Association of autoimmune thyroid diseases, chronic atrophic gastritis and gastric carcinoid: experience from a single institution

Effect of gluten-free diet on autoimmune thyroiditis progression in patients with no symptoms or histology of celiac disease: a meta-analysis

Background

Hashimoto's thyroiditis (HT) is the most common autoimmune disease. HT may be associated with nonthyroidal autoimmune diseases, including celiac disease (CD) or other gluten-related conditions (GRC). In the last years, interest about gluten-free diet (GFD) has increased for its supposed extraintestinal anti-inflammatory effect; thus, many patients with HT initiate GFD on their own.

Objectives

The aim of this meta-analysis is to examine all available data in literature about the effect of a GFD on TgAb, TPOAb, TSH, FT4, and FT3 levels in patients with HT and no symptoms or histology of CD.

Methods

The study was conducted according to MOOSE (Meta-analysis Of Observational Studies in Epidemiology). The search was performed on databases PubMed and Scopus. The last search was performed on 7 February 2023. Quality assessment was performed. Meta-analyses were performed using the random-effect model. Hedges' g was used to measure the effect size (ES). Statistical analyses were performed using StataSE 17.

Results

The online search retrieved 409 articles, and 4 studies with a total of 87 patients were finally included for quantitative analysis. The risk of bias was generally low. The mean period of GFD was almost 6 months. The meta-analyses showed reduction in antibody levels with ES: -0.39 for TgAb (95% CI: -0.81 to +0.02; p = 0.06; I² = 46.98%) and -0.40 for TPOAb (95% CI: -0.82 to +0.03; p = 0.07; I² = 47.58%). TSH showed a reduction with ES: -0.35 (95% CI: -0.64 to -0.05; p = 0.02; I² = 0%) and FT4 showed an increase with ES: +0.35% (95% CI: 0.06 to 0.64; p = 0.02; I² = 0%). FT3 did not display variations (ES: 0.05; 95% CI: -0.38 to +0.48; p = 0.82; I² = 51%). The heterogeneity of TgAb, TPOAb, and FT3 data was solved performing sub-analyses between patients with or without GRC (TgAb p = 0.02; TPOAb p = 0.02; FT3 p = 0.04) and only for FT3, performing a sub-analysis between patients taking and not taking LT4 (p = 0.03).

Conclusion

This is the first meta-analysis investigating the effect of GFD on HT. Our results seem to indicate a positive effect of the gluten deprivation on thyroid function and its inflammation, particularly in patients with HT and GRC. However, current lines of evidence are not yet sufficient to recommend this dietary approach to all patients with a diagnosis of HT.

Vitamin B12 levels in thyroid disorders: A systematic review and meta-analysis

Background and aims

Numerous studies have found an association between vitamin deficiency and thyroid disorders (TD). The presence of anti-parietal cell antibodies is indicative of reduced ability to absorb vitamin B12. Thus, this study reviewed the existing studies with the objective of assessing differences in the serum levels of vitamin B12 among patients with and without TD, the frequency of vitamin B12 deficiency in patients with TD, and the presence of anti-parietal cell antibodies in patients with TD.

Methods

A meta-analysis of random-effects model was conducted to calculate pooled frequencies, mean differences (MD), and their respective 95% confidence intervals (CI). We identified 64 studies that met our inclusion criteria (n = 28597).

Results

We found that patients with hypothyroidism had lower vitamin B12 levels than healthy participants (MD: -60.67 pg/mL; 95% CI: -107.31 to -14.03 pg/mL; p = 0.01). No significant differences in vitamin B12 levels were observed between healthy participants and patients with hyperthyroidism (p = 0.78), autoimmune thyroid disease (AITD) (p = 0.22), or subclinical hypothyroidism (SH) (p = 0.79). The frequencies of vitamin B12 deficiency among patients with hypothyroidism, hyperthyroidism, SH, and AITD were 27%, 6%, 27%, and 18%, respectively.

Conclusions

Patients with hypothyroidism had lower levels of vitamin B12 than healthy participants. No significant differences were observed between vitamin B12 levels and hyperthyroidism, AITD, or SH.

Systematic Review Registration

https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=324422, identifier (CRD42022324422).

Management of upper gastrointestinal symptoms in patients with autoimmune gastritis

PURPOSE OF REVIEW

Autoimmune gastritis is characterized by atrophy of acid secreting parietal cells resulting in achlorhydria. Upper gastrointestinal symptoms are common in autoimmune gastritis and frequently result in prescriptions for acid suppressant medications despite the inability of the stomach to secrete acid. Evidence-based recommendations for management of gastrointestinal symptoms in autoimmune gastritis are lacking.

