Lymphocytic gastritis: association with etiology and topology

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

INTRODUCTION

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

MATERIALS AND METHODS

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

RESULTS

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

CONCLUSIONS

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

[Inflammatory bowel diseases and upper gastrointestinal tract]

Inflammatory bowel diseases (IBD), Crohn's disease and ulcerative colitis are inflammatory diseases with a flare-up evolution and an unknown etiology. Inflammatory lesions of the upper gastrointestinal tract are more and more often described in Crohn's disease and ulcerative colitis. The aim of this article was to review the inflammatory lesions of the esophagus, stomach and duodenum currently described in the IBD.

Helicobacter pylori-negative Chronic Gastritis in Children: A Systematic Review

OBJECTIVES

To systematically review the current evidence on Helicobacter pylori-negative chronic gastritis including natural history, available therapies and outcomes.

METHODS

Articles providing data on the prevalence, treatment or outcomes of Helicobacter pylori-negative gastritis were identified through a systematic search in the MEDLINE and EMBASE databases. All original research articles from human studies until October 31, 2021, were included.

RESULTS

A total of 54 studies were included consisted of eosinophilic gastritis (n = 9), autoimmune gastritis (n = 11), collagenous gastritis (n = 16), focally enhanced gastritis (n = 6), lymphocytic gastritis (n = 5) and other causes including idiopathic gastritis and chronic renal failure related (n = 7). Most of the included studies were either cross-sectional or longitudinal cohorts except for collagenous gastritis, which mainly included case reports and case series. The prevalence of paediatric eosinophilic gastritis ranges between 5 and 7/100,000 and patients have generally favourable outcome with 50% to 70% clinical and histological response to either corticosteroids or elimination diets. Autoimmune gastritis and collagenous gastritis are extremely rare entities, commonly present with refractory iron deficiency anaemia, while lymphocytic gastritis is relatively common (10%-45%) in children with coeliac disease. Data on treatments and outcomes of autoimmune, collagenous, and focally enhanced gastritis are lacking with limited data implying poor response to therapy in the former 2 diagnoses.

CONCLUSIONS

Helicobacter pylori-negative gastritis is uncommonly reported, mainly in small cohorts, mixed adult-paediatric cohorts or as sporadic case reports. As common symptoms are not specific, thus not always result in an endoscopic evaluation, the true prevalence of these distinct disorders may be underestimated, and thus under reported.

Upper Gastrointestinal Tract Involvement in Inflammatory Bowel Diseases: Histologic Clues and Pitfalls

The upper gastrointestinal (UGI) manifestations of inflammatory bowel diseases (IBDs) are frequently obscured by classic ileal and colonic symptoms and are reported to involve only 0.5% to 4% of adult patients. However, because of the improvement of endoscopic techniques and the growing use of esophagogastroduodenososcopy with biopsy, both asymptomatic and clinically significant esophageal, gastric, and duodenal manifestations are increasingly recognized. The UGI involvement in IBD was historically synonymous with Crohn's disease (CD), but the doctrine of ulcerative colitis (UC) being limited to the colon has been challenged, and UC-related gastroduodenal lesions have been reported. The diagnosis of UGI IBD should ideally rely on a combination of the clinical history, endoscopic picture, and histologic features. Although endoscopic changes such as aphthoid or longitudinal ulcers and bamboo-joint-like pattern are suggestive of CD, histologic evaluation increases the sensitivity of the IBD diagnosis since histologic alterations may be present in endoscopically unremarkable mucosa. Conversely, in many cases, the histologic findings are nonspecific, and the knowledge of clinical history is vital for reaching an accurate diagnosis. The presence of epithelioid granuloma is highly suggestive of CD but is present in a minority of CD cases; thus, pathologists should be aware of how to diagnose UGI IBD in the absence of granulomata. This article reviews the most important clinical, endoscopic, and histologic features of IBD-associated esophagitis, gastritis, and duodenitis, as well as the IBD-related manifestations in the biliary tract and the postcolectomy setting.

Lymphocytic gastritis and its relationships with other gastrointestinal disorders

BACKGROUND

Lymphocytic gastritis (LyG) is a histopathologic finding of unknown clinical relevance.

AIMS

To explore the clinical epidemiology of LyG and its associations with Helicobacter pylori (Hp) infection, coeliac disease (CD) and microscopic colitis (MC) METHODS: In a cross-sectional study, the demographic, clinical, and histopathologic data of patients with and without LyG were compared. Between 2008 and 2020, 1.5 million patients with endoscopic biopsies of the gastroduodenal mucosa were extracted from a database. LyG diagnoses were reviewed to collect detailed information regarding its topographic distribution within the stomach. In a large subgroup of 400 000 patients, tissue samples from the colon were also available.

RESULTS

Of 1 481 336 patients, 341 had LyG with Hp and 2697 had Hp-negative LyG (with an overall prevalence of 0.21%). In patients with Hp-negative LyG, 450 (17%) had corpus-predominant LyG, 1068 antrum-predominant LyG (40%), and 1179 pangastric LyG (44%). LyG was more common in males and in subjects aged 50-70 years. There was no significant ethnic variation. Anaemia, diarrhoea, and weight loss were more common in patients with than without LyG. In 35% and 19% of patients, LyG was associated with CD and MC, respectively. All 72 patients with Hp-positive LyG and 280 of 310 patients with Hp-negative LyG with follow-up biopsies became free of LyG within a year.

CONCLUSIONS

Most cases of LyG may represent a self-limited expression, frequently associated with other GI conditions, such as Hp infection, CD, and MC. In most patients, LyG is likely to resolve within a year after its initial diagnosis.

Helicobacter Infection and Gastric Adenoma

Background: We aimed to provide insight into the actual frequencies of gastric adenoma types and their association with gastritis status and associated mucosal changes with a focus on Helicobacter infection and the operative link on gastritis assessment (OLGA)/operative link on gastric intestinal metaplasia assessment (OLGIM) staging. Methods: From the archive of the Institute of Pathology in Bayreuth, we collected a consecutive series of 1058 gastric adenomas diagnosed between 1987 and 2017. Clinicopathological parameters retrieved from diagnostic reports included adenoma type and localization, associated mucosal changes in antrum and corpus (i.e., type of gastritis, the extent of intestinal metaplasia and atrophy), gender, date of birth, and date of diagnosis. Results: Intestinal-type adenoma was the most frequent adenoma (89.1%), followed by foveolar-type adenoma (4.3%), pyloric gland adenoma (3.4%), adenomas associated with hereditary tumor syndromes (2.8%), and oxyntic gland adenoma (0.4%). Adenomas were found in the background of Helicobacter pylori (H. pylori) gastritis in 23.9%, Ex-H. pylori gastritis in 36.0%, autoimmune gastritis in 24.8%, chemical reactive gastritis in 7.4%, and others in 0.1%. More than 70% of patients with gastric adenomas had low-risk stages in OLGA and OLGIM. Conclusions: We found a higher frequency of foveolar-type adenoma than anticipated from the literature. It needs to be questioned whether OLGA/OLGIM staging can be applied to all patients.

