A case of nodular gastritis progression to autoimmune gastritis after 10 years of Helicobacter pylori eradication

A 61-year-old female patient underwent upper gastrointestinal endoscopy, which confirmed the presence of Helicobacter pylori (H. pylori)-positive nodular gastritis (NG). Routine upper gastrointestinal endoscopy after H. pylori eradication revealed atrophic changes of the corpus, having gradually progressed over the 10 years after successful eradication. Serological and biopsy specimen examination showed hypergastrinemia (1200 pg/mL), positive anti-parietal cell antibody (with a titer of more 160), and endocrine cell micronests after 11 years of H. pylori eradication. The patient was diagnosed with autoimmune gastritis (AIG) based on endoscopic, serological, and histological findings. This is the first report of AIG diagnosed in a patient with NG over a long period of time after H. pylori eradication.

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.

Impact of autoimmune gastritis on chronic urticaria in paediatric patients - pathophysiological point of views

We would like to provide an updated comprehensive perspective and identify the components linked to chronic spontaneous urticaria (CSU) without specific triggers in autoimmune atrophic gastritis (AAG). AAG is an organ-specific autoimmune disease that affects the corpus-fundus gastric mucosa. Although we lack a unified explanation of the underlying pathways, when considering all paediatric patients reported in the literature, alterations result in gastric neuroendocrine enterochromaffin-like (ECL) cell proliferation and paracrine release of histamine. Several mechanisms have been proposed for the pathogenesis of CSU, with much evidence pointing towards AAG and ECL cell responses, which may be implicated as potential factors contributing to CSU. The excessive production/release of histamine into the bloodstream could cause or trigger exacerbations of CSU in AAG, independent of Helicobacter pylori; thus, the release of histamine from ECL cells may be the primary modulator.

CONCLUSION

Considering the understanding of these interactions, recognising the respective roles of AAG in the pathogenesis of CSU may strongly impact the diagnostic workup and management of unexplained/refractory CSU and may inform future research and interventions in the paediatric population.

WHAT IS KNOWN

• Autoimmune atrophic gastritis is a chronic immune-mediated inflammatory disease characterised by the destruction of the oxyntic mucosa in the gastric body and fundus, mucosal atrophy, and metaplastic changes. • Autoimmune atrophic gastritis in paediatric patients is important because of the poor outcome and risk of malignancy and possibly underestimated entities primarily reported in single-case reports.

WHAT IS NEW

• Upper gastrointestinal inflammatory disorders, independent of H. pylori, have been implicated as potential inducing factors in the development of chronic spontaneous urticaria. • If a paediatric patient presents with symptoms such as anaemia, reduced vitamin B12 levels, recurrent urticaria with no other detectable aetiology, positive anti-parietal cell antibodies, and elevated gastrin levels, autoimmune atrophic gastritis should be considered a possible cause of chronic urticaria.

Iron and Vitamin B12 Deficiency in Patients with Autoimmune Gastritis and Helicobacter pylori Gastritis: Results from a Prospective Multicenter Study

INTRODUCTION

Iron and vitamin B12 deficiencies are common in patients with atrophic gastritis, but there are limited data on the prevalence of these deficiencies in different types of atrophic gastritis.

METHODS

This multicenter, prospective study assessed micronutrient concentrations in histologically confirmed autoimmune gastritis (AIG, n = 45), Helicobacter pylori-related non-autoimmune gastritis (NAIG, n = 109), and control patients (n = 201). A multivariate analysis was performed to determine factors influencing those deficiencies.

RESULTS

The median vitamin B12 concentration was significantly lower in AIG (367.5 pg/mL, Q1, Q3: 235.5, 524.5) than in NAIG (445.0 pg/mL, Q1, Q3: 355.0, 565.0, p = 0.001) and control patients (391.0 pg/mL, Q1, Q3: 323.5, 488.7, p = 0.001). Vitamin B12 deficiency was found in 13.3%, 1.5%, and 2.8% of AIG, NAIG, and control patients, respectively. Similarly, the median ferritin concentration was significantly lower in AIG (39.5 ng/mL, Q1, Q3: 15.4, 98.3 ng/mL) than in NAIG (80.5 ng/mL, Q1, Q3: 43.6, 133.9, p = 0.04) and control patients (66.5 ng/mL, Q1, Q3: 33.4, 119.8, p = 0.007). Iron deficiency and iron deficiency adjusted to CRP were present in 28.9% and 33.3% of AIG, 12.8% and 16.5% of NAIG, and 12.9% and 18.4% of controls, respectively. Multivariate analysis demonstrated that AIG patients had a higher risk of developing vitamin B12 deficiency (OR: 11.52 [2.85-57.64, p = 0.001]) and iron deficiency (OR: 2.92 [1.32-6.30, p = 0.007]) compared to control patients. Factors like age, sex, and H. pylori status did not affect the occurrence of vitamin B12 or iron deficiency.

CONCLUSION

Iron and vitamin B12 deficiencies are more commonly observed in patients with AIG than in those with NAIG or control patients. Therefore, it is essential to screen for both iron and vitamin B12 deficiencies in AIG patients and include the treatment of micronutrient deficiencies in the management of atrophic gastritis patients.

Research status and hotspots of autoimmune gastritis: A bibliometric analysis

BACKGROUND

As an emerging potential risk factor for gastric cancer, autoimmune gastritis (AIG) has garnered increasing attention from researchers.

AIM

To analyze the research overview and popular topics in the field of AIG using bibliometrics.

METHODS

Relevant publications on AIG in the Web of Science Core Collection were collated, and data visualization and analysis of the number of publications, countries, institutions, journals, authors, keywords, and citations were performed using software such as VOSviewer, CiteSpace, and Scimago Graphic.

RESULTS

In total, 316 relevant articles were included in the analysis. From 2015 to 2022, the number of publications increased annually. The countries, institutions, authors, and journals with the highest number of publications in this field were Italy, Monash University, Toh BH, and Internal Medicine. The main keywords used in this field of research were pathogenesis, Helicobacter pylori, autoantibody, parietal cell antibody, atrophic gastritis, classification, diagnosis, autoimmune disease, risk, cancer, gastric cancer, vitamin B12 deficiency, and pernicious anemia. The following directions may be popular for future research: (1) The role of Helicobacter pylori in the pathogenesis of AIG; (2) diagnostic criteria for AIG and reference values for serum antibodies; (3) comorbidity mechanisms between AIG and other autoimmune diseases; (4) specific risks of AIG complicating gastric and other cancers; and (5) the role of vitamin B12 supplementation in patients with early-stage AIG.

CONCLUSION

This bibliometric analysis reported on popular topics and emerging trends in AIG, with diagnosis and prognosis being research hotspots in this field.

Exploring the spectrum of incidental gastric polyps in autoimmune gastritis

BACKGROUND

Gastric polyps represent an abnormal proliferation of the gastric mucosa. Chronic atrophic autoimmune gastritis (CAAG) targets parietal cells and results in hypo-achlorhydria and hypergastrinemia, which exerts a proliferative effect on the gastric mucosa.

AIMS

We investigate the incidence of gastric polyps in CAAG patients.

METHODS

This is a single-center retrospective study examining patients with confirmed CAAG from January 1990 until June 2022. Demographic, clinical, biochemical, and serological data were collected for each included patient. The histopathological characteristics of the detected polyps were recorded.

RESULTS

A total of 176 CAAG patients were included. Eighty-nine (50.5%) had 163 incidental polyps. Seventy-six patients (85%) had 130 non-endocrine lesions, among which 118 (90.7%) were inflammatory, 6 (4.6%) adenomatous, and 4 (3%) fundic; 33 patients (37%) had gastric neuroendocrine neoplasms (gNENs), and 21 (23.6%) both; one had MALToma and one gastric adenocarcinoma. Higher circulating levels of gastrin and chromogranin A were observed among patients with polyps (median 668 vs 893 pg/ml p = 0.0237, 146 vs 207 ng/ml p = 0.0027, respectively).

CONCLUSION

CAAG implies a high incidence of gNENs and exocrine lesions. Gastrin plays a possible trophic role on the mucosa. Further evidence is needed to validate its predictive role for increased polyp risk in CAAG.

Incidence and prevalence of gastric neuroendocrine tumors in patients with chronic atrophic autoimmune gastritis

BACKGROUND

The incidence of type I gastric neuroendocrine neoplasms (gNENs) has increased significantly over the past 50 years. Although autoimmune gastritis (AIG) increases the likelihood of developing gNENs, the exact incidence and prevalence of this association remain unclear.

AIM

To evaluate the incidence and prevalence of type I gNENs in a cohort of patients with a histological diagnosis of AIG.

METHODS

Patients with a histological diagnosis of AIG were enrolled between October 2020 and May 2022. Circulating levels of CgA and gastrin were assessed at enrollment. Included patients underwent regular endoscopic follow-up to detect gastric neoplastic lesions, enterochromaffin-like (ECL) cell hyperplasia, and the development of gNEN.