RECENT FINDINGS

The most common symptoms in patients with autoimmune gastritis are dyspepsia, heartburn, and regurgitation. Gastroesophageal reflux should be confirmed by pH-impedance testing and is typically weakly acid or alkaline. Therapy for reflux focuses on mechanical prevention of reflux (i.e., elevation of the head of the bed and alginates) or when severe, antireflux surgery. The etiology of dyspepsia in autoimmune gastritis is unclear and largely unstudied. In the first half of the 20th century, oral administration of acid to "aid digestion" was widely used with reported success. However, randomized, placebo-controlled trials are lacking. Here, we provide suggestions for attempting gastric acidification therapy.

SUMMARY

Upper GI symptoms are common in autoimmune gastritis. Their pathogenesis and therapy remain incompletely understood. Acid suppressant medications are useless and should be discontinued. A trial of acid replacement therapy is recommended especially in the form of placebo-controlled trials.

Hashimoto Thyroiditis, Anti-Parietal Cell Antibodies: Associations With Autoimmune Diseases and Malignancies

BACKGROUND

Hashimoto thyroiditis (HT) is an autoimmune disease which may result in extensive damage of the thyroid gland. Chronic atrophic gastritis (CAG), is the most frequent HT-associated disorder, with anti-parietal cell autoantibodies (APCA) being a screening test for autoimmune CAG. The aim of this study was to investigate, in a cohort of HT patients: a) the prevalence of APCA in an attempt to define their clinical phenotype and b) any possible associations of APCA with other autoimmune diseases and malignancies.

METHODS

This is a single-center, case-control study, conducted at a University Hospital. The study included patients with HT diagnosed between November 2017 and November 2020. Excluded were patients <18 years old, with sonographic features of HT but negative thyroid peroxidase (TPOAbs) or thyroglobulin autoantibodies (TgAbs), Graves' disease, Down or Turner's syndrome.

RESULTS

A total of 840 patients with HT were included in the study, from whom 180 (21.4%) had positive APCA. A total of 79 patients (9.4%) had one or more organ-specific autoimmune diseases and 61 (7.3%) had a systemic autoimmune disease. Autoimmune diseases were more frequent in female than in male patients (17.9% versus 10.9%, p = 0.05). APCA-positive patients were older than APCA-negative (54.1 ± 13.5 versus 49.0 ± 14.6, p <0.001) and had more often positive TPOAbs (93.3% versus 83.9%, p=0.001). Gastric neoplasms were documented only in APCA-positive patients (p <0.001). A higher frequency of organ-specific autoimmune diseases was observed in the APCA-positive group (14.4% versus 8%, p = 0.024). In the subgroup of patients with additional autoimmune diseases (n = 140), younger age and positive APCA were independently associated with the presence of organ-specific autoimmunity (OR 0.954, 95% CI 0.927-0.982 and OR 3.100, 95% CI 1.256-7.652, respectively). Papillary thyroid cancer (PTC) occurred in 3.5% of patients (26/29 women). Positive family history for thyroid autoimmunity and negative TPOAbs were the only independent risk factors for PTC among women (OR 3.228, 95% CI 1.173-8.887 and 0.315, 95% 0.113-0.881, respectively).

CONCLUSION

This study reveals for the first time an association of APCA with organ-specific autoimmunity in HT patients. APCA together with patient age were independently associated with the presence of organ-specific autoimmunity. Finally, this study showed an association between APCA and gastric neoplasms in these patients.

Screening of Organ-Specific Autoantibodies in a Large Cohort of Patients with Autoimmune Thyroid Diseases