The coeliac stomach: A review of the literature

Beyond the small intestine, coeliac disease (CeD) may affect other gastrointestinal tracts, including the stomach. However, various studies have reported conflicting results regarding the association between CeD and gastric manifestations. The aim of this study was to analyze the existing literature on gastric involvement in CeD. A literature search was conducted in bibliographic databases of Embase, PubMed, Scopus, and Web of Science. Studies reporting the association between CeD and gastric disorders were examined in detail and are fully described in the review. Both in children and adults, a strong correlation between lymphocytic gastritis and CeD was found at CeD diagnosis, and lymphocytic gastritis seemed to improve on a gluten-free diet. Most of the literature described a lower risk of gastritis related to Helicobacter pylori infection in CeD subjects compared to controls. However, due to the discordance among studies in terms of study design and population, a clear association could not be determined. Finally, the relationship between CeD and reflux or dyspepsia has yet to be defined, as well as the association between CeD and autoimmune gastritis. CeD appears to be a multiform entity associated with different gastric disorders with a different degree of relationship. Thus, gastric biopsies should be routinely taken during upper endoscopy in CeD patients.

Topography, morphology, and etiology of lymphocytic gastritis: a single institution experience

Lymphocytic gastritis (LG) is an uncommon reaction pattern of gastric injury characterized by intraepithelial lymphocytosis of the surface foveolar epithelium and chronic inflammation in the lamina propria. It most commonly occurs in association with gluten-sensitive enteropathy, Helicobacter pylori gastritis, non-steroidal anti-inflammatory drugs, and microscopic colitis. While the topography of LG has been described in gluten-sensitive enteropathy and H. pylori infection, no definite morphologic features have been used to further subcategorize LG based on possible etiologies. Furthermore, new immunotherapy agents have been associated with lymphocytic infiltrate in the gastrointestinal tract, but their association with LG has not been reported. Cases of LG were collected from our institution in the period between August 2011 and September 2017. The topography of LG and morphologic features such as glandular microabscesses, intestinal metaplasia, lymphoid aggregates, surface vs pit distribution of lymphocytes, and number of intraepithelial lymphocytes per 100 epithelial cells were assessed for each case using the updated Sydney System where applicable. Twenty-seven cases of LG were identified in the recent 6-year period at our institution. Gluten-sensitive enteropathy is the main reported cause of LG followed by NSAID injury. Cases of LG associated with gluten-sensitive enteropathy are antral predominant, those associated with H. pylori are body predominant, and those occurring in the setting of NSAID injury show pangastritis. Glandular microabscesses are observed in all cases of LG associated with H. pylori, and not in the setting of GSE or NSAID injury. In addition, a case of LG associated with melanoma immunotherapy has been identified. Topography and morphology of lymphocytic gastritis may point to the cause of injury, allowing for proper treatment of the underlying disease.

Lymphocytic gastritis induced by pembrolizumab in a patient with metastatic melanoma

Immune checkpoint inhibitors such as programmed cell death-1 inhibitor pembrolizumab have been shown to be effective in metastatic malignancies such as advanced melanoma. Immune-related adverse effects on multiple organs have been described, such as colitis, skin rash, and hypothyroidism. We present the case of a 44-year-old man with advanced melanoma and recurrent lung metastases who developed symptoms of dyspepsia and gastroesophageal reflux disease after 1 month of therapy with pembrolizumab. Gastric biopsy showed histologic features consistent with lymphocytic gastritis, which was absent on a biopsy 2 months before initiation of therapy. Lymphocytic infiltrates likely secondary to increased autoimmunity after use of immunotherapy have been observed in the colon; however, such histologic findings in the upper gastrointestinal tract have yet to be described. Here, we present a case of lymphocytic gastritis in a patient treated with pembrolizumab, suggesting a new manifestation of toxicity.

Effects of force-feeding on immunology, digestive function and oxidative stress in the duodenal and jejunal mucosa of Pekin ducks

Force-feeding was considered as a traditional high-efficiency approach to improve growth performance and accelerate fat deposition of Pekin ducks. However, force-feeding is a serious violation of international advocacy on animal welfare, because it can induce serious injuries to animals, such as damages to the digestive tract, effects on immunity and even severe oxidative stress. Therefore, it is urgent to stop force-feeding. The aim of this study was to determine the effects of force feeding on immune function, digestive function and oxidative stress in the mucosa of duodenum and jejunum of Pekin ducks. A total of 500 ducks were randomly divided into two groups. The control group was allowed to feed freely on a basal diet. The experimental group was force-fed by inserting a plastic feeding tube 8 to 10 inches long down the esophagus for 6 days. Compared with the control group, there was a significant (P<0.05) increase in serum diamine oxidase, d-lactic acid, endotoxin and corticosterone levels in the force-feeding group. The crypt depth in duodenum and jejunum showed significant differences (P<0.05) between the two groups and the intestinal villus epithelium cell was severely damaged in force-feeding group. Similarly, the activities of digestive enzymes as well as the levels of immune function in the duodenal and jejunal mucosa in the force-feeding group were significantly higher than the control group (P<0.05). However, there was a significant decrease in the superoxide dismutase, glutathione peroxidase and catalase levels with a marked increase in malondialdehyde level in duodenal and jejunal mucosa (P<0.05). In summary, at the end of the fattening period with force-feeding for 6 days, Pekin ducks experienced an adverse effect on the integrity of their duodenal and jejunal mucosa epithelium cell as well as their immune function and antioxidant capacity of Pekin ducks but also had improvement in digestive enzyme activities.

Pathologic Features of Infectious Gastritis

This manuscript presents a review of infectious causes of gastritis aimed at the practicing anatomic pathologist. We shall highlight unique histologic findings and clinical attributes that will assist those analyzing endoscopically obtained mucosal biopsies of the stomach or resection specimens.