RESULTS

We included 176 patients [142 women (80.7%), median age 64 years, interquartile range (IQR) 53-71 years] diagnosed with AIG between January 1990 and June 2022. At enrollment. One hundred and sixteen patients (65.9%) had ECL hyperplasia, of whom, 29.5% had simple/linear, 30.7% had micronodular, and 5.7% had macronodular type. The median follow-up time was 5 (3-7.5) years. After 1032 person-years, 33 patients developed a total of 50 type I gNENs, with an incidence rate of 0.057 person-years, corresponding to an annual cumulative incidence of 5.7%. Circulating CgA levels did not significantly differ between AIG patients who developed gNENs and those who did not. Conversely, gastrin levels were significantly higher in AIG patients who developed gNENs [median 992 pg/mL IQR = 449-1500 vs 688 pg/mL IQR = 423-1200, P = 0.03]. Calculated gastrin sensitivity and specificity were 90.9% and 1.4%, respectively, with an overall diagnostic accuracy of 30% and a calculated area under the gastrin receiver operating characteristic curve (AUROC or AUC) of 0.53.

CONCLUSION

Type I gNENs are a significant complication in AIG. Gastrin's low diagnostic accuracy prevents it from serving as a marker for early diagnosis. Effective strategies for early detection and treatment are needed.

Clinicopathological characteristics of autoimmune gastritis: A single-center retrospective study

BACKGROUND AND AIM

Autoimmune gastritis (AIG) is a prominent risk factor for pernicious anemia (PA) and gastric neoplasia. This study aimed to investigate the clinicopathological characteristics of AIG patients in China, with a focus on those who had positive anti-intrinsic factor antibodies (AIFA).

METHODS

A total of 103 AIG patients who were diagnosed between January 2018 and August 2022 were reviewed in a large academic tertiary teaching hospital. Patients were divided into two groups based on the presence or absence of AIFA, and their serologic and histopathological characteristics were analyzed.

RESULTS

The mean age of the 103 AIG patients was 54.16±11.92 years (range 23-79), with 69 (66.99%) being women. AIFA were present in 28.16% of patients. Patients with AIFA-positive had a higher risk of PA than those with AIFA-negative, as demonstrated by a larger mean corpuscular volume (MCV), lower hemoglobin level, and lower vitamin B-12 level (P<0.05). There were no statistically significant differences in gastric histopathology, gastrin level, and pepsinogen level when patients were divided into AIFA-positive and AIFA-negative group. Of the 103 cases, 34 (33.01%) were concomitant with other autoimmune diseases, with autoimmune thyroid diseases being the most common (25.24%, 26/103). Thyroid peroxidase antibody, which accounted for 45.45% (25/55), was the most prevalent thyroid antibody, followed by anti-thyroglobulin antibody (34.55%, 19/55), thyroid stimulating antibody (12.73%, 7/55), and thyrotropin receptor antibody (3.64%, 2/55).

CONCLUSION

This study highlights the increased risk of severe anemia in AIFA-positive AIG patients, particularly for PA. Clinicians should consider the presence of AIFA as a warning sign for PA and prioritize early diagnosis and appropriate treatment to prevent serious complications.

Autoimmune gastritis as an unexpected cause of diarrhea in a young adult with type I diabetes: a case report

BACKGROUND

Type 1 diabetes mellitus (T1DM) is a lifelong diagnosis that involves immune-mediated damage of pancreatic beta cells and subsequent hyperglycemia, manifesting as: polyuria, polydipsia, polyphagia, and weight loss. Treatment of type 1 diabetes centers on insulin administration to replace or supplement the body's own insulin with the goal of achieving euglycemia and preventing or minimizing complications. Patients with T1DM are at risk for developing other autoimmune conditions, most commonly thyroid or celiac disease.

CASE PRESENTATION

A 20-year-old African American female with T1DM was referred by her endocrinologist to pediatric gastroenterology for 2 months of nocturnal, non-bloody diarrhea, left lower quadrant pain, and nausea; she was also being followed by neurology for complaints of lower extremity paresthesias and pain. The patient's initial lab-workup was remarkable for a low total Immunoglobulin A (IgA) level of < 6.7 mg/dL. As IgA deficiency is associated with an increased risk of celiac disease, the patient underwent upper and lower endoscopy, which was grossly unremarkable; however, histology revealed a pattern consistent with autoimmune gastritis. Subsequent serum evaluation was remarkable for an elevated fasting gastrin level and an elevated parietal cell antibody level without macrocytic anemia, iron deficiency, or vitamin B12 depletion. The patient was diagnosed with autoimmune gastritis (AIG) and subsequently initiated on parenteral B12 supplementation therapy with improvement in her neurologic and gastrointestinal symptoms.

CONCLUSION

This case illustrates the importance of recognition of red flag findings in a patient with known autoimmune disease. Following well-established health maintenance recommendations for individuals with T1DM ensures that common comorbidities will be detected. Autoimmune gastritis, while a rarer pathology in the pediatric population, deserves consideration in patients with pre-existing autoimmune conditions and new gastrointestinal or neurologic symptoms, as AIG can be associated with poor outcomes and risk of malignancy. Initial lab findings associated with an eventual diagnosis of AIG typically include anemia, iron deficiency, or Vitamin B12 deficiency. However, as demonstrated in this case, symptoms of AIG can rarely present before anemia or Vitamin B12 deficiency develops. To prevent permanent neurological damage, parenteral Vitamin B12 therapy must be considered even in the absence of Vitamin B12 deficiency, especially in those patients already experiencing neurological symptoms.

Paradoxical association between dyspepsia and autoimmune chronic atrophic gastritis: Insights into mechanisms, pathophysiology, and treatment options

BACKGROUND

Autoimmune gastritis (AIG) is a progressive, chronic, immune-mediated inflammatory disease characterized by the destruction of gastric parietal cells leading to hypo/anacidity and loss of intrinsic factor. Gastrointestinal symptoms such as dyspepsia and early satiety are very common, being second in terms of frequency only to anemia, which is the most typical feature of AIG.

AIM

To address both well-established and more innovative information and knowledge about this challenging disorder.

METHODS

An extensive bibliographical search was performed in PubMed to identify guidelines and primary literature (retrospective and prospective studies, systematic reviews, case series) published in the last 10 years.

RESULTS

A total of 125 records were reviewed and 80 were defined as fulfilling the criteria.

CONCLUSION

AIG can cause a range of clinical manifestations, including dyspepsia. The pathophysiology of dyspepsia in AIG is complex and involves changes in acid secretion, gastric motility, hormone signaling, and gut microbiota, among other factors. Managing dyspeptic symptoms of AIG is challenging and there are no specific therapies targeting dyspepsia in AIG. While proton pump inhibitors are commonly used to treat dyspepsia and gastroesophageal reflux disease, they may not be appropriate for AIG. Prokinetic agents, antidepressant drugs, and non-pharmacological treatments may be of help, even if not adequately evidence-based supported. A multidisciplinary approach for the management of dyspepsia in AIG is recommended, and further research is needed to develop and validate more effective therapies for dyspepsia.

Diagnostic criteria and endoscopic and histological findings of autoimmune gastritis in Japan

The Japanese diagnostic criteria for autoimmune gastritis (AIG) were established by the "Study Group on the establishment of diagnostic criteria for type A gastritis," which is related to a workshop associated with the Japan Gastroenterological Endoscopy Society (JGES) and the Committee of AIG Research Group (CARP). The criteria were set as follows: the cases of confirmed diagnosis are patients in whom either the endoscopic or histological findings, or both, meet the requirements for AIG and who are confirmed to be positive for gastric autoantibodies (either anti-parietal cell or anti-intrinsic factor antibodies, or both). The presentation of endoscopic findings of early-stage AIG in the diagnostic criteria was withheld owing to the need for further accumulation and characterization of endoscopic clinical data. Therefore, diagnosis of early-stage AIG only requires histological confirmation and gastric autoantibody positivity. Suspected cases are patients in whom either the endoscopic or histological findings, or both, meet only the requirements for AIG. Histological findings only meet the requirements for early stage. AIG has been underdiagnosed in the past, but our study group's newly proposed diagnostic criteria will enable a more accurate and early diagnosis of AIG. The criteria can be used to stratify patients into various high-risk groups for gastric tumors and pernicious anemia. They would allow the establishment of an appropriate surveillance system in the coming years. Nevertheless, issues such as establishing the endoscopic findings of early-stage AIG and obtaining Japanese insurance coverage for gastric autoantibody tests require attention.

A Case of Autoimmune Gastritis and Hepatitis with Enlarging Gastric Polyps after Reducing the Dose of Prednisolone

Autoimmune gastritis is immune-mediated gastritis that destroys the oxyntic mucosa. Autoimmune hepatitis is an inflammatory liver disease caused by an autoimmune reaction. These diseases share similar pathogeneses as organ-specific autoimmune disorders; however, cases involving both diseases are quite rare and scarcely reported. Herein, we report a patient with concurrent autoimmune gastritis and hepatitis who developed enlargement of hyperplastic polyps and progression of gastric atrophy. The patient was a 79-year-old female referred to our hospital for the treatment of hyperplastic polyps detected on a follow-up upper gastrointestinal endoscopy. The patient's previous upper gastrointestinal endoscopy from 3 years prior revealed small hyperplastic polyps and no mucosal atrophy. However, the current upper gastrointestinal endoscopy revealed three 10-mm red polyps, severe mucosal atrophy in the corpus, and mild atrophy in the antral area. In addition, biopsy samples from the gastric body revealed decreased parietal cells and diffuse lymphocytic infiltration of the deep mucosa. Further, chromogranin A-positive endocrine cell micronests and enterochromaffin-like cell hyperplasia were detected. After confirming the diagnosis of autoimmune gastritis, endoscopic mucosal resection was performed for all the polyps, which were histopathologically diagnosed as hyperplastic polyps without malignancy. Therefore, clinicians should consider autoimmune gastritis for enlarged hyperplastic polyps and gastric atrophy progression.