Background: Autoimmune diseases tend to cluster in the same individual or in families. Four types of autoimmune polyglandular syndromes (APS) have been described based on the combination of endocrine and/or non-endocrine autoimmune diseases. In particular, type-3 APS is defined by the association of an autoimmune thyroid disease (ATD) and other autoimmune diseases and has a multifactorial etiology. The natural history of autoimmune diseases is characterized by three stages: potential, subclinical, and clinical. Methods: To determine the prevalence of organ-specific autoantibodies (anti-adrenal, anti-ovary [StCA], anti-pituitary [APA], anti-parietal cells [PCA], anti-tissue transglutaminase [tTGAb], anti-mitochondrial [AMA], anti-glutamic acid decarboxylase [GADA], anti-nicotinic acetylcholine receptor) in patients with ATD and to define the stage of the disease in patients with positive autoantibodies. From January 2016 to November 2018, 1502 patients (1302 female; age 52.7 ± 14.7 [mean ± standard deviation] years, range 18-86 years) with ATD (1285/1502 [85.6%] with chronic autoimmune thyroiditis and 217/1502 [14.4%] with Graves' disease) were prospectively enrolled. Results: The most common organ-specific autoantibodies were PCA (6.99%) and GADA (2.83%), while the prevalence of the remaining autoantibodies was ≤1%. All autoimmune diseases, but celiac disease, were predominant at the potential stage. Sex, ATD type, smoking habit, and coexistence of other autoimmune diseases correlated with the susceptibility to develop chronic atrophic gastritis (CAG) or autoimmune diabetes mellitus. Conclusions: The association between ATD and CAG was the most common manifestation of type-3 APS, mainly at the potential stage, that could lead to appropriate follow-up for early detection and timely treatment of the disease.

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.

Low Pepsinogen I/II Ratio and High Gastrin-17 Levels Typify Chronic Atrophic Autoimmune Gastritis Patients With Gastric Neuroendocrine Tumors

Chronic atrophic autoimmune gastritis (CAAG) can lead to the development of gastric neuroendocrine tumors (gNETs) and can be accompanied by other autoimmune diseases. This study aimed to determine, in CAAG patients, the association of gNET development, the prevalence of autoimmune diseases other than CAAG, the association of autoimmunity, and gNET development with pepsinogen I, II, gastrin-17, and Helicobacter pylori infection analysis.

Autoimmune atrophic gastritis: The role of Helicobacter pylori infection in children

BACKGROUND

Autoimmune atrophic gastritis (AIG) is very rare in children. Despite a better understanding of histopathologic changes and serological markers in this disease, underlying etiopathogenic mechanisms and the effect of Helicobacter pylori (H pylori) infection are not well known. We aimed to investigate the relation between AIG and H pylori infection in children.

MATERIALS AND METHODS

We evaluated the presence of AIG and H pylori infection in fifty-three patients with positive antiparietal cell antibody (APCA). Demographic data, clinical symptoms, laboratory and endoscopic findings, histopathology, and presence of H pylori were recorded.

RESULTS

The children were aged between 5 and 18 years, and 28 (52.8%) of them were male. Mean age was 14.7 ± 2.6 years (median: 15.3; min-max: 5.2-18), and 10 (18.8%) of them had AIG confirmed by histopathology. In the AIG group, the duration of vitamin B12 deficiency was longer (P = .022), hemoglobin levels were lower (P = .018), and APCA (P = .039) and gastrin (P = .002) levels were higher than those in the non-AIG group. Endoscopic findings were similar between the two groups. Intestinal metaplasia was higher (P = .018) in the AIG group. None of the patients in the AIG group had H pylori infection (P = .004). One patient in the AIG group had enterochromaffin-like cell hyperplasia.

CONCLUSIONS

Our results show that, in children, H pylori infection may not play a role in AIG. AIG could be associated with vitamin B12 deficiency, iron deficiency, and APCA positivity in children. APCA and gastrin levels should be investigated for the early diagnosis of AIG and intestinal metaplasia.

Workup of Gastroenteropancreatic Neuroendocrine Tumors

Neuroendocrine tumors of the gastrointestinal tract or pancreas are rare. Their presentation overlaps with other intra-abdominal neoplasms, but can have unique features. The workup involves recognition of unusual clinical features associated with the tumors, imaging, analysis of blood or urine concentrations, and biopsy. Functional imaging takes advantage of the neuroendocrine tumor-specific expression of somatostatin receptors. There are characteristic features supporting the diagnosis on contrast-enhanced cross-sectional imaging. The use of tumor markers for biochemical diagnosis requires an understanding of the confounding variables affecting these assays. There are unique and specific immunohistochemical staining and grading requirements for appropriate diagnosis of these tumors.

Changes in glucose-lipid metabolism, insulin resistance, and inflammatory factors in patients with autoimmune thyroid disease

Background

Autoimmune thyroid disease (AITD) is a common organ‐specific autoimmune disorder, and genetic, environmental, and endogenous factors are responsible for initiation of thyroid autoimmunity. Some AITD patients suffer from a certain degree of glucose‐lipid metabolism disorder. This study aims to explore the changes in glucose‐lipid metabolism, insulin resistance, and inflammatory factors in patients with AITD.