Sensing Bacterial-Induced DNA Damaging Effects via Natural Killer Group 2 Member D Immune Receptor: From Dysbiosis to Autoimmunity and Carcinogenesis

The human genome is constantly exposed to exogenous and endogenous DNA damaging factors that frequently cause DNA damages. Unless repaired, damaged DNA can result in deleterious mutations capable of causing malignant transformation. Accordingly, cells have developed an advanced and effective surveillance system, the DNA damage response (DDR) pathway, which maintains genetic integrity. In addition to well-defined outcomes, such as cell cycle arrest, apoptosis, and senescence, another consequence of DDR activation is the induction of natural killer group 2 member D ligands (NKG2D-Ls) on the surface of stressed cells. Consequently, NKG2D-Ls-expressing cells are recognized and eliminated by NKG2D receptor-expressing immune cells, including NK cells, and various subsets of T-cells. Recent pieces of evidence indicate that commensal microbial imbalance (known as dysbiosis) can trigger DDR activation in host cells, which may result in sustained inflammatory responses. Therefore, dysbiosis can be seen as an important source of DNA damage agents that may be partially responsible for the overexpression of NKG2D-Ls on intestinal epithelial cells that is frequently observed in patients with inflammatory bowel disease and other disorders associated with altered human microbiota, including the development of colorectal cancer. In this article, we discuss recent evidence that appears to link an altered human microbiota with autoimmunity and carcinogenesis via the activation of DDR signals and the induction of NKG2D-Ls in stressed cells.

Patterns of Gastric Injury: Beyond Helicobacter Pylori

Gastric biopsies are routinely obtained from patients with symptoms related to the gastrointestinal tract and, as a result, a variety of histologic changes are observed in patients with or without endoscopic evidence of mucosal injury. Although Helicobacter pylori-related gastritis is still common, several other patterns of mucosal injury are increasingly encountered. These patterns of injury are classified based on the nature and distribution of inflammation, location of epithelial cell injury, presence of crystal or pigment deposition, and/or other unique features. This article discusses each of these patterns and provides a differential diagnosis for each.

Microbes and Viruses Are Bugging the Gut in Celiac Disease. Are They Friends or Foes?

The links between microorganisms/viruses and autoimmunity are complex and multidirectional. A huge number of studies demonstrated the triggering impact of microbes and viruses as the major environmental factors on the autoimmune and inflammatory diseases. However, growing evidences suggest that infectious agents can also play a protective role or even abrogate these processes. This protective crosstalk between microbes/viruses and us might represent a mutual beneficial equilibrium relationship between two cohabiting ecosystems. The protective pathways might involve post-translational modification of proteins, decreased intestinal permeability, Th1 to Th2 immune shift, induction of apoptosis, auto-aggressive cells relocation from the target organ, immunosuppressive extracellular vesicles and down regulation of auto-reactive cells by the microbial derived proteins. Our analysis demonstrates that the interaction of the microorganisms/viruses and celiac disease (CD) is always a set of multidirectional processes. A deeper inquiry into the CD interplay with Herpes viruses and Helicobacter pylori demonstrates that the role of these infections, suggested to be potential CD protectors, is not as controversial as for the other infectious agents. The outcome of these interactions might be due to a balance between these multidirectional processes.

Rare Gastric Lesions Associated with Helicobacter pylori Infection: A Histopathological Review

Helicobacter pylori infection is associated with chronic gastritis, peptic ulcer disease, gastric adenocarcinoma, and mucosa-associated lymphoid tissue lymphoma. However, some rare gastric lesions exhibiting distinctive histological features may also be associated with H. pylori infection, including lymphocytic gastritis, granulomatous gastritis, Russell body gastritis, or crystal-storing histiocytosis. Although diverse factors can contribute to their development, there is convincing evidence that H. pylori infection may play a pathogenic role. These findings are mainly based on studies in patients with these lesions who exhibited clinical and histological improvements after H. pylori eradication therapy. Thus, H. pylori eradication therapy might be indicated in patients with no other underlying disease, particularly in countries with a high prevalence of H. pylori infection. This review describes the characteristic histological features of these rare lesions and evaluates the evidence regarding a causative role for H. pylori infection in their pathogenesis.

Celiac disease and Helicobacter pylori infection in children: Is there any Association?

BACKGROUND AND AIM

Helicobacter pylori (HP) infection can influence the inflammatory and immune responses in the gut and may therefore play a role in the development of gluten-related enteropathy in genetically susceptible individuals. Our objective was to assess the relationship between celiac disease and HP infection in children.

METHODS

Children (1-18 years) diagnosed as celiac disease (CD) (n = 324) with submission of gastric and duodenal biopsies and duodenal histology having Marsh grade III features were eligible for the study. Non-celiac patients referred for endoscopy were selected as controls. We studied proportion of HP prevalence in children with confirmed CD as compared with HP prevalence in reference group comprising non-celiac children referred for endoscopy. We also evaluated predictors of HP infection in children with celiac disease.

RESULTS

Of the 324 participants with CD, gastric HP was seen in 37 (11.4%) patients. The prevalence of HP in patients without CD (50%, P < 0.001) was significantly higher. Among patients with CD, HP infection was most frequent in patients with Marsh IIIa. In the stepwise regression analysis for risk factors of HP infection in CD patients: presence of gastritis, hemoglobin, and absence of scalloping were found to be independent predictors in a multivariate setup.

CONCLUSION

Celiac disease and gastric HP infection have inverse relationship that raises the question whether development of HP infection confers protection against CD.

Over 90% of cases of Microscopic Colitis can be diagnosed by performing a short colonoscopy

AIMS

To determinate the topographical distribution of key diagnostic histological features of lymphocytic colitis (LC) and collagenous colitis (CC) and to establish what correlations may exist between the histological findings and the causes and severity of MC.

PATIENTS AND METHODS

Patients with MC were included in a prospective multicentre French study from September 2010 to October 2012. MC was diagnosed by performing total colonoscopy with multiple biopsies of the rectum and colon collected in separate jars and analyzed separately for each site (descending and sigmoid colon, transverse colon, ascending colon). CC was defined as a subepithelial collagen layer>10μm thick and LC as an intraepithelial lymphocyte (IEL) count>20 lymphocytes per 100 epithelial cells without any associated thickening of the subepithelial collagen.

RESULTS

Ninety-five patients, 69 with LC 26 and with CC, were included in the analysis. The sensitivity of the biopsies for diagnosing MC was maximum in the transverse colon and minimum in the rectum. Rectal and left colonic biopsies resulted in the diagnosis of CC and CL in 93% and 94% of cases, respectively. All the remaining cases of MC were diagnosed by performing additional biopsies beyond the splenic flexure. In patients with LC, a higher rate of IELs was associated with the absence of abdominal pain (P=0.01) and a shorter duration of diarrhea (P=0.001). In patients with CC, a lower level of collagen thickness in the basement membrane was associated with the presence of an autoimmune disease (P=0.02).

CONCLUSION

More than 90% of cases of microscopic colitis were diagnosed in this study by performing rectal and left colonic biopsies.