Gastric adenocarcinoma of fundic gland type with autoimmune gastritis

An 87-year-old man with dysphagia presented to our hospital. He was diagnosed with autoimmune gastritis (AIG) with severe atrophy and hypergastrinemia. The patient was positive for parietal cell antibody (PCA) and anti-intrinsic factor antibody (IFA), without evidence of H. pylori infection. A flat elevated tumor was detected in the middle corpus, and therapeutic endoscopic submucosal dissection was performed. Histopathological examination revealed atypical cells mimicking the fundic glands, which were positive for pepsinogen-I and partially positive for MUC6 and H + /K + -ATPase, proliferating to the deep layer. The final diagnosis was gastric adenocarcinoma of the fundic gland type (GAFG). AIG is expected to be difficult to develop GAFG because the basal gastric glands are highly atrophic due to the production of PCA. However, some chief cells may remain and could have the potential to develop into malignancy during AIG progression. Therefore, careful observation is required in patients with AIG when considering the occurrence of GAFG.

Regression of Autoimmune Gastritis after Eradication of Helicobacter pylori

We report a case of autoimmune gastritis (AIG) in which gastric mucosal atrophy improved with Helicobacter pylori eradication. Based on endoscopic findings (advanced gastric atrophy with vascular visibility and diffuse redness in remnant oxyntic mucosa), a woman in her 40s was suspected of having AIG coexisting with an active H. pylori infection. This was confirmed by a positive anti-parietal cell antibody (PCA, 1:160), an elevated serum gastrin level (638 pg/mL), and positive anti-H. pylori antibody (Hp Ab, 15.5 U/mL) and H. pylori stool antigen tests. Seven months after eradication, reduced vascular visibility and disappearance of diffuse redness on endoscopy and reduced PCA (1:40) and Hp Ab (5.1 U/mL) titers were observed, although histopathological findings (basal-predominant lymphocytic infiltration, destruction of parietal and chief cells, pseudopyloric metaplasia, and enterochromaffin-like cell hyperplasia) were consistent with AIG. Endoscopy 26 months after eradication showed further improvement in atrophic findings in the gastric corpus and histopathological recovery of parietal and chief cells in fundic glands. Serum gastrin levels returned to normal (64 pg/mL), and the PCA titer fell further (1:20).

Autoimmune atrophic gastritis and coeliac disease: A case-control study

BACKGROUND

Autoimmune atrophic gastritis (AAG) is rarely associated with coeliac disease (CD).

AIMS

To assess the frequency of AAG-CD association and to compare clinical, biochemical, and histological features of adults affected by both diseases (cases) with AAG controls.

METHODS

This case-control study included 9 cases (F55%, median age 47, range 23-59yrs) matched (1:3) by age (±4 yrs) and gender to 27 controls randomly selected from our AAG cohort (2009-2021). The AAG and CD diagnosis was based on internationally agreed criteria.

RESULTS

Of 434 AAG patients (median age:62.5yrs, range18-92yrs, F:M ratio=2.2:1),9 had a concomitant diagnosis of CD. The occurrence of AAG-CD association was 2% and 1.65% among AAG/CD cohorts, respectively. Cases were significantly younger than AAG cohort (n = 425, p = 0.002). In 4/9cases, AAG was diagnosed by proactive screening for autoimmune disorders. Autoimmune thyroid disorders were present in 5/9 cases. Cases had a significant higher prevalence of normocytic anaemia than controls (p = 0.004). No significant differences were found between cases and controls concerning clinical and histological features.

CONCLUSIONS

AAG-CD association is rare. Gastric and duodenal biopsies might be advisable in young people with normocytic anaemia and associated autoimmune disorders to timely diagnose clinically silent conditions.

Pathophysiology and therapeutic management of anemia in gastrointestinal disorders

INTRODUCTION

Anemia is a common complication of gastrointestinal (GI) disorders, with a prevalence up to 60% in celiac disease (CeD) and inflammatory bowel disease (IBD). Iron deficiency anemia (IDA) is the most prevalent form of anemia in these conditions, but chronic inflammation and vitamin B12 deficiency represent other common contributing mechanisms, especially in IBD.

AREAS COVERED

We discuss the pathogenesis of anemia in various medical GI disorders, the sometime problematic distinction between IDA, anemia of inflammation (AI) and the association of the two, and therapeutic and preventive measures that can be useful for the management of anemia in GI disorders. Unfortunately, with the exception of IDA and AI in IBD, large RCT concerning the treatment of anemia in GI disorders are lacking.

EXPERT OPINION

Anemia management strategies in GI disorders are outlined, with a focus on the main prevention, diagnostic, and therapeutic measures. Specific problems and situations such as the role of gluten-free diet for IDA treatment in CeD, the choice between oral and parenteral supplementation of iron or vitamin B12 in carential anemias, the use of endoscopic procedures to stop bleeding in intestinal angiodysplasia and preventive/treatment strategies for NSAID-associated GI bleeding are discussed.

Time course and risk factors of evolution from potential to overt autoimmune gastritis

BACKGROUND

The natural history of patients with potential autoimmune gastritis (AIG), defined by the presence of serum anti-parietal cell antibody (PCA) positivity and no gastric histopathological alterations, is unknown. We therefore aimed to assess the natural history and clinical correlates of potential autoimmune gastritis (AIG).

METHODS

In 2000-2019, we enrolled potential AIG patients by monitoring once a year (±6 months) histopathological evolution into overt AIG, defined as the occurrence of atrophy in the oxyntic mucosa. Factors affecting disease progression were assessed.

RESULTS

Fifty-one potential AIG patients (median age 57 years, IQR 43-73, F:M ratio 1.7:1) were monitored for up to 15 years (median 6 years, IQR 3-8). Of them, 24 (47.1%) evolved into overt AIG in a median time of 2 years (IQR 2-4.5). Having a concomitant autoimmune disorder (HR 4.09, 95% CI 1.52-11.00; p = 0.005), but not older age (HR 1.00, 95% CI 0.45-2.22; p = 0.992) and female sex (HR 1.19, 95% CI 0.51-2.78; p = 0.395), was associated with evolution into overt AIG.

CONCLUSIONS

Roughly one in two potential AIG patients will evolve into overt AIG over a median time of two years, especially those with a concurrent autoimmune disorder.

Endoscopic resection for early gastric cancer: Towards a global understanding

Gastric cancer is widespread globally, and disease diagnosis is accompanied by high mortality and morbidity rates. However, prognoses and survivability have improved following implementation of surveillance and screening programs, which have led to earlier diagnoses. Indeed, early diagnosis itself supports increased surgical curability, which is the main treatment goal and guides therapeutic choice. The most recent Japanese guidelines for endoscopic submucosal dissection and endoscopic mucosal resection for early gastric cancer consider the degree of endoscopic curability in relation to the characteristics of the gastric lesions. In clinical practice, the management approach for both prevention and treatment should be similar to that of colon lesions; however, unlike the established practices for colorectal cancer, the diagnostic and therapeutic pathways are not shared nor widespread for gastric cancer. Ultimately, this negatively impacts the opportunity to perform an endoscopic resection with curative intent.

Early autoimmune gastritis presenting with a normal endoscopic appearance

This report describes a patient with early-stage autoimmune gastritis (AIG) presenting with a normal endoscopic appearance. A 66-year-old man with autoimmune thyroiditis was suspected of having AIG because of a previous history of vitamin B12 deficiency when receiving steroid therapy for interstitial pneumonia 5 years earlier. At presentation, he tested positive for anti-parietal cell antibody (1:320) and anti-intrinsic factor antibody, but not for vitamin B12 deficiency. His gastrin level was elevated (338 pg/mL), but his pepsinogen (PG) I level (56.1 ng/mL) and PGI/PGII ratio (7.6) were normal. Endoscopically, neither atrophic nor inflammatory changes were observed. Histopathologic examination, however, showed mild atrophic changes with dense lymphocytic infiltration in the deep lamina propria and focal destruction of parietal cells in the greater curvature of the corpus. PGI-positive/MUC6-positive pseudo-pyloric metaplasia was observed in the area from which H⁺/K⁺-ATPase-positive parietal cells had disappeared. Chromogranin A immunostaining showed linear hyperplasia of enterochromaffin-like cells. By contrast, atrophic changes were not evident in the lesser curvature of the corpus, except for mild lymphocytic infiltration around and into the fundic glands. These serological and histopathological findings suggested that the patient had early-stage AIG with a normal endoscopic appearance.