Methods

A total of 91 patients with Hashimoto's thyroiditis were retrospectively analyzed and divided into hypothyroidism group (n = 42) and normal thyroid group (n = 49), while 50 healthy people were selected as control group. The changes in glucose‐lipid metabolism, insulin resistance, and inflammatory factors in each group were compared, and their correlations with the thyroid function were analyzed.

Results

The levels of serum interleukin‐6 (IL‐6), tumor necrosis factor‐α (TNF‐α), IL‐12, IL‐10, (FINS), and homeostasis model assessment of insulin resistance (HOMA‐IR) were gradually declined in sequence of hypothyroidism group, normal thyroid group, and control group (P < 0.05). In hypothyroidism group, the levels of serum‐free triiodothyronine (FT3), free thyroxine (FT4), (TC), triglyceride (TG), and low‐density lipoprotein cholesterol (LDL‐C) were significantly lower than those in normal thyroid group (P < 0.05), while the level of serum thyroid stimulating hormone (TSH) was significantly higher than that in normal thyroid group (P < 0.05). However, the fasting blood glucose and 2‐hour postprandial blood glucose levels had no statistically significant differences among the three groups (P > 0.05).

Conclusion

Autoimmune thyroid disease patients are prone to fat metabolism disorder, and the serum thyroid hormone level has a close correlation with blood lipid metabolism, insulin metabolism, and inflammatory factors.

A Case of Oculocutaneous Albinism in a Patient with Hashimoto's Thyroiditis

BACKGROUND

Oculocutaneous albinism (OCA) is a heterogeneous autosomal recessive disorder characterized by reduced or absent melanin synthesis. Its prevalence is approximately one in 17,000 individuals worldwide. OCA causes a complete or partial absence of pigment in the skin, hair, and eyes. Reduction of melanin in the eyes results in reduced visual acuity, photophobia, and nystagmus. To our knowledge, the coexistence of albinism and thyroid autoimmune diseases has not been reported.

CASE REPORT

A 37-year-old male with OCA came to our observation for a familial history of autoimmune thyroiditis. He complained with mild asthenia. His brother was affected by OCA and autoimmune thyroiditis. Physical examination revealed the presence of fair skin, platinum white hair, and hypopigmentation of the iris. Laboratory data revealed the presence of subclinical hypothyroidism with positive serum anti-thyroid antibodies. Neck ultrasonography showed a markedly heterogeneously hypoechoic pattern of the thyroid, with a honeycomb-like appearance.

DISCUSSION

In the majority of cases, OCA in Caucasians is caused by mutations in the tyrosinase gene. The tyrosinase peptide is normally expressed on the surface of melanocytes, although recent studies have shown its presence in thyroid follicular epithelial cells of patients with Hashimoto's thyroiditis. Therefore, although the mechanism is unclear, the present case report may suggest a pathogenetic link between OCA and Hashimoto's thyroiditis.

How much of the predisposition to Hashimoto's thyroiditis can be explained based on previously reported associations?

PURPOSE

Our insight in the genetics of Hashimoto's thyroiditis (HT) has become clearer through information provided by genome-wide association studies and candidate gene studies, but remains still not fully understood. Our aim was to assess how many different genetic risk variants contribute to the development of HT.

METHODS

147 HT cases (10.2% men) and 147 controls (13.6% men) were qualified for the analysis. Intrinsic and environmental factors were controlled for. Polymorphisms (SNP) were chosen based on the literature and included markers of the genes PTPN22, CTLA4, TG, TPO among others, and of genomic regions pointed by GWAS studies. SNP were typed on a microarray. Variants in the HLA-DRB1 gene were identified by Sanger sequencing.

RESULTS

Multivariate predisposition to HT was modeled. Based on the investigated group, a model of seven variables was obtained. The variability explained by this model was assessed at only 5.4821% (p = 2 × 10^-6), which indicates that many dozens of factors are required simultaneously to explain HT predisposition.

CONCLUSIONS

We analyzed genetic regions commonly and most significantly associated with autoimmune thyroid disorders in the literature, on a carefully selected cohort. Our results indicated a lack of possibility to predict the risk of HT development, even with a multivariate model. We therefore conclude that strong associations of single genetic regions with HT should be interpreted with great caution. We believe that a change in the attitude towards genetic association analyses of HT predisposition is necessary. Studies including multiple factors simultaneously are needed to unravel the intricacies of genetic associations with HT.

Association between vitamin D deficiency and risk of thyroid cancer: a case-control study and a meta-analysis

PURPOSE

Although vitamin D is reportedly associated with various cancers, the association between vitamin D and thyroid cancer is indefinite. We aimed to investigate whether this association applies to thyroid cancer (TC).