Propionibacterium acnes overabundance and natural killer group 2 member D system activation in corpus-dominant lymphocytic gastritis

Corpus‐dominant lymphocytic gastritis (LyG) is characterized by CD8⁺ T‐cell infiltration of the stomach epithelium by a so far uncharacterized mechanism. Although Helicobacter pylori is typically undetectable in LyG, patients respond to H. pylori antibiotic eradication therapy, suggesting a non‐H. pylori microbial trigger for the disease. Comparative microbiota analysis of specimens from LyG, H. pylori gastritis and healthy controls precluded involvement of H. pylori in LyG but identified Propionibacterium acnes as a possible disease trigger. In addition, the natural killer group 2 member D (NKG2D) system and the proinflammatory cytokine interleukin (IL)‐15 are significantly upregulated in the gastric mucosa of LyG patients, and gastric epithelial cells respond to microbe‐derived stimuli, including live P. acnes and the microbial products short‐chain fatty acids, with induction of NKG2D ligands. In contrast, H. pylori infection does not activate or even repress NKG2D ligands. Together, our findings identify P. acnes as a possible causative agent for LyG, which is dependent on the NKG2D system and IL‐15 activation. © 2016 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.

Pathological and Clinical Correlation between Celiac Disease and Helicobacter Pylori Infection; a Review of Controversial Reports

There are overwhelming reports and descriptions about celiac associated disorders. Although there is a clear genetic association between celiac disease (CD) and some gastrointestinal disorders, there are controversial reports claiming an association between CD and Helicobacter pylori (H. pylori) infection. Different studies indicated the possible association between lymphocytic gastritis and both CD and H. pylori infection, although this evidence is not consistently accepted. Also it was shown that an increase in intraepithelial lymphocytes count is associated with both H. pylori infection and celiac disease. Therefore the following questions may raise: how far is this infection actually related to CD?, which are the underlying patho-mechanisms for these associations? what are the clinical implications? what is the management? and what would be the role of gluten free diet in treating these conditions? PubMed (PubMed Central), Ovid, ISI of web knowledge, and Google scholar were searched for full text articles published between 1985 and 2015. The associated keywords were used, and papers described particularly the impact of pathological and clinical correlation between CD and H. pylori infection were identified. In this review we tried to answer the above questions and discussed some of the recent developments in the pathological and clinical aspects of CD and H. pylori infection.

Lymphocytic cholecystitis/cholangitis

OBJECTIVES

To describe four cases of an uncommon type of acalculous cholecystitis/cholangitis characterized by increased intraepithelial lymphocytes within the biliary epithelium.

METHODS

Cases were prospectively compiled during regular surgical pathology sign-out. Clinical information was obtained from the electronic medical record and the gross appearance from the surgical pathology reports. Microscopic examination was performed with emphasis on the type, location, and distribution of the inflammatory pattern; presence of intraepithelial lymphocytes (>30 per 100 biliary cells); and presence of metaplasia and epithelial hyperplasia. Immunohistochemical stains for CD3, CD8, and IgG4 were performed in some cases.

RESULTS

All patients were adults who had either biliary pain or obstructive symptoms. All gallbladders had a relatively normal gross appearance and did not contain gallstones or biliary sludge. Microscopic examination showed numerous intraepithelial lymphocytes in the biliary epithelium. The mucosa was frequently expanded by dense inflammatory cell infiltrates. The inflammatory process was more severe in the infundibulum and bile ducts than in the body of the gallbladder. The intraepithelial lymphocytes were CD3+, CD8+. IgG4+ plasma cells were absent.

CONCLUSIONS

The term lymphocytic cholecystitis/cholangitis is proposed. The potential clinical implications and pathogenesis of this inflammatory pattern and the differential diagnosis with other forms of acalculous cholecystitis are discussed.

Chronic gastritis - an update

Helicobacter pylori is the main aetiologic factor for chronic gastritis worldwide. The degree of inflammation and the evolution of this form of chronic gastritis can vary largely depending on bacterial virulence factors, host susceptibility factors and environmental conditions. Autoimmune gastritis is another cause of chronic inflammation in the stomach, which can occur in all age groups. This disease presents typically with vitamin B12 deficiency and pernicious anaemia. The presence of anti-parietal cell antibodies is highly specific for the diagnosis. The role of H. pylori as a trigger for autoimmune gastritis remains uncertain. Other rare conditions for chronic gastritis are chronic inflammatory conditions such as Crohn's disease or on the background of lymphocytic or collagenous gastroenteropathies.

Lymphocytic gastritis is not associated with active Helicobacter pylori infection

BACKGROUND

Lymphocytic gastritis (LG), characterized by marked intra-epithelial lymphocytosis in the gastric mucosa, has been frequently associated with both celiac disease (CD) and H. pylori gastritis. The aim of this study was to review and correlate the morphology of LG with the presence of CD and H. pylori.

MATERIALS AND METHODS

Gastric biopsies diagnosed with LG from 1/1/2006 to 8/1/2013 at our institution and corresponding small bowel biopsies, when available, were reviewed for verification of the diagnosis and to assess for the presence of H. pylori and CD. Immunohistochemical (IHC) staining for H. pylori was performed on all gastric biopsies. Demographic, clinical, and laboratory data were obtained from the medical record.

RESULTS

Fifty-four of the 56 cases that met inclusion criteria demonstrated significant intra-epithelial lymphocytosis as the predominant histologic abnormality; however, none were associated with H. pylori infection by IHC staining. Two cases that also showed a prominent intra-epithelial and lamina propria neutrophilic infiltrate were both positive for H. pylori and were excluded from further study. Of the 36 small bowel biopsies available, 19 (53%) showed changes in CD.

CONCLUSIONS

LG is not a distinct clinicopathologic entity, but a morphologic pattern of gastric injury that can be secondary to a variety of underlying etiologies. When restricted to cases with lymphocytosis alone, LG is strongly associated with CD and not with active H. pylori infection. However, cases that also show significant neutrophilic infiltrate should be regarded as "active chronic gastritis" and are often associated with H. pylori infection. A morphologic diagnosis of LG should prompt clinical and serologic workup to exclude underlying CD.

Helicobacter pylori Associated Lymphocytic Gastritis in a Child

Lymphocytic gastritis (LG) is a rare subtype of chronic gastritis. It is defined as dense proliferation of intraepithelial lymphocytes (IELs) more than 25 lymphocytes per 100 epithelial cells. The known major causes of LG are celiac disease and Helicobacter pylori infection. H. pylori associated LG (HpLG) has more enhanced cytotoxic and apoptotic tendencies than chronic H. pylori gastritis. A 12-year-old girl with postprandial epigastric pain was diagnosed HpLG on endoscopic biopsy. After the 1st eradication therapy, H. pylori bacilli were still found, and urea breathing test was positive. Although the endoscopic finding was partially improved, clinical symptoms and histologic finding were persisted. We could achieve the improvement of clinical symptoms and disappearance of IELs after the 2nd eradication. The discordant of histopathologic and endoscopic improvement occurred after the 1st eradication therapy of HpLG. Therefore the clinical and histopathologic evaluation should be considered as well as endoscopic findings.