Autoimmune gastritis induces aberrant DNA methylation reflecting its carcinogenic potential

BACKGROUND

Autoimmune gastritis (AIG) is a chronic inflammatory condition in gastric mucosa and is associated with increased cancer risk, though not as high as that by Helicobacter pylori (H. pylori)-associated gastritis (HPG). Although aberrant DNA methylation is induced by HPG and the level correlates with the risk of gastric cancer, DNA methylation induction by AIG is unknown.

METHODS

Gastric mucosa samples from the corpus were collected from 12 people with AIG without H. pylori infection, 10 people with HPG, and eight healthy volunteers. Genome-wide DNA methylation analysis was conducted using Infinium Methylation EPIC array. Gene expression was analyzed by quantitative RT-PCR.

RESULTS

The AIG samples had extensive aberrant DNA methylation but presented unique methylation profiles against the HPG samples after correction of leucocyte fractions. Comparison between the AIG and HPG samples showed that AIG induced methylation, but less than HPG, in overall CpG sites and also in promoter CpG islands. Promoter CpG islands of tumor-suppressor genes in the pathway of cell cycle, cell adhesion, p53, and WNT were highly methylated in the AIG samples, but more so in the HPG samples. The expression levels of IL1B and IL8, secreted by macrophage, were significantly lower in the AIG samples than in the HPG samples, suggesting that a difference in inflammatory response affected the degree and patterns of aberrant DNA methylation.

CONCLUSIONS

AIG induced aberrant DNA methylation in gastric mucosa. However, the degree of DNA methylation was less than that by HPG, which reflected carcinogenic risk.

Decreased anti-parietal cell antibody titer in the advanced phase of autoimmune gastritis

BACKGROUND

Autoimmune gastritis (AIG) is histologically classified into three phases according to the severity of oxyntic mucosal atrophy: early, florid, and end phases. This study aimed to clarify the relationship between the AIG phase and the anti-parietal cell antibody titer.

METHODS

Patients who underwent upper gastrointestinal endoscopy were retrospectively reviewed in this study. We enrolled patients who were histologically diagnosed with AIG and serologically tested for anti-parietal cell antibody (APCA). AIG patients were classified into three groups: early, florid, and end phase groups. Clinical characteristics, including APCA titers, were compared among these three groups.

RESULTS

A total of 44 AIG patients were enrolled. There were two patients in the early phase, 11 in the florid phase, and 31 in the end phase. APCA-positive rates were 100% in the early phase, 90.9% in the florid phase, and 90.3% in the end phase. The mean APCA titer was 480 U in the early phase, 220 U in the florid phase, and 150 U in the end phase. There was a stepwise decrease in the APCA titer from the early phase to the end phase. The mean APCA titer for the end phase was significantly lower than that of the early phase or florid phase. Additionally, there was a stepwise decrease in serum gastrin levels from the early phase to the end phase.

CONCLUSION

AIG progresses from the early phase to the end phase, and the APCA titer shows a decrease. The negativity of APCA could occur, especially in the end phase.

Intrinsic factor autoantibodies by luminescent immuno-precipitation system in patients with corpus atrophic gastritis

Background

Corpus atrophic gastritis (CAG) may lead to intrinsic factor (IF) deficiency and vitamin B₁₂ malabsorption. Intrinsic factor autoantibodies (IFA) are considered markers of pernicious anemia, but their clinical utility in CAG has not been evaluated. This study aimed to assess IFA in CAG patients and controls using a luciferase immunoprecipitation system (LIPS).

Methods

Recombinant nanoluciferase-tagged IF secreted from transfected Expi293F cells was used as antigen in an IFA-LIPS assay. IFA IgG were measured in sera from subjects undergoing gastroscopy and biopsy (updated Sydney system) mainly for anemia (57%) or dyspepsia (34%). This cohort comprised 105 patients with histologically-proven-CAG (cases: median age 64 years, 68% females) and 110 subjects with suspected CAG that were histologically negative (controls: median age 67 years, 54% females). Cut-off values were selected by Q-Q-plot analysis (negative: <2.5 arbitrary units).

Results

IFA levels were higher in cases than in controls (Mann-Whitney:p < 10⁻⁵). The ROC-AUC was 0.67 (95%CI 0.60–0.73, p < 0.0001). The IFA LIPS sensitivity and specificity for CAG were 32% (95% CI 24–42) and 95% (95% CI 90–99). This diagnostic performance remained similar after stratification for the presence/absence of anemia, dyspepsia or vitamin B₁₂ deficiency. IFA levels were higher in females compared with males (p = 0.0127). In females aged <65 years, IFA-positives were more prevalent than in males (43.5% vs 6.6%, p = 0.011).

Conclusions

The IFA-LIPS assay discriminated between CAG patients and controls showing a good specificity (95%) at the cost of sensitivity (32%). IFA-positivity occurred independently from anemia and vitamin B₁₂ deficiency, but was more frequent in younger females. IFA testing should be considered in patients at high clinical suspicion of CAG.

•

A novel diagnostic autoantibody test for intrinsic factor autoantibodies using a LIPS in histologically-proven CAG patients and controls.

•

This assay discriminated between patients and controls with a good specificity and a relatively low sensitivity that reflects the likely low prevalence of intrinsic factor antibodies in CAG.

•

Positivity occurred independently from anemia and vitamin B₁₂ deficiency.

•

Intrinsic factor antibodies should be assessed in patients at high clinical suspicion of CAG.

Pathological Diversity of Gastric Cancer from the Viewpoint of Background Condition

BACKGROUND

The prevalence of Helicobacter pylori infection and chronic atrophic gastritis is decreasing in Japan, which has led to a decline in the incidence of gastric cancer. However, there are various subtypes of gastric cancer that arise from the background mucosa without H. pylori infection, and their histological characteristics are distinct from those of gastric cancer with chronic atrophic gastritis.

SUMMARY

In this review, after a brief overview of conventional gastric carcinoma with H. pylori infection, including its molecular classification, histological characteristics of gastric cancer after eradicating H. pylori are described. The clinicopathological characteristics of gastric cancer independent of H. pylori infection are then explained. Autoimmune gastritis (type A gastritis) increases the risk of gastric adenocarcinoma and neuroendocrine tumors. Gastric carcinoma without H. pylori infection has various histological subtypes, including fundic gland-type adenocarcinoma (oxyntic gland adenoma), foveolar-type adenocarcinoma/adenoma, signet ring cell carcinoma, and adenocarcinoma of the esophagogastric junction. In addition, some familial gastric cancer syndromes, including hereditary diffuse gastric cancer, familial adenomatous polyposis, and gastric adenocarcinoma and proximal polyposis of the stomach, are also discussed. Key Messages: Although the incidence of gastric cancer will decrease in the near future, the diversity of gastric cancer pathology will be enhanced because H. pylori-negative gastric cancer will have a significant impact on the clinical practice guidelines for gastric cancer. Gastroenterologists and pathologists should be aware of the morphological diversity of H. pylori-negative gastric cancer, and attention should be paid to the status of the background gastric mucosa while examining gastric cancer.

Pathogenic ATM Variant-Harbouring Well-Differentiated Aggressive Type 1 Gastric Neuroendocrine Tumour with High-grade Features (G3 NET): a New Addition to the Clinical and Pathological Spectrum of Gastric Neuroendocrine Neoplasms

Gastric type 1 neuroendocrine tumours are considered to have low rates of proliferation and a good prognosis. We report here a patient with an aggressive well-differentiated high-grade gastric neuroendocrine tumour (gastric grade 3 NET), in a context of autoimmune gastritis. Consistent with grade 3 disease, the tumour had a Ki-67 proliferation index of 30%. Targeted next-generation sequencing identified variants of four genes, including a pathogenic ATM variant underlying the differentiation and metastatic potential of the tumour. Liver metastasis was diagnosed during follow-up, and the patient died after 6 years, due to disease progression.

Clue of Diagnosis for Autoimmune Gastritis

BACKGROUND

The diagnostic clues for autoimmune gastritis (AIG) can be classified into 2 categories: endoscopic findings and pathological diagnosis. We believe that research on the AIG detection rate by endoscopists could provide a better understanding of the diagnosis of AIG. This study aimed to clarify the ratio of the endoscopic and the pathological diagnoses of AIG.

METHODS

We retrospectively reviewed consecutive patients who underwent esophagogastroduodenoscopy (EGD). During their first EGD, the gastric mucosa with C2 atrophy or more was biopsied for pathological evaluation based on the updated Sydney system. A gastric biopsy was also performed after Helicobacter pylori eradication, obtaining specimens from at least 2 sites, the greater curvature of the corpus and the antrum. We enrolled patients who were positive for the anti-parietal cell antibody and were diagnosed with AIG, histologically and/or endoscopically. The detection rates of AIG were compared between endoscopic diagnosis and pathological diagnosis.

RESULTS

A total of 10,822 patients underwent EGD during the study period. Finally, 41 patients with AIG were enrolled, leading to an AIG prevalence of 0.38% in this study. As for the clue leading to AIG detection, 31.7% (13/41) were diagnosed through endoscopy (proximal-predominant atrophy), and 68.3% (28/41) were diagnosed pathologically. The AIG detection rate by endoscopists in the posteradication group was significantly lower than in the H. pylori-negative group (p < 0.05).