METHODS

A total of 276 Chinese Han people were recruited in a current matched case-control study. Multivariable conditional logistic regression was computed to estimate the association between plasma 25(OH)D and papillary thyroid cancer (PTC). In addition, we searched relevant studies in PubMed and Web of Science databases before December 2017 to conduct a meta-analysis.

RESULTS

In our case-control study, plasma 25(OH)D concentration was inversely associated with PTC risk (highest tertile vs lowest tertile: adjusted OR = 0.25; 95% CI 0.10, 0.61; P_trend = 0.003). This association was independent of body mass index and physical activity (all adjusted P_interaction > 0.05). A total of 11 studies were included in the meta-analysis, among which ten studies have been published and one was our case-control study. Compared with 25(OH)D non-deficient group, the pooled OR of TC was 1.42 (95% CI 1.17, 1.73) in the deficient group. Similarly, blood 25(OH)D levels in patients with TC were tend to be lower than those in the controls (SMD = - 0.20, 95% CI - 0.36, - 0.03).

CONCLUSIONS

A high level of circulating 25(OH)D was associated with a decreased TC risk. This association has important significance in public health and should, therefore, be further studied.

Exploring the potential pharmacodynamic material basis and pharmacologic mechanism of the Fufang-Xialian-Capsule in chronic atrophic gastritis by network pharmacology approach based on the components absorbed into the blood

In this study, a new network pharmacology approach based on the components absorbed into the blood was used to investigate the pharmacodynamic material basis and the pharmacologic mechanism of the Fufang-Xialian-Capsule (FXL) in treating chronic atrophic gastritis (CAG). Initially, we confirmed the components absorbed into the blood by ultra-high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry. Then, the network approach, which was based on the results of components absorbed into the blood, was used to analyse the pharmacodynamic material basis and the pharmacologic mechanism of FXL on treating CAG. As a result, 22 absorbed components were found in rat plasma. Given the results of the absorption analysis of the components, eight pathways associated with CAG development were found. The targets linked to these pathways are the drug targets of FXL in CAG treatment. The components associated with these targets are the potential pharmacodynamic material basis and exert synergy in regulating pathways during CAG treatment.

HIGH-RISK GASTRIC PATHOLOGY AND PREVALENT AUTOIMMUNE DISEASES IN PATIENTS WITH PERNICIOUS ANEMIA

OBJECTIVE

Pernicious anemia (PA) develops from atrophic gastritis due to autoimmune destruction of parietal cells and results in achlorhydria, vitamin B12 and iron deficiencies, anemia, neurologic deficits, and premalignant and malignant stomach lesions. We report the presentation, diagnosis and gastric complications of PA in patients from an endocrinology practice.

METHODS

Thirty-four patients (31 female, 3 male) with PA who underwent esophagogastroduodenoscopy (EGD) or gastrectomy were identified. Pertinent clinical, laboratory, and pathology findings were reviewed and summarized.

RESULTS

The mean age of patients was 58.6 ± 14.2 years; the onset of PA was age 50.2 ± 15.3 years. Anemia reflected vitamin B12 and/or iron deficiencies. Parietal cell antibodies (PCA) were detected in 97% of patients, and intrinsic factor blocking antibody (IFBA) was found in 52%. Fasting gastrin and chromogranin A levels were elevated (1,518.0 ± 1,588.3 pg/mL, and 504.9.1 ± 1,524.9 ng/mL respectively). Autoimmune or immunologic diseases (AIDs) were present in 32/34 patients. Stomach pathology showed premalignant or malignant lesions in 26 patients, including gastric neuroendocrine tumors (GNETs) in 6 and adenocarcinoma in 1. One patient presented with neurologic symptoms and subacute combined degeneration of the posterior column of the spinal cord.

CONCLUSION

PA should be suspected in patients with unexplained anemia or neurologic symptoms. The diagnosis of PA relies on fasting gastrin and gastric auto-antibody testing, in addition to hematologic evaluation. EGD with measurement of gastric pH and biopsies of the fundus and antrum identifies patients with achlorhydria, atrophic gastritis, and premalignant and malignant stomach lesions. EGD surveillance of patients with high-risk stomach lesions is recommended.

ABBREVIATIONS

AID = autoimmune or immunologic disease; EGD = esophagogastroduodenoscopy; GNET = gastric neuroendocrine tumor; IFBA = intrinsic factor blocking antibody; PA = pernicious anemia; PCA = parietal cell antibody; T1D = type 1 diabetes.