Secondary prevention of epidemic gastric cancer in the model of Helicobacter pylori-associated gastritis

Irrespective of its etiology, long-standing, non-self-limiting gastric inflammation (mostly in Helicobacter pylori-associated cases) is the cancerization ground on which epidemic (intestinal-type) gastric carcinoma (GC) can develop. The natural history of invasive gastric adenocarcinoma encompasses gastritis, atrophic mucosal changes, and intraepithelial neoplasia (IEN). The topography, the extent and the severity of the atrophic changes significantly correlate with the risk of developing both IEN and GC. In recent years, both noninvasive (serological) tests and invasive (endoscopy/biopsy) procedures have been proposed to stratify patients according to different classes of GC risk. As a consequence, different patient-tailored GC secondary prevention strategies have been put forward. This review summarizes the histological features of H. pylori-related gastritis and the natural history of the disease. Histological and serological strategies to assess GC risk as well as the clinical management of atrophic gastritis patients are also discussed.

[Gastritis and gastropathy]

Alterations of the stomach mucosa in response to different adverse effects result in various morphological and clinical symptoms. Gastric mucosa alterations can be classified on the bases of diverse viewpoints. It makes this overview difficult, that identical toxic effects may cause different mucosal changes and different toxic agents may produce similar mucosal appearance. The more accurate understanding of the pathological processes which develop in the stomach mucosa needs reconsideration. The authors make an attempt to define gastritis and gastropathy in order to classify and present their features. Gastritis is a histological definition indicating mucosal inflammation. Acute gastritis is caused by infections. The two most important forms of chronic gastritis are metaplastic atrophic gastritis with an autoimmune origin and Helicobacter pylori inflammation. Gastropathy is the name of different structural alterations of the mucosa. Its most important feature is the paucity of inflammatory signs. Gastropathies can be divided into 4 categories based on the nature of the underlying pathological effect, on its morphological appearance and the way of the development. Differential diagnosis is an important pathological and clinical task because different treatment methods and prognosis.

The recognition and classification of lymphoproliferative disorders of the gut

Gastrointestinal lymphomas can be difficult to diagnose, particularly in small samples, when early in development, or when of unusual types. In this review, we describe lymphoid proliferations in the gastrointestinal tract in a location-based manner, including, mouth, esophagus, stomach, small intestine, and large bowel. For the purpose of differential diagnosis, benign mimics of lymphoma are also described. Lymphoma types that are specifically addressed include plasmablastic, extranodal natural killer/T-cell-nasal type, extranodal marginal zone lymphoma (eg, mucosa-associated lymphoid tissue lymphoma), diffuse large B cell, primary follicular of small intestine, enteropathy-associated T cell, and Burkitt and mantle cell. Immunohistochemical markers useful in the diagnostic approach are elaborated in detail.

Decreased risk of celiac disease in patients with Helicobacter pylori colonization

The prevalence of celiac disease (CD) has increased in recent decades without a clear explanation. The "hygiene hypothesis" theorizes that decreased exposure to bacterial antigens may trigger autoimmunity. We aimed to determine whether Helicobacter pylori infection and CD were associated among patients undergoing upper gastrointestinal endoscopy. We performed a cross-sectional study of patients who underwent esophagogastroduodenoscopy with submission of gastric and duodenal biopsies to Miraca Life Sciences, Inc. (Irving, Texas), a US commercial pathology laboratory, during a 4.5-year period (January 2008-June 2012). We compared the prevalence of H. pylori in CD patients with that in persons without CD. We performed multiple logistic regression analysis, adjusting odds ratios for patient age, gender, and racial, ethnic, and socioeconomic factors. Among 136,179 patients, a total of 2,689 (2.0%) had CD. H. pylori prevalence was significantly lower in patients with CD (4.4%) than in those without CD (8.8%; P < 0.0001). After adjustment for the above covariates, this inverse relationship remained strong (adjusted odds ratio (OR) = 0.48, 95% confidence interval (CI): 0.40, 0.58). The relationships were similar in men (unadjusted OR = 0.51, 95% CI: 0.38, 0.69) and women (unadjusted OR = 0.46, 95% CI: 0.36, 0.58) and in all age groups. We conclude that H. pylori presence and CD are inversely associated, a relationship that persists after adjustment for socioeconomic factors. Future studies should address whether H. pylori modulates immune responses to ingested gluten.

Appropriate use of special stains for identifying Helicobacter pylori: Recommendations from the Rodger C. Haggitt Gastrointestinal Pathology Society

Helicobacter pylori is a major cause of gastroduodenal injury, gastric cancer, and lymphoma, and, thus, there is great interest in its detection and eradication. Several detection methods are available, including histochemical and immunohistochemical stains. Application of these stains in clinical practice is heterogenous, to say the least. Although they were developed to enhance H. pylori detection, changing practice models, financial considerations, and a perceived need for rapid case turnaround have led to their widespread use in routine staining studies ordered reflexively on all gastric biopsies. Emerging data suggest that most of these stains are not needed to establish a diagnosis of H. pylori infection, and their added value when biopsies show minimal, or no, inflammation is not clear. In this manuscript, the Rodger C. Haggitt Gastrointestinal Pathology Society puts forth recommendations regarding ancillary stain usage for H. pylori detection based upon critical literature review and collective experience. Pathologists rarely, if ever, detect H. pylori in "normal" biopsies, but readily observe them in optimally stained hematoxylin and eosin sections from infected patients. Therefore, we suggest that use of ancillary stains is appropriate when biopsies show chronic, or chronic active, gastritis without detectable H. pylori in hematoxylin and eosin-stained sections, but performing them "up front" on all gastric biopsies is generally unnecessary. Application of these stains to nongastric biopsies and polyps is appropriate in an extremely limited set of circumstances. It is our hope that recommendations provided herein will provide helpful information to gastroenterologists, pathologists, and others involved in the evaluation of patients for possible H. pylori infection.

High proportion of granzyme B+ intraepithelial lymphocytes contributes to epithelial apoptosis in Helicobacter pylori-associated lymphocytic gastritis

BACKGROUND

Helicobacter pylori infection has been linked to the development of lymphocytic gastritis (LG) characterized by ≥25 intraepithelial lymphocytes (IELs) per 100 epithelial cells. We hypothesize that the changes in the subpopulation and/or cytotoxicity of IELs leading to epithelial cell apoptosis may be involved in the pathogenesis of H. pylori-associated LG.

