to stage II. In the group of patients with autoimmune gastritis, pronounced stages of atrophy prevailed-in more than 77%. Without taking into account the angulus biopsy, a decrease in the stage of atrophy was observed in eight cases (3.83%), and in three (1.4%) patients, stage III was changed to stage II. In the group of patients with combined etiology (autoimmune + H. pylori), severe stages of atrophy also prevailed (70.5%). A decrease in the stage of atrophy without taking into account the angulus biopsy was only observed in three patients (2.32%), of which two cases concerned patients with mild stages of atrophy. Thus, in general, severe stages of atrophy of the gastric mucosa (stages III and IV according to the OLGA staging system) were detected in 313 patients (43.59%). If the assessment of the atrophy stage did not take into account changes in the angulus biopsy, then severe stages of atrophy (III and IV according to OLGA) were detected in 310 patients (43.17%). In total, changes in the assessment of the atrophy stage occurred in 38 patients (5.29%), and this was more often observed in patients with stages I and II of atrophy.

CONCLUSIONS

Accounting for histological changes in the incisura angularis does not significantly affect the assessment of the grade and stage of chronic gastritis according to the OLGA system, regardless of the etiology of atrophic gastritis.

A Comprehensive Review of Upper Gastrointestinal Symptom Management in Autoimmune Gastritis: Current Insights and Future Directions

Autoimmune gastritis is characterized by inflammation of the gastric mucosa due to autoimmune dysregulation. Upper gastrointestinal symptoms associated with autoimmune gastritis can significantly impact an individual's quality of life and require effective management strategies. This review article provides a comprehensive overview of the current understanding of upper gastrointestinal symptom management in autoimmune gastritis, aiming to consolidate existing knowledge, identify gaps, and offer insights for future research and clinical practice. The review begins by discussing the background and significance of autoimmune gastritis, highlighting its prevalence and the impact of upper gastrointestinal symptoms on affected individuals. The pathophysiology and clinical presentation of autoimmune gastritis-related upper gastrointestinal symptoms are explored, emphasizing the need for accurate diagnosis and targeted management approaches. Diagnostic approaches, including diagnostic criteria, endoscopy, histology, and biomarkers, are critically examined, along with the challenges and limitations associated with diagnosing autoimmune gastritis. The review then delves into the pharmacological approaches for symptom relief, such as proton pump inhibitors (PPIs) and H2 receptor antagonists. It explores the role of dietary modifications and lifestyle changes in symptom control. The article further discusses recent advancements in pharmacological interventions, novel therapeutic approaches, and the potential benefits of complementary and alternative medicine in symptom management. The concept of patient-centered approaches and personalized management strategies is emphasized, highlighting the importance of considering individual patient characteristics, treatment goals, and preferences. Recommendations for future research and clinical management are provided, including exploring emerging therapeutic targets, precision medicine approaches, and collaboration among researchers, clinicians, and patient advocacy groups. The review concludes by emphasizing the significance of implementing the findings and recommendations in clinical practice to enhance patient care and improve the quality of life for individuals with autoimmune gastritis.

Histopathological Evaluation of Gastric Mucosal Atrophy for Predicting Gastric Cancer Risk: Problems and Solutions

Patients suffering from chronic gastritis and developing gastric mucosa atrophy are at increased risk of the development of gastric cancer. The diagnosis of chronic atrophic gastritis (CAG) is a complex procedure involving a detailed history taking, a thorough physical examination and the use of laboratory and instrumental diagnostic methods among which the endoscopy of the upper digestive tract is the cornerstone because it allows the assessment of the topography of gastritis and identification of erosions and areas of intestinal metaplasia with the use of NBI endoscopy. However, the diagnosis of CAG requires morphological examination of the gastric mucosa. So, in addition to assessing macroscopic changes in the gastric mucosa, it is necessary to take biopsy specimens in accordance with the protocols for their morphological and immunohistochemical examination. In the absence of specific diagnostic stigmas of CAG, close cooperation between a clinician, endoscopist and pathologist is necessary. The article presents systematized data on the histopathological assessment of the gastric mucosa atrophy to predict the risk of gastric cancer.

Clinical supervision of chronic atrophic gastritis

Patients with chronic gastritis (CG) with the development of atrophy of the gastric mucosa are at an increased risk of developing gastric cancer (GC). In the management of such patients, the development of high-grade dysplasia and invasive gastric cancer should be defined as adverse outcomes that must be prevented. To this end, patients with a diagnosis of «Chronic atrophic fundic/multifocal gastritis» are subject to dynamic dispensary observation to assess the achievement of target indicators, take into account information about changes in the diagnosis and concomitant diseases, emerging complications, as well as to enter data on ongoing therapeutic and preventive measures. This article presents the main aspects of prevention and dispensary monitoring of patients with an increased risk of gastric cancer.