Diagnosis and management of treatment-refractory hypothyroidism: an expert consensus report

There is a frequently encountered subset of hypothyroid patients who are refractory to standard thyroid hormone replacement treatment and require unexpectedly high doses of levothyroxine. In addition to clinical situations where hypothyroid patients are non-compliant, or where there is the possibility of excipient-induced disease exacerbation (gluten/celiac disease), therapeutic failure may be due to impaired absorption of the administered drug. The common approach to managing patients with unusual thyroxine needs is to escalate the dose of levothyroxine until targeted TSH levels are achieved. This approach can increase the risk for prolonged exposure to supratherapeutic doses of levothyroxine, which increase the chances of adverse outcomes. Repeated adjustments of levothyroxine can also escalate the costs of treatment, as frequent office visits and laboratory tests are required to determine and maintain the desired dose. Clinicians should take a systematic approach to managing patients whom they suspect of having treatment-refractory hypothyroidism. This may include searching for, and adjusting, occult medical conditions and/or other factors that may affect the absorption of levothyroxine, before up-titrating the dose of traditional levothyroxine therapy. Depending on the underlying pathology, another approach that may be considered is to try alternative formulations of levothyroxine that are less susceptible to intolerance issues related to excipients, or, in some cases, to malabsorption. The early discovery of these factors via a thoughtful patient work-up may avoid unnecessary thyroid medication adjustments and their consequences for both patients and clinicians.

Autoimmune atrophic gastritis: current perspectives

At present there is no universally accepted classification for gastritis. The first successful classification (The Sydney System) that is still commonly used by medical professionals was first introduced by Misiewicz et al in Sydney in 1990. In fact, it was the first detailed classification after the discovery of Helicobacter pylori by Warren and Marshall in 1982. In 1994, the Updated Sydney System was proposed during the International Workshop on the Histopathology of Gastritis followed by the publication in The American Journal of Surgical Pathology by Dixon et al. Using the new classification, distinction between atrophic and nonatrophic gastritis was revised, and the visual scale grading was incorporated. According to the Updated Sydney System Classification, atrophic gastritis is categorized into multifocal (H. pylori, environmental factors, specific diet) and corpus-predominant (autoimmune). Since metaplasia is a key histological characteristic in patients with atrophic gastritis, it has been recommended to use the word “metaplastic” in both variants of atrophic gastritis: autoimmune metaplastic atrophic gastritis (AMAG) and environmental metaplastic atrophic gastritis. Although there are many overlaps in the course of the disease and distinction between those two entities may be challenging, the aim of this review article was to describe the etiology, epidemiology, pathogenesis, diagnosis, clinical manifestations and treatment in patients with AMAG. However, it is important to mention that H. pylori is the most common etiologic factor for the development of gastritis in the world.

Autoimmune metaplastic atrophic gastritis in chinese: a study of 320 patients at a large tertiary medical center

OBJECTIVES

Autoimmune metaplastic atrophic gastritis (AMAG) is an uncommon disease worldwide and may predispose to gastric carcinoid tumors or adenocarcinomas. The aims of this study were to outline the clinical characteristics of Chinese AMAG patients, including demographic pattern, hematologic features, and gastroscopic and histopathologic findings.

PATIENTS AND METHODS

A total of 320 Chinese patients with AMAG, from January 2007 to December 2014, were reviewed in a regional hospital of China.

RESULTS

Of the 320 AMAG patients, the mean age was 60.6 ± 12.3 years [range 26-86; 206 (64.4%) women]. The coarse annual detection rate was 0.9%. Anemia was present in only 19.3% patients (53/275) and 3.5% (11/315) AMAG patients also had primary biliary cirrhosis. One hundred and thirty-six had endoscopically identifiable lesions. These lesions consisted of 130 polypoid lesions (63 hyperplastic polyps, 2 oxyntic mucosa pseudopolyps, 2 intestinal-type gastric adenomas, 2 fundic gland polyps, 5 concurrent polyps, 14 well-differentiated neuroendocrine neoplasms, 7 submucosal tumors and 35 chronic gastritis), 6 adenocarcinomas. The detection rate of atrophy and intestinal metaplasia in antral mucosa were 47.2 and 37.5%, respectively.

CONCLUSIONS

AMAG is more frequent than expected in China and display a female predominance, accompanied with other autoimmune disorders. AMAG should be paid more attention by clinicians through a multidisciplinary team approach.