MATERIALS AND METHODS

We examined IEL subpopulations and the expression of cytotoxic molecules by IELs in biopsy specimens from 36 patients with H. pylori-associated LG by immunostainings for CD3, CD4, CD8, T-cell-restricted intracellular antigen-1 (TIA-1), and granzyme B (GrB) and compared the results with those obtained from 49 patients with H. pylori-associated gastritis (HPG). To investigate whether the IEL-mediated cytotoxicity is related to the increase of epithelial apoptosis, we performed a terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay using ApopTag detection kit.

RESULTS

Between LG and HPG groups, significant differences in the number of CD3+, CD4+, CD8+, TIA-1+ or GrB+ IELs, and ApopTag indices were found. Among the CD3+ IELs, the proportion of CD8+ IELs or TIA-1+ IELs did not differ between two groups. The LG group showed a selective increase in GrB-positive, phenotypically activated IELs, which was paralleled by an increase in ApopTag indices. In contrast, the HPG group showed more heterogeneous IEL subpopulations with more CD4+ IELs and less GrB+ IELs compared with the LG group, and we did not find any significant variable contributing to the epithelial apoptosis in the HPG group.

CONCLUSIONS

This study shows that in addition to the numerical increase in the IELs, there are significant changes in the subpopulations and cytotoxicity of IELs between HPG and H. pylori-associated LG. In particular, enhanced GrB-associated cytotoxicity of the IELs in H. pylori-associated LG contributes to an increase in epithelial apoptosis.

Adherence to the Sydney System guidelines increases the detection of Helicobacter gastritis and intestinal metaplasia in 400738 sets of gastric biopsies

BACKGROUND

The diagnostic yield of individual gastric biopsies and the adherence to the Sydney System guidelines in the United States are unknown.

AIMS

To evaluate the yield of different gastric sampling strategies and determine the adherence to the Sydney System guidelines in a nationwide sample of endoscopists.

METHODS

Using a database of biopsy records diagnosed at a single pathology laboratory, we analysed the results of gastric biopsies taken to evaluate gastric inflammatory conditions in patients with no endoscopic lesions. We then stratified the specimens by site of origin and number of mucosal fragments and calculated the relationship between number and origin of biopsy specimens and detection of Helicobacter pylori and intestinal metaplasia.

RESULTS

Of 400 738 biopsy sets, 66.0% were submitted as antrum; 17.4% as corpus; 2.6% as cardia; and 24.7% without topographic identifiers. Separate containers with at least two antral and two corpus specimens (Sydney System compliant) were available in 15 645 cases (3.9%). For antrum, corpus, and unspecified sites, each additional tissue fragment was associated with an incremental increase in the yield for both H. pylori and intestinal metaplasia. Sydney System-compliant sets had significantly greater yield than most of the unspecified or single-site sets (14.8% and 6.0% respectively). The incisura angularis, rarely sampled, yielded minimal additional diagnostic information.

CONCLUSIONS

In the absence of lesions, the acquisition of at least two biopsy specimens from antrum and corpus, essentially following the Sydney System recommendations, is a sensible strategy that guarantees the maximum diagnostic yield for the most common gastric inflammatory conditions.

Neutrophilic infiltration in gluten-sensitive enteropathy is neither uncommon nor insignificant: assessment of duodenal biopsies from 267 pediatric and adult patients

The histologic findings of celiac disease, that is, gluten-sensitive enteropathy (GSE), are dominated by increased intraepithelial lymphocytes, villous blunting, lymphoplasmacytic infiltration of lamina propria, and crypt hyperplasia. To date, neutrophils have not been thought to constitute a significant cell type in GSE, and their presence often invokes consideration of alternative diagnoses. Thus, we sought to determine the prevalence and severity of neutrophilic infiltration in duodenal biopsies from patients with GSE. The degree of neutrophilic infiltration and features characteristic of GSE were assessed in duodenal biopsies from 267 clinically confirmed GSE patients (116 adults and 151 children). These specimens were graded by the disease activity score (DAS) and the neutrophilic activity score (NAS). Gastric antral biopsies obtained from 195 patients were also evaluated for lymphocytic gastritis. NAS was correlated with DAS and other clinicopathologic features. We found that 56% of pediatric and 28% of adult GSE patients had significant duodenal neutrophilia. NAS was higher in children than in adults (2.3 vs. 1.2, P<0.001). Multivariate regression showed that DAS, eosinophilic infiltration, and foveolar metaplasia correlated positively, and age correlated negatively with NAS. Lymphocytic gastritis was seen in 21.5% of the gastric biopsies. The presence of lymphocytic gastritis correlated positively with NAS and DAS, and in the pediatric population it correlated negatively with age. Significant duodenal neutrophilia is often found in patients with celiac disease, especially in the pediatric population, and is associated with more active disease. Thus, the findings of duodenal neutrophilia in biopsies, otherwise consistent with GSE, should not preclude the diagnosis of GSE.

Gastrointestinal pathology in celiac disease: a case series of 150 consecutive newly diagnosed patients

The main histologic feature of celiac disease is increased intraepithelial lymphocytes (IELs) with or without villous atrophy of the duodenal mucosa. The aim of this study was to document a broad range of additional morphologic changes in intestinal mucosa biopsy specimens from patients with celiac disease. Our cohort comprised 150 patients with positive tissue transglutaminase serologic findings; 7 were at Corazza stage A1, 58 at stage B1, and 85 at stage B2. IEL counts per 100 epithelial cells ranged from 34 to 156 (mean, 88.6); a significant neutrophilic infiltrate was present in 85 cases (56.7%); eosinophil count ranged from 3 to 50 per high-power field (mean, 14.6). Additional findings included morphologic changes in enterocytes in 68.7%, subepithelial collagen thickening in 45.3%, and associated lymphocytic gastritis in 30.4% of patients. We demonstrated that these underrecognized features, which can be misleading, are not uncommon in celiac disease and were positively associated with more advanced stages of the disease (P < .0001).

Clinical and histological presentation of Helicobacter pylori and gluten related gastroenteropathy

BACKGROUND

Celiac disease has been reported to be associated with gastric abnormalities. The aim of this study was to assess the relationship between the prevalence of celiac disease and Helicobacter pylori infection in an Iranian population of 250 patients.

METHODS

Biopsies were taken from the gastric antrum and duodenum. Morphology and histology were evaluated using the updated Sydney system and modified Marsh criteria, respectively. To simplify the interpretation of gastric lesions we classified gastritis in macroscopic and microscopic stages. Serology for anti-tissue transglutaminase antibody was performed to determine the presence of celiac disease.

RESULTS

Among 250 patients, 232 (93%) had histological evidence of Helicobacter pylori infection. Histological abnormalities (Marsh I to IIIc) were present in 24 (10%). Of 24 patients, 20 (83%) with histological abnormalities were infected with Helicobacter pylori. Of 250 patients, 25 (10%) had a positive anti-tissue transglutaminase antibody. Of 25 anti-tissue transglutaminase antibody positive patients, 9 (3.6%) had microscopic and macroscopic enteritis (Marsh I to IIIc).