CONCLUSION

Endoscopists frequently overlooked AIG, especially in posteradication cases. Pathological assessment using the updated Sydney system after H. pylori eradication might be a promising strategy to detect AIG better.

Lack of uniformity in reporting autoimmune gastritis among a diverse group of pathologists

Autoimmune gastritis (AIG) is a clinicopathologic diagnosis requiring characteristic histopathology and correlation with laboratory work-up. To better understand how the diagnosis of AIG is made and reported in the pathology community, we conducted an anonymous web-based survey which was circulated among a diverse group of pathologists. Excluding trainees there were 64 respondents: 25 academic gastrointestinal pathologists (AGI, 39%), 22 academic general pathologists (AGP, 34%), 17 private general pathologists (PP, 27%). Our survey results highlighted variations in work-up and sign-out practices. The type of metaplasia needed to diagnose AIG lacked consensus. There was variation in accurate interpretation of immunostains with a trend towards more accurate diagnosis of enterochromaffin-like (ECL) cell hyperplasia by AGI (92%) and AGP (95%) than PP (71%) (p = 0.07). G-cells in antrum on neuroendocrine immunostain, a mimicker of ECL cell hyperplasia, was more frequently misdiagnosed by PP/ AGP (44%), versus AGI (12%) (p = 0.02). A triple immunostain panel (H. pylori, neuroendocrine, gastrin) was used in the work-up of AIG by 72% of AGI versus 23% AGP and 12% PP (p = 0.000061). The less-specific term "atrophic gastritis" was used in the diagnostic line more by respondents with >10 years sign-out experience compared with others (p = 0.04). In conclusion, the survey results highlighted deficiencies in the interpretation of neuroendocrine immunostains which is crucial for AIG diagnosis, as well as variation in reporting practices and definitions. Uniform criteria and terminology are needed in this field to improve communication with clinicians, resulting in appropriate testing and follow-up.

Gastritis: The clinico-pathological spectrum

The inflammatory spectrum of gastric diseases includes different clinico-pathological entities, the etiology of which was recently established in the international Kyoto classification. A diagnosis of gastritis combines the information resulting form the gross examination (endoscopy) and histology (microscopy). It is important to consider the anatomical/functional heterogeneity of the gastric mucosa when obtaining representative mucosal biopsy samples. Gastritis includes self-limiting and non-self-limiting (long-standing) inflammatory diseases, and the latter are epidemiologically, biologically and clinically linked to the onset of gastric cancer (i.e. "inflammation-associated cancer"). Different biological models of inflammation-associated gastric oncogenesis have been proposed. Helicobacter pylori (H. pylori) gastritis is the most prevalent worldwide, and H. pylori is classified as a first-class carcinogen. On these bases, eradicating H. pylori is mandatory for the primary prevention of gastric cancer. Non-self-limiting gastritis may also be triggered by the immune-mediated destruction of gastric parietal cells, resulting in autoimmune gastritis. In both H. pylori-related and autoimmune gastritis, the non-self-limiting inflammation results in atrophy of the gastric mucosa, which is the main factor promoting gastric cancer. Long-term follow-up studies consistently demonstrate the prognostic impact of the histological staging of gastritis in gastric cancer secondary prevention strategies.

Collagenous gastritis: Epidemiology and clinical associations

BACKGROUND

the rare occurrence of collagenous gastritis (CG) makes its epidemiology difficult to investigate. We designed a study to determine the demographic and clinical characteristics as well as the associations of CG with other upper gastrointestinal diseases in a large national clinicopathological database.

METHODS

from the IDEA database we extracted all patients with histopathologically documented CG and, in a case-control study, we compared 168 subjects with and 1,286,165 subjects without CG using odds ratios (OR) with their 95% confidence intervals (CI).

RESULTS

the prevalence of CG was 13 per 100,000 EGDs. CG was significantly more common among female than male patients (OR: 1.69, 95% CI: 1.20-2.39) and was characterized by a bi-modal age distribution (first peak in patients aged 10-19, second peak primarily in females aged >60 years). CG patients presented with diarrhea (18%), anemia (12%), weight loss (11%), and vomiting (10%). CG was significantly associated with other lymphocytic disorders of the upper gastrointestinal tract, including celiac sprue (2.12, 1.55-2.88), duodenal intraepithelial lymphocytosis (3.71, 2.30-5.98), and lymphocytic gastritis (23.2, 10.9-49.5). CG persisted in 69% of patients who underwent multiple consecutive endoscopies.

CONCLUSIONS

the epidemiologic features of collagenous gastritis reflect on different etiologies contributing to its occurrence in children and adults.

Pediatric autoimmune gastritis: clinical correlates and histologic features

Autoimmune gastritis is a well-known pathologic entity, but there are few studies that examine its clinical and histologic presentation in children. This is a single institution, retrospective study performed on patients diagnosed from 2011 through 2019. Patients were identified by their pathologic diagnosis within the laboratory information system. The electronic medical record and archived slides were reviewed. Twenty-two children (3 months to 18 years; median, 10.9 years) with autoimmune gastritis were diagnosed of a total of 14,257 nonconsultation gastric biopsies from unique patients (0.15% prevalence). Patients with autoimmune gastritis were diagnosed at an average age of 10.9 years and were mostly female (68.2% women, 31.8% men). The majority had extragastric immune disorders (13/22; 59.1%). All patients in the study had gastric body mucosa with enterochromaffin-like cell hyperplasia, atrophy, and histologic features of chronic injury. Most biopsies showed gastric body metaplasia (n = 19) or active gastric inflammation. However, antral atrophy was also observed in 12 patients, and antral metaplasia was identified in one patient; four patients had active chronic antral gastritis. All biopsies were negative for Helicobacter pylori. Pediatric autoimmune gastritis is a rare disorder that should be recognized because of its systemic effects with long-term morbidity. In addition, the possibility of tandem extragastric immune disorders should be considered when a diagnosis of pediatric autoimmune gastritis is established.

Endoscopic surveillance at 3 years after diagnosis, according to European guidelines, seems safe in patients with atrophic gastritis in a low-risk region

BACKGROUND

Autoimmune and multifocal atrophic gastritis (AG) are at risk for gastric neoplastic lesions. European guidelines recommend surveillance with high-quality endoscopy every 3 years.

AIM

To prospectively investigate the occurrence of gastric neoplastic lesions at the 3-year follow-up in patients with autoimmune and multifocal AG.

METHODS

Longitudinal cohort study conducted between 2011 and 2019: consecutive patients with histological diagnosis of autoimmune or multifocal AG underwent follow-up gastroscopy 3 years after diagnosis with high-resolution-narrow-band-imaging endoscopes.

RESULTS

Overall, 160 patients were included(F117(73.0%);median age 66(35-87)years). Autoimmune and multifocal AG were present in 122(76.3%) and 38(23.7%) patients, respectively. At the 3-year follow-up, 16(10.0%) patients presented 16 gastric neoplastic lesions: 3(18.7%) gastric cancers, 4(25.0%) low-grade dysplasia, 2(12.5%) low-grade dysplasia adenomas, 7(43.7%) type-1 neuroendocrine tumours. In these patients, OLGA and OLGIM III/IV stages were present in 4(25.0)% and 1(6.3%), respectively; 11(69.0%) presented autoimmune AG, and all but one(93.7%) had parietal cells antibodies positivity (p = 0.026 vs patients without lesions). All lesions were endoscopically(87.5%) or surgically(12.5%) treated with favourable outcome. Age>70 years was associated with a 9-fold higher probability of developing gastric epithelial neoplastic lesions (OR 9.6,95CI% 1.2-79.4,p = 0.0359).

CONCLUSIONS

The first endoscopic surveillance 3 years after diagnosis seems safe for autoimmune and multifocal AG patients and should be offered to elderly patients who are at higher risk for gastric neoplasia.

A case of early autoimmune gastritis with characteristic endoscopic findings

Significant atrophic gastritis in the fundic gland region is a well-known endoscopic finding observed in autoimmune gastritis (AIG). The endoscopic features of early AIG have not been reported. Iron deficiency, vitamin B₁₂ deficiency, anemia, or neurological symptoms may not be observed in the early stages of AIG, and it may thus be difficult to diagnose early AIG based on clinical findings. We treated a 50-year-old Japanese female whose condition was suspected to be early AIG. The endoscopic findings showed normal gastric pyloric gland mucosa, and diffuse reddened and edematous gastric fundic gland mucosa. Pathologically, local infiltration of lymphocytes and decrease of parietal cells was present in a deep part of the gastric fundic gland mucosa. Blood tests showed that the titer of parietal cell antibody (PCA) was 1:320 and the gastrin level was 820 pg/ml. We determined that the patient had AIG because she also had Hashimoto’s disease, the PCA titer was high, the serum gastrin level was slightly increased, and inflammation was observed only in the gastric body on the endoscopic images. To the best of our knowledge, this is the first case report of endoscopic findings that suggest early AIG, before atrophic changes were observed.