Update in Molecular Aspects and Diagnosis of Autoimmune Gastritis

Recent studies have advanced our understanding of the pathophysiology of autoimmune gastritis, particularly its molecular aspects. The most noteworthy recent advancement lies in the identification of several candidate genes implicated in the pathogenesis of pernicious anemia through genome-wide association studies. These genes include PTPN22, PNPT1, HLA-DQB1, and IL2RA. Recent studies have also directed attention towards other genes such as ATP4A, ATP4B, AIRE, SLC26A7, SLC26A9, and BACH2 polymorphism. In-depth investigations have been conducted on lymphocytes and cytokines, including T helper 17 cells, interleukin (IL)-17A, IL-17E, IL-17F, IL-21, IL-19, tumor necrosis factor-α, IL-15, transforming growth factor-β1, IL-13, and diminished levels of IL-27. Animal studies have explored the involvement of roseolovirus and H. pylori in relation to the onset of the disease and the process of carcinogenesis, respectively. Recent studies have comprehensively examined the involvement of autoantibodies, serum pepsinogen, and esophagogastroduodenoscopy in the diagnosis of autoimmune gastritis. The current focus lies on individuals demonstrating atypical presentations of the disease, including those diagnosed in childhood, those yielding negative results for autoantibodies, and those lacking the typical endoscopic characteristics of mucosal atrophy. Here, we discuss the recent developments in this field, focusing on genetic predisposition, epigenetic modifications, lymphocytes, cytokines, oxidative stress, infectious agents, proteins, microRNAs, autoantibodies, serum pepsinogen, gastrin, esophagogastroduodenoscopy and microscopic findings, and the risk of gastric neoplasm.

Type-1 Grade 2 Multi-Focal Gastric Neuroendocrine Tumors Secondary to Chronic Autoimmune Gastritis

Background

Chronic autoimmune gastritis (CAG) refers to chronic atrophic gastritis due to autoimmunity. Loss of gastric glands in CAG results in hypergastrinemia and achlorhydria leading to Vitamin B12 deficiency and hyperplasia of G cells and enterochromaffin-like (ECL) cells. Vitamin B12 deficiency could cause pernicious anemia and subacute combined degeneration, while G cells and ECL cells hyperplasia might develop gastric neuroendocrine tumor (G-NET).

Case Presentation

A 35-year-old Chinese female presented with multi-focal type-1 Grade 2 (G2) NETs with a 14-year history of pernicious anemia and subacute combined degeneration.

Conclusion

Here, we report a rare case of a Chinese patient presenting G-NET combined with pernicious anemia and subacute combined degeneration, which are secondary to chronic autoimmune gastritis. This case also illustrates the importance of routine gastroscopy in patients with Vitamin B12 deficiency.

Characterization of Gastric Tissue-Resident T Cells in Autoimmune and Helicobacter pylori-Associated Gastritis

Data regarding the in-depth surface marker profiles of gastric tissue-resident lymphocytes in autoimmune and Helicobacter pylori-associated gastritis are lacking. In this study, we investigated potential differences in lymphocyte composition between these profiles. We enrolled patients with autoimmune (n = 14), active (current infection of H. pylori in the stomach; n = 10), and inactive gastritis (post-eradication of H. pylori; n = 20). Lymphocytes were isolated from the greater curvature of the stomach and lesser curvature of the body and analyzed using flow cytometry. The CD8+/CD3+ and CD4+/CD3+ ratios differed between the samples. Body CD4+/antrum CD4+, which is calculated by dividing the CD4+/CD3+ ratio in the body by that in the antrum, was significantly higher in autoimmune gastritis (3.54 ± 3.13) than in active (1.47 ± 0.41) and inactive gastritis (1.42 ± 0.77). Antrum CD8+/CD4+ in autoimmune gastritis (7.86 ± 7.23) was also higher than that in active (1.49 ± 0.58) and inactive gastritis (2.84 ± 2.17). The area under the receiver operating characteristic curve of antrum CD8+/CD4+ was 0.842, and the corresponding optimal cutoff point was 4.0, with a sensitivity of 71.4% and a specificity of 93.3%. We propose that an antrum CD8+/CD4+ ratio > 4.0 is a potential diagnostic marker for autoimmune gastritis.