CONCLUSIONS

Clinical presentation of celiac disease was not distinguishable from cases infected with Helicobacter pylori. Histology, even in patients with positive serology, was non-specific and unhelpful. We found a high prevalence of Helicobacter pylori infection and chronic gastritis, but neither was associated with celiac disease, in agreement with studies in Western populations.

Lymphocytic gastritis in pediatric celiac disease

An increase in gastric intraepithelial lymphocytes has been observed in some patients with the typical small intestinal changes of celiac disease. To date, no clinical parameters have been described that identify the subset of patients more likely to have gastric involvement. In this study we compared the clinical features of celiac disease patients with and without lymphocytic gastritis to determine if the presence of gastric involvement at diagnosis portends a more severe form of celiac disease. We reviewed the pathology reports and hematoxylin and eosin-stained slides of 304 patients with biopsy-proven celiac disease diagnosed over an 11-year period. Thirty-nine of these patients had lymphocytic gastritis. Compared to patients without gastric involvement, those with lymphocytic gastritis were statistically more likely to be diagnosed at an earlier age and present with more profound laboratory findings and duodenal mucosal damage compared to patients with celiac disease without gastric involvement. These findings indicate that in the pediatric population, the presence of lymphocytic gastritis in celiac disease defines a unique group of patients with more severe disease (by clinical and laboratory measures) at the time of diagnosis.

[Histopathology of coeliac disease]

Coeliac disease is a common disease, affecting 1% of the population. Clinical manifestations are multiple. The diagnosis requires serologic testing and a duodenal biopsy that shows the characteristic findings of intraepithelial lymphocytosis, crypt hyperplasia and villous atrophy, and a positive response to a gluten-free diet. In most patients, the histological diagnosis is easily established. Pitfalls in the pathological diagnosis include a poorly orientated biopsy specimen, either an inadequate biopsy sampling in patients with patchy villous atrophy and the other causes of villous atrophy. A non-response to the gluten-free diet needs to reassess first, the initial diagnosis, second to be sure of the gluten-free diet adherence, and third, to exclude malignant complications such as refractory celiac disease or enteropathy-associated T-cell lymphoma.

Gastroduodenal mucosa in microscopic colitis

BACKGROUND

We have assessed gastroduodenal, endoscopical and histopathological findings in a series of patients with microscopic colitis (MC).

METHODS

We studied 75 patients with MC, 27 with collagenous colitis (CC) and 48 with lymphocytic colitis (LC), and 60 controls. Data of endoscopical findings were collected and biopsies were assessed.

RESULTS

Helicobacter pylori infection rate was 15% in MC and 28% in the controls (p = 0.088). Age at diagnosis of MC was higher in H. pylori positive than negative patients (63.4 ± 9.6 vs. 54.4 ± 13.1 years; p = 0.034). Gastric endoscopic erosions were more prevalent in CC than in LC (25.9% vs. 6.2%; p = 0.030) and associated with thick body glands and antral predominance of gastritis in H. pylori positive patients. Rates of focal gastritis (5.6% vs. 6.9%) and lymphocytic gastritis (5.6% vs. 10%) were similar in MC and controls. LC was associated with gastric epithelial lymphocytosis and lymphocytic gastritis. Fifteen patients (20%) had celiac disease.

CONCLUSIONS

Unlike LC, CC is associated with endoscopic erosions, likely related with the high acid secretion capacity as indicated by the ample body glands and antral predominance of gastritis in H. pylori associated cases of CC. The presence of some divergent gastroduodenal features in LC and CC, and in comparison with those reported in inflammatory bowel disease (IBD), supports the concept that these two conditions differ not only from IBD but also from each other. The findings also suggest the presence of pathogenetic links between colorectal and gastroduodenal abnormalities.

An update in the diagnosis of coeliac disease

Coeliac disease is increasing in prevalence, which is currently estimated at one in 100 of the population and may occur de novo in adults. The diagnosis requires a joint clinicopathological approach; the recommended first-line test is serology with immunoglobulin A (IgA) tissue transglutaminase and IgA endomysial antibodies. These serological tests show high levels of sensitivity and specificity, but biopsy is the gold standard to confirm the diagnosis. It is important that both tests are performed before the introduction of a gluten-free diet. Although the classical histopathology changes of coeliac disease with partial or total villous atrophy are well recognized, the pathology classification of coeliac disease is changing, with recognition that coeliac disease may show minimal pathology (normal architecture and an intraepithelial lymphocyte count/100 enterocytes ≥ 25). This entity is also described as lymphocytic duodenosis, and recommendation of follow-up serology testing is paramount in this condition. Follow-up of patients with coeliac disease is warranted, as normal serology does not predict mucosal recovery. Failure to heal predicts risk of progression to refractory coeliac disease and malignancies. Refractory coeliac disease occurs in 1-2% of patients and this diagnosis requires a combined clinical and histopathology approach with immunocytochemistry.

Clinicopathological characteristics of primary gastric T-cell lymphoma

AIMS

To investigate the clinicopathological characteristics of 20 primary gastric T-cell lymphoma (GTCL) cases without human T-lymphotropic virus type I infection in Japan, a non-endemic area for coeliac disease.

METHODS AND RESULTS

Fifteen cases had no history of persistent diarrhoea or severe hypoproteinaemia. Histologically, 13 cases (65%) consisted of large cell lymphoma and seven (35%) were of medium-sized cells. Intraepithelial lymphoma cell invasion was found in three cases (15%). Two of 10 surgical cases (20%) showed intramucosal tumour cell spreading with enteropathy-like features. Helicobacter pylori CagA gene was detected in three of 10 cases (30%). The lymphoma cells of all 20 cases were positive for CD3 and/or TCRbetaF1 and negative for CD56. CD4- and CD8- lymphoma was found in 11 cases (55%), CD4+ lymphoma in seven (35%) and CD8+ lymphoma in two (10%). CD30+, CD5+ and CD25+ lymphomas were detected in nine (45%), 10 (50%) and 11 (55%) cases, respectively. Five-year survival of the 16 available cases was 54%. Early clinical stage and medium-sized cell lymphoma were significantly (P < 0.05) better prognostic factors.

CONCLUSIONS

Patients with GTCL exhibit distinct clinicopathological findings and prognoses from those with enteropathy-associated T-cell lymphomas. GTCL may be mainly derived from lamina propria and parafollicular T cells.

Pathology of non-Helicobacter pylori gastritis: extending the histopathologic horizons

The development of modern endoscopic techniques, easier and greater access to healthcare, and interest in Helicobacter pylori infection and its implications have all led to a significant increase in upper endoscopies. In turn, gastroenterologists and pathologists have been recognizing an ever-increasing number of patterns of mucosal injury. Consequently, there is now an interest in a wider aspect of non-neoplastic gastric pathology, namely, non-HP (H. pylori) gastritis. In this review, we present major clinico-pathological entities, based on either the salient morphological features or the underlying etiologies.