Pyloric, pseudopyloric, and spasmolytic polypeptide-expressing metaplasias in autoimmune gastritis: a case series of 22 Japanese patients

There are two types of pyloric gland-like metaplasia in the corpus of stomach: pyloric and pseudopyloric metaplasias. They show the same morphology as the original pyloric glands in H&E staining. Pseudopyloric metaplasia is positive for pepsinogen (PG) I immunohistochemically, whereas pyloric metaplasia is negative. Recently, spasmolytic polypeptide-expressing metaplasia (SPEM) is proposed for pyloric gland-like metaplasia mainly in animal experiments. SPEM expresses trefoil factor family 2 (TFF2) and is often considered synonymous with pseudopyloric metaplasia. We reviewed consecutive 22 Japanese patients with autoimmune gastritis (AIG) to investigate TFF2 expression in pyloric and pseudopyloric metaplasias by counting all pyloric gland-like glands in biopsy specimens taken from greater curvature of the middle corpus according to the Updated Sydney System. Pyloric metaplasia was seen in all the 22 cases, and pseudopyloric metaplasia was found in 15 cases. Of 1567 pyloric gland-like glands in all the cases, 1381 (88.1%) glands were pyloric metaplasia glands, and the remaining 186 (11.9%) glands were pseudopyloric metaplasia glands. TFF2 expression was observed in pyloric or pseudopyloric metaplasia glands in 20 cases. TFF2 expression was recognized in 409 of 1381 (26.9%) pyloric metaplasia glands and 27 of 186 (14.5%) pseudopyloric metaplasia glands (P<0.01, chi-square test). In conclusion, SPEM was not always the same as pseudopyloric metaplasia in human AIG, and the majority of metaplasia in AIG was not pseudopyloric but pyloric metaplasia.

A case of eosinophilic esophagitis with autoimmune polyendocrine syndrome type 2, including autoimmune gastritis

Both eosinophilic esophagitis (EoE) and autoimmune polyendocrine syndrome (APS) are relatively rare diseases in Japan. We herein report a case of EoE with APS in a 67-year-old Japanese man who presented with chest pain and dysphagia. On the basis of endoscopic findings and histological analysis, we diagnosed the patient with EoE along with autoimmune gastritis. Additional serological examinations revealed the presence of Hashimoto's thyroiditis and type 1 diabetes, which led to the final diagnosis of APS. His symptoms did not respond to treatment with a proton-pump inhibitor but improved with topical steroid therapy. This case of coexisting EoE and APS-2 is quite rare and has several implications for the pathogenesis of both conditions.

Histological assessment of gastric pseudopyloric metaplasia: Intra- and inter-observer consistency

BACKGROUND

The histological spectrum of oxyntic mucosal atrophy (a major determinant of gastric cancer risk) includes pseudopyloric metaplasia (PPM), which histological assessment has been regarded as unreliable. PPM consistently expresses Trefoil-Factor 2 (TFF2), which is histochemically detecteble (TFF2-IHC).

AIMS

Intra- and inter-observer consistency in assessing PPM was examined using both hematoxylin & eosin (H&E) and TFF2-IHC.

MATERIALS AND METHODS

Seventy-four oxyntic biopsy samples obtained from autoimmune gastritis were considered. Two serial histological sections obtained from the paraffin-embedded tissue-samples were stained with H&E and TFF2-IHC. Three pathologists (Alpha, Beta, Gamma) independently scored PPM by both staining and the Intra- and inter-observer consistency (H&E versus TFF2-IHC) was calculated using k-statistics and/or Spearman's coefficient.

RESULTS

Based on H&E-stain versus TFF2-IHC, intra-observer consistency in PPM assessement was ranked as consistently "good" (k-values: Alpha=0.79; Beta=0.78; Gamma=0.75). Based on H&E, the overall PPM inter-observer consistency among the 3 observers was ranked as "good" (k=0.77) (the inter-observer consistency for pairs of observers was as follows: Alpha versus Beta k=0.88; Alpha versus Gamma k=0.87; Beta versus Gamma k=0.80). Based on TFF2-IHC, the overall PPM inter-observer agreement was ranked as "excellent" (k=0.91) (the inter-observer consistency for pairs of observers was as follows: Alpha versus Beta k=1; Alpha versus Gamma k=0.91; Beta versus Gamma k=0.91).

CONCLUSION

Relying on either H&E staining or TFF2-IHC, pathologists assess PPM consistently.

Histological Features of Gastric Mucosa Serologically Diagnosed as Gastric Atrophy without Helicobacter pylori Infection

BACKGROUND/AIMS

Although gastric atrophy is primarily caused by Helicobacter pylori infection, it is unclear why patients serologically diagnosed with gastric atrophy without H. pylori infection exhibit greater atrophy. We investigated histopathological features in serologically diagnosed gastric atrophy without H. pylori infection.

METHODS

Thirty-four patients with positive serum pepsinogen and negative serum H. pylori antibody tests underwent gastric biopsy and histological evaluation. The presence of enterochromaffin-like cells (ECL) was also evaluated. Gastric cancer risks for each histological feature according to the Operative Link on Gastritis Assessment (OLGA) and Operative Link on Gastric Intestinal Metaplasia (OLGIM) were assessed.

RESULTS

Twenty-five (74%) patients had histological gastric atrophy. Among those, the following histological subgroups were identified: eight had H. pylori but no ECL, 13 had neither H. pylori nor ECL, and 4 had ECL without H. pylori. Nine patients without histological atrophy had neither H. pylori nor ECL. Patients with H. pylori on histological diagnosis had significantly higher scores on OLGA and OLGIM.

CONCLUSIONS

Various histological features, with significant differences in gastric cancer risk, were identified in the gastric mucosa serologically diagnosed with atrophy without H. pylori infection. Therefore, serological screening for gastric cancer risk tests has several limitations, and additional evaluations should be considered.

A case of autoimmune gastritis with fundic gland polyp-like pseudopolyps presenting with nodular enterochromaffin-like cell hyperplasia

Pseudopolyps, a type of remnant oxyntic mucosa on a background of corpus-restricted mucosal atrophy, are a characteristic endoscopic finding in autoimmune gastritis (AIG). Linear or nodular enterochromaffin-like (ECL) cell hyperplasia, a characteristic histopathological finding of AIG, is not generally found in pseudopolyps. We report a case of AIG with fundic gland polyp (FGP)-like pseudopolyps containing nodular ECL cell hyperplasia. A 64-year-old man underwent esophagogastroduodenoscopy, which revealed atrophic changes limited to the corpus, with a normal antrum. The greater curvature was less atrophic than the lesser curvature. Sessile or semipedunculated polypoid lesions were observed on the greater curvature and on the anterior and posterior walls of the corpus. The polypoid lesions resembled FGPs, although some were larger than FGPs generally are. Histologically, non-atrophic fundic glands with parietal cell pseudohypertrophy were observed in the upper regions of the polypoid lesions. By contrast, at the base of the lesions, where linear and nodular ECL cell hyperplasia was identified by immunohistochemical staining, destruction of fundic glands with lymphocytic infiltration, loss of parietal cells, and pseudopyloric metaplasia was observed. Anti-parietal cell antibody positivity and hypergastrinemia confirmed the diagnosis of AIG with pseudopolyps. FGP-like pseudopolyps can, therefore, be present with nodular ECL cell hyperplasia in AIG.

Helicobacter pylori-induced inflammation masks the underlying presence of low-grade dysplasia on gastric lesions

BACKGROUND

Helicobacter pylori (H. pylori) infection has been associated with a long-term risk of precancerous gastric conditions (PGC) even after H. pylori eradication.

AIM

To investigate the efficacy of High-Resolution White-Light Endoscopy with Narrow-Band Imaging in detecting PGC, before/after H. pylori eradication.

METHODS

We studied 85 consecutive patients with H. pylori-related gastritis with/without PGC before and 6 mo after proven H. pylori eradication. Kimura-Takemoto modified and endoscopic grading of gastric intestinal metaplasia classifications, were applied to assess the endoscopic extension of atrophy and intestinal metaplasia. The histological result was considered to be the gold standard. The Sydney System, the Operative-Link on Gastritis-Assessment, and the Operative-Link on Gastric-Intestinal Metaplasia were used for defining histological gastritis, atrophy and intestinal metaplasia, whereas dysplasia was graded according to World Health Organization classification. Serum anti-parietal cell antibody and anti-intrinsic factor were measured when autoimmune atrophic gastritis was suspected.

RESULTS

After H. pylori eradication histological signs of mononuclear/polymorphonuclear cell infiltration and Mucosal Associated Lymphoid Tissue-hyperplasia, disappeared or decreased in 100% and 96.5% of patients respectively, whereas the Operative-Link on Gastritis-Assessment and Operative-Link on Gastric-Intestinal Metaplasia stages did not change. Low-Grade Dysplasia prevalence was similar on random biopsies before and after H. pylori eradication (17.6% vs 10.6%, P = 0.19), but increased in patients with visible lesions (0% vs 22.4%, P < 0.0001). At a multivariate analysis, the probability for detecting dysplasia after resolution of H. pylori-related active inflammation was higher in patients with regression or reduction of Mucosal Associated Lymphoid Tissue hyperplasia, greater alcohol consumption, and anti-parietal cell antibody and/or anti-intrinsic factor positivity [odds ratio (OR) = 3.88, 95% confidence interval (CI): 1.31-11.49, P = 0.01; OR = 3.10, 95%CI: 1.05-9.12, P = 0.04 and OR = 5.47, 95%CI: 1.33-22.39, P < 0.04, respectively].

CONCLUSION

High-Resolution White-Light Endoscopy with Narrow-Band Imaging allows an accurate diagnosis of Low-Grade Dysplasia on visible lesions after regression of H. pylori-induced chronic gastritis. Patients with an overlap between autoimmune/H. pylori-induced gastritis may require more extensive gastric mapping.

Serum chromogranin A level continuously rises with the progression of type 1 diabetes, and indicates the presence of both enterochromaffin-like cell hyperplasia and autoimmune gastritis

AIMS/INTRODUCTION

The relationship of chromogranin A (CgA) levels above the normal range with various outcomes, such as glycated hemoglobin levels, enterochromaffin-like cell hyperplasia and autoimmune gastritis, was investigated in type 1 diabetes patients with special regard to the progression of comorbidities.

MATERIALS AND METHODS

A cohort study on 153 type 1 diabetes patients was carried out with a prospective branch on clinical and laboratory data, and a retrospective branch on histological data obtained by gastroscopy.

RESULTS

Patients with CgA levels above the upper limit of the normal range (n = 28) had significantly higher glycated hemoglobin levels (P = 0.0160) than those with CgA in the normal range (n = 125). The correlation between CgA and glycated hemoglobin was significant (P < 0.0001), but weak (R = +0.32). A slight, but steady elevation (P = 0.0410) in CgA level was observed to co-vary with the duration of type 1 diabetes. Enterochromaffin-like cell hyperplasia and autoimmune gastritis was significantly more frequent (P = 0.0087 for both) in the high CgA group. Detailed analyses on gastric tissue samples confirmed a progression of enterochromaffin-like cell hyperplasia (P = 0.0192) accompanied by CgA elevation (P = 0.0316).

CONCLUSIONS

The early detection and follow up of the later progression of enterochromaffin-like cell hyperplasia and autoimmune gastritis into gastric neuroendocrine tumors, which have ~100-fold greater incidence in type 1 diabetes patients, can be achieved by assessment of CgA levels. Therefore, the use of CgA could be considered as a novel auxiliary biomarker in the care of these type 1 diabetes complications.

Case Report: Simultaneously diagnosed gastric adenocarcinoma and pernicious anemia - a classic association

Primary gastric cancer remains one of the most prevalent malignancies worldwide. Often patients remain asymptomatic until it is detected at an advanced stage with a poor prognosis. Thus, it’s characteristically difficult to initially diagnose until it becomes late stage, at which point prognosis becomes poor. Pernicious anemia is a classic risk factor for the development of primary gastric cancer, but is uncommonly seen in clinical practice. Over time, patients who produce the autoantibodies to intrinsic factor that cause pernicious anemia typically will present initially with clinically significant megaloblastic anemia and peripheral neuropathy. However, patients can also present with more nonspecific signs and symptoms. Thus, clinicians should remain vigilant as circulating anti-intrinsic factor antibodies only worsen the disease over time and increase the risk of developing primary gastric cancer. This report not only presents the rare concurrent diagnosis of pernicious anemia and gastric cancer, but also aims to increase clinical awareness of these two conditions’ classic association because early diagnosis and treatment significantly impacts morbidity and mortality.

Thiol/disulfide homeostasis and ischemia modified albumin levels in autoimmune gastritis and their relations with gastric emptying

Background/aim

Autoimmune gastritis is an autoimmune and inflammatory disorder. The aim of this study is to examine dynamic thiol/disulfide homeostasis and ischemia modified albumin levels, and to analyze the association between thiol/disulfide homeostasis and gastric emptying time in autoimmune gastritis.

Materials and methods

Thiol/disulfide homeostasis tests and ischemia modified albumin levels were determined in 50 autoimmune gastritis patients and 53 healthy subjects. Patients with delayed and normal gastric emptying were compared by thiol/disulfide homeostasis tests.

Results

The results showed that native thiol (μmol/L), total thiol (μmol/L), and native thiol/total thiol ratio (%) of the patients with autoimmune gastritis decreased compared to the control group (177.7 ± 34.18 vs. 245.25 ± 33.83, P = 0.001, 227.25 ± 36.78 vs. 284.20 ± 27.19, P = 0.03, and 8.84 ± 1.1 vs. 7.74% ± 1.3%, P = 0.001). In addition, native thiol (μmol/L), total thiol (μmol/L), and native thiol/ total thiol ratio (%) were found to be lower in patients with delayed gastric emptying (198.65 ± 24.27 vs. 167.12 ± 20.51, 241.81 ± 27.14 vs. 213.92 ± 26.35, 8.34 ± 1.29 vs. 7.20 ± 1.83, P = 0.001). Disulfide level, disulfide/native thiol, disulfide/total thiol (P = 0.001) ratios, and ischemia modified albumin levels (ABSU, 0.71 ± 0.08 vs. 0.83 ± 0.07) were found to be higher in autoimmune gastritis patients with delayed gastric emptying (P = 0.001).

Conclusion

The results showed that thiol/disulfide homeostasis in patients with autoimmune gastritis caused an increase in ischemia modified albumin and disulfide whereas a decrease in thiols. An altered thiol/disulfide balance was also observed in patients with delayed gastric emptying. These results suggest that the oxidative process is involved in patients with autoimmune gastritis.

Anti-gastric parietal cell antibodies for autoimmune gastritis screening in juvenile autoimmune thyroid disease

OBJECTIVE

Patients with autoimmune thyroid disease (ATD) have a higher prevalence of autoimmune gastritis (AIG) compared with the general population. The association between ATD and AIG is poorly characterized in the pediatric age. We reviewed the prevalence of anti-gastric parietal cell antibodies (PCA) in young patients with ATD to evaluate its usefulness as a marker for AIG screening.

METHODS

We evaluated 220 children and adolescents (11.28 ± 6.37 years) with ATD (186 with autoimmune thyroiditis (AT) and 34 with Graves' disease (GD). At ATD diagnosis and annually thereafter, blood counts and PCA levels were measured. In patients positive for PCA, plasma gastrin, chromogranin A, vitamin B₁₂, iron and ferritin levels and H. pylori antigen were measured. PCA-positive patients > 18 years were invited to undergo a gastroscopic exam.

RESULTS

PCA positivity was detected in ten (4.5%) subjects (5F/5M; 12.6 ± 3.4 years). The prevalence of PCA positivity was not significantly different in the comparison of GD and AT patients (p = 0.9). PCA positivity was detected after 2.7 ± 2.7 years of follow-up in AT and 4.4 ± 4.0 years in GD (p = 0.4). Autoantibody positivity was more prevalent in female patients, in both AT and GD (p = 0.02 and p = 0.03, respectively). At detection of PCA positivity, five out of ten PCA-positive patients had iron deficiency, four vitamin B₁₂ deficiency, two anemia, three hypergastrinemia and two elevated chromogranin values. Two patients had H. pylori infection. Gastroscopy was performed in the five ATD patients and in all patients, AIG was confirmed.

CONCLUSION

In the juvenile population, ATD and AIG may also be associated. PCA screening is useful to detect subjects at risk for this condition. Due to the longer life expectancy of the pediatric population and considering the relatively high risk of malignant transformation, early surveillance monitoring is mandatory for children and adolescents with ATD.

Chronic atrophic gastritis: Natural history, diagnosis and therapeutic management. A position paper by the Italian Society of Hospital Gastroenterologists and Digestive Endoscopists [AIGO], the Italian Society of Digestive Endoscopy [SIED], the Italian Society of Gastroenterology [SIGE], and the Italian Society of Internal Medicine [SIMI]

Chronic atrophic gastritis (CAG) is an underdiagnosed condition characterised by translational features going beyond the strict field of gastroenterology as it may manifest itself by a variable spectrum of gastric and extra-gastric symptoms and signs. It is relatively common among older adults in different parts of the world, but large variations exist. Helicobacter pylori-related CAG [multifocal] and autoimmune CAG (corpus-restricted) are apparently two different diseases, but they display overlapping features. Patients with cobalamin and/or iron deficiency anaemia or autoimmune disorders, including autoimmune thyroiditis and type 1 diabetes mellitus, should be offered screening for CAG. Pepsinogens, gastrin-17, and anti-H. pylori antibodies serum assays seem to be reliable non-invasive screening tools for the presence of CAG, helpful to identify individuals to refer to gastroscopy with five standard gastric biopsies in order to obtain histological confirmation of diagnosis. Patients with CAG are at increased risk of developing gastric cancer, and they should be estimated with histological staging systems (OLGA or OLGIM). H. pylori eradication may be beneficial by modifying the natural history of atrophy, but not that of intestinal metaplasia. Patients with advanced stages of CAG (Stage III/IV OLGA or OLGIM) should undergo endoscopic surveillance every three years, those with autoimmune CAG every three-five years. In patients with CAG, a screening for autoimmune thyroid disease and micronutrient deficiencies, including iron and vitamin B₁₂, should be performed. The optimal treatment for dyspeptic symptoms in patients with CAG remains to be defined. Proton pump inhibitors are not indicated in hypochlorhydric CAG patients.

Measurement of Autoantibodies to Gastric H+,K+-ATPase (ATP4A/B) Using a Luciferase Immunoprecipitation System (LIPS)

The Luciferase Immuno Precipitation System (LIPS) enables the detection of specific serum antibodies by immunoprecipitation of recombinant antigens tagged with a luciferase reporter. Here we describe LIPS assays for the quantification of autoantibodies to the H+, K+-ATPase A (ATP4A) and B (ATP4B) subunits, two serological markers of autoimmune atrophic gastritis and pernicious anemia. In particular, we will describe the expression of luciferase-tagged recombinant ATP4A and ATP4B, their immunoprecipitation with test sera, the recovery and washing of immune-complexes with a protein-A coated resin, and the quantification of autoantibodies by addition of a luciferase substrate and the measurement of the light output from captured luciferase-tagged antigens.

Gastric Cancer: an Evolving Disease

PURPOSE OF REVIEW

Prevalence of Helicobacter pylori, the primary risk factor for gastric cancer, is declining globally. Paralleling this trend, gastric cancer incidence is also decreasing. Historically, the populations most affected by this neoplasia have been males, Asians, and groups with low socioeconomic status. This review provides an update on recently published literature regarding changes in gastric cancer epidemiology.

RECENT FINDINGS

Gastric cancer incidence trends vary by age, sex, race/ethnicity, and tumor anatomical location. Overall incidence appears to be leveling off among young birth cohorts in Western populations, where H. pylori has declined considerably. The changes are more prominent for females and for tumors arising beyond the esophageal-gastric junction. The classical incidence pattern of gastric cancer is evolving. While uncertain, several hypotheses may explain the changing burden of disease. The mix of gastric cancer risk factors appears to be shifting, with H. pylori no longer the sole etiological driver. These changes may eliminate the previous predilection of males and lead to increases in overall gastric cancer rates. Analytical studies addressing known and novel factors related to major societal transitions may provide clues to understanding re-emergence of this serious public health problem.

Iron deficiency workup reveals high incidence of autoimmune gastritis with parietal cell antibody as reliable screening test

Iron deficiency (ID) workup is a common challenge for gastrointestinal endoscopy. In premenopausal women current guidelines recommend serologic evaluation of coeliac disease only. Here we systematically tested serologic screening for autoimmune gastritis (AIG) in a large cohort of patients with ID. This is a retrospective analysis of patients who attended an out-patient clinic specialized for ID. Patients with ferritin <50 µg/L or transferrin saturation <15% were included. Laboratory workup included endomysial antibodies and parietal-cell antibodies (PCA). Upper gastrointestinal endoscopy with pH-measurement of gastric juice and histology was performed to confirm positive serologic results. Three hundred seventy-three patients with ID were included, about half of whom were anemic. Patients were predominately female with a median age of 40 (confidence interval 11). Positive endomysial antibodies were found in 4 (1%) patients, elevated levels of PCA (>20 U/mL) were found in 69 (18.5%) patients, PCA >100 U/mL in 23 (6.2%). Twenty-six were followed up by gastroscopy; in 12 of 26 patients the diagnosis of AIG was confirmed by histology with 2 additional patients diagnosed as early and/or questionable AIG. A sensitivity of 93% and a specificity of 98% were estimated for a PCA cut-off of 100 U/mL. In 20 patients gastric pH was measured. Achlorhydria was found in 7 patients all diagnosed with AIG. In this ID cohort AIG is by far more common than coeliac disease. PCA above 100 U/mL are a sensitive and specific cut-off for workup of patients with ID prior to endoscopy. Serologic suspicion of AIG helps preselection of patients for endoscopic workup for ID.

Incidence of cancer (other than gastric cancer) in pernicious anaemia: A systematic review with meta-analysis

BACKGROUND

Pernicious anaemia (PA) is associated with increased gastric cancer risk, but the evidence is conflicting regarding the associated risk of other cancers.

AIM

To systematically determine the incidence rates of gastro-intestinal cancers other than gastric cancers (GI-other-than-GC) and non-gastrointestinal cancers (non-GIC) in PA adults, globally and per tumour site, and the risk associated with PA for GI-other than GC and non-GIC.

METHODS

Studies of PA patients reporting the incidence of GI-other-than-GCs and non-GICs were identified with MEDLINE (PubMed)-EMBASE (from first date available to April 2017). A meta-analysis of annual cancer incidence rates was performed. The outcome was the cumulative incidence of GI-other-than-GCs and non-GICs (ratio between the numbers of new cancer cases identified during the follow-up period and the number of PA patients) and the incidence rate expressed as the rate of events-per-time-unit (person-years).

RESULTS

Of 82,257 PA patients, the pooled incidence rates/100 person-years for non-GCs and non-GICs of 0.27 (95% CI:0.16-0.42) and 0.23 (95% CI:0.22-0.25) were calculated by meta-analysis. Compared to the GLOBOCAN data for the general population from the countries of the included studies, the meta-analysis showed an overall relative risk (RR) of cancer in PA of 0.68 (95% CI:0.48-0.95). PA patients had a lower RR of colorectal, breast, liver, oesophageal, lung, thyroid, ovary, non-melanoma skin and kidney cancers but had a higher RR of biliary tract cancer (1.81:1.21-2.70), multiple myeloma (2.83:1.76-4.55), Hodgkin's lymphoma (3.0:1.35-6.68), non-Hodgkin's lymphoma (2.08: 1.58-2.75), and leukaemia (1.56:1.16-2.12).

CONCLUSION

An overall lower RR of cancers-other-than-gastric-cancer in PA patients but an increased RR of biliary tract cancers and haematological malignancies was observed.

The Relations Among Serum Ghrelin, Motilin and Gastric Emptying and Autonomic Function in Autoimmune Gastritis

BACKGROUND

Gastric emptying (GE) of solids is delayed and autonomic dysfunction is detected in autoimmune gastritis (AIG). The goals of this study were to: (1) compare serum levels of ghrelin and motilin in subjects with delayed and normal GE and (2) investigate whether circulating antimyenteric antibodies (CAA), serum ghrelin levels and motilin levels have any effect on autonomic function.

MATERIALS AND METHODS

Noninvasive cardiovascular reflex tests were used in order to evaluate the autonomic function. GE was evaluated by a standard 2-hour scintigraphic test. Serum ghrelin and motilin levels were tested by enzyme-linked immunosorbent assay and CAA were tested by immunofluorescence.

RESULTS

The serum ghrelin and motilin levels in the patients with delayed GE (n = 22) were significantly decreased compared to the normal GE patients (n = 19), (67.55 ± 8.81 versus 126.79 ± 25.81pg/mL, P < 0.001 and 279.59 ± 111.12 versus 500.42 ± 155.95pg/mL, respectively, P < 0.001). Whereas, the serum ghrelin and motilin levels in the patients with deranged autonomic function (n = 26) were significantly decreased compared to the patients with normal autonomic function (n = 15), (80.73 ± 28.46 versus 127.79 ± 28.06pg/mL, P < 0.001 and 316.92 ± 160.47 versus 490.20 ± 141.02pg/mL, P < 0.001, respectively).  None of the patients were positive for CAA.

CONCLUSIONS

Ghrelin and motilin levels in AIG subjects with delayed GE and deranged autonomic function were significantly decreased. The decrease in serum ghrelin and plasma motilin levels in AIG suggest their potential role in the delayed GE observed in these subjects.

Utility of a laboratory score in the prediction of gastric emptying in autoimmune gastritis patients

OBJECTIVES

Patients with autoimmune gastritis may have symptoms suggestive of delayed gastric emptying. The aim of this study was to explore the predictive value of two scoring systems in the differentiation of delayed gastric emptying in patients with autoimmune gastritis.

METHODS

About 154 patients (106 women) with autoimmune gastritis whose gastric emptying test were available, were analyzed using two laboratory-based scoring systems: 'global score' (hemoglobin, mean corpuscular volume, gastrin, vitamin B₁₂, and chromogranin A) and 'simple score' (hemoglobin, mean corpuscular volume, and gastrin) in order to discriminate delayed and normal gastric emptying.

RESULTS

The mean 'simple score' was 4.82 ± 0.94 for autoimmune gastritis patients with delayed gastric emptying and 0.72 ± 0.60 for patients with normal gastric emptying (p < 0.001). The mean 'global score' was 7.42 ± 0.81 for autoimmune gastritis patients with delayed gastric emptying and 1.176 ± 0.98 (p < 0.001) for patients with normal gastric emptying. There was also a positive correlation between severity of symptoms of patients with autoimmune gastritis and global (r = 0.83, p < 0.001) and simple scores (r = 0.81, p < 0.001).

CONCLUSION

This model may help physicians, while evaluating autoimmune gastritis patients and deciding which patients need gastric emptying test. Gastric emptying study should be ordered in patients who are fulfilling the criteria proposed by these scoring systems.