Gastric stromal tumors in Carney triad are different clinically, pathologically, and behaviorally from sporadic gastric gastrointestinal stromal tumors: findings in 104 cases

Carney triad, as originally described in 1977, was the association of 3 tumors: gastric epithelioid leiomyosarcoma [later renamed gastrointestinal stromal tumor (GIST)], extra-adrenal paraganglioma, and pulmonary chondroma. The disorder affected mostly young women and was not familial. We studied the clinical and pathologic features of the gastric neoplasm in 104 patients with the syndrome. Most (88%) were young women (mean age, 22 y), and the usual presentation was gastric bleeding. The tumors, commonly antral-based (61%), were multifocal, and ranged from 0.2 to 18.0 cm in dimension. Most (86%) featured round and polygonal (epithelioid) cells. Metastasis occurred in 49 patients (47%): to gastric lymph nodes (29%), liver (25%), and peritoneum (13%). Immunopositivity was detected in the tumors tested as follows: KIT, 100%; CD34, 75%; PKCtheta, 21%; PDGFRA, 90%; and smooth muscle actin, 6%. Fourteen patients (13%) died of metastatic GIST at a mean age of 45 years (range, 30 to 69 y). Estimated 10 and 40-year survivals were 100% and 73%, respectively. Median survival time was 26.5 years (range, 16 to 60 y). There was no correlation between the National Institutes of Health tumor risk classification and the tumor behavior. Compared with sporadic gastric GISTs, the gastric stromal tumor in Carney triad showed distinctive features: female predilection, young patient age, epithelioid cell predominance, multifocality, frequent lymph node metastasis, serial tumor occurrence, and unpredictable behavior. Thus, the Carney triad gastric stromal tumor is different clinically, pathologically, and behaviorally from sporadic gastric GIST.

Lymphocytic disorders of the gastrointestinal tract: a review for the practicing pathologist

Increased numbers of intraepithelial lymphocytes (lymphocytosis) can be found in the esophagus, stomach, small intestine, and colon in a variety of clinical circumstances. This review, directed at practicing pathologists, portrays the normal resident lymphocyte population in the mucosa of each segment of the digestive tract and discusses the different situations that may result in quantitative or qualitative alterations of intraepithelial lymphocytes. Esophageal lymphocytosis has not been fully characterized and its clinical significance, if any, awaits definition. Thus, this diagnosis is presently discouraged. In the stomach, it is particularly important to exclude Helicobacter pylori infection and celiac sprue before diagnosing lymphocytic gastritis. Duodenal lymphocytic infiltrates, inextricably tied with alterations of the villous architecture of the mucosa, are often caused by gluten sensitivity. However, similar morphologic changes may be caused by a vast array of other conditions that must be carefully considered and excluded. Lymphocytic and collagenous colitis are most often unexplained, but their frequent association with autoimmune conditions or certain medications deserve a thorough investigation in each case. Using a combination of histologic and clinical clues, a cause for the intraepithelial lymphocytic infiltration can be identified in many instances. As some of the associated conditions are amenable to effective treatment, the importance of diligently seeking such associations before resorting to a diagnosis of primary lymphocytosis is emphasized.

Collagenous gastritis: histopathologic features and association with other gastrointestinal diseases

Collagenous gastritis (CG) characterized by the deposition of a subepithelial collagen band and accompanying inflammatory infiltrate is a rare disorder. The natural history and pathogenesis of CG remain unclear. We describe the histologic features (23 gastric, 18 duodenal, and 4 colonic biopsies) and clinical findings of an additional 12 cases. Histologic features including active or chronic inflammation, surface epithelial injury, intraepithelial lymphocytosis, intestinal metaplasia, and Helicobacter pylori, and measurement of thickness of subepithelial collagenous band were evaluated in gastric biopsies. The clinical features, endoscopic findings, and follow-up were obtained and correlated with histologic features. There was an even number of males (n=6) and females (n=6). Four patients were children/young adults, 3 of whom (75%) presented with anemia and gastric nodularity. Eight patients were adults, 6 of whom (75%) had an associated autoimmune disease (1 with Hashimoto thyroiditis and polymyositis) or other intestinal disease (3 with celiac sprue, 1 with collagenous colitis, 1 with collagenous sprue), in contrast to none in the 4 children/young adults, P=0.06. The range of subepithelial collagen thickness was 15 to 120 microm in CG. The collagenous layer showed surface epithelial injury and entrapped inflammatory cells. On presentation, the thickened collagen distribution in the antrum and body was variably patchy and diffuse. Four (33%) patients showed lymphocytic gastritis (3 within the same biopsy); one of these patients also had celiac sprue and another had collagenous sprue. Three (25%) patients had celiac sprue (2 had duodenal biopsy proven and 1 had a clinical diagnosis of celiac sprue). An additional patient had duodenal biopsies showing collagenous sprue. Four patients had follow-up biopsies during a 3 to 119-month period after the diagnosis of CG. CG persisted on the follow-up gastric biopsies in 3 (75%) of the 4 patients, and the other patient had lymphocytic gastritis, a finding not seen in previous biopsies. CG is a rare disorder with a distinct presentation and association in pediatric and adult patients. An absence of associated intestinal and autoimmune diseases characterizes the pediatric population. Association with lymphocytic gastritis, celiac or collagenous sprue, collagenous colitis, and autoimmune disorders are frequently seen in adult patients.

Optimal approach to obtaining mucosal biopsies for assessment of inflammatory disorders of the gastrointestinal tract

Endoscopic evaluation and mucosal biopsy analysis have assumed important roles in the clinical management of patients with symptoms related to the gastrointestinal tract. Several common inflammatory diseases, including eosinophilic esophagitis, Barrett's esophagus, Helicobacter pylori infection, celiac disease, lymphocytic colitis, collagenous colitis, and inflammatory bowel disease, may display a patchy or discontinuous distribution and, thus, multiple mucosal samples may be required to obtain diagnostic tissue in some cases. Not surprisingly, clinicians and pathologists are increasingly challenged to determine the optimum number of procedures and tissue samples necessary to detect, or exclude, the presence of inflammatory disorders of the gastrointestinal tract. Unfortunately, clinical practice varies widely with respect to tissue sample procurement in the evaluation of these disorders, particularly when the endoscopic appearance of the gastrointestinal mucosa is normal or shows only minimal changes. Guidelines concerning the appropriate number of tissue samples are well established for some diseases, such as Barrett's esophagus and chronic gastritis, but are not clear in other instances. The purpose of this review is to discuss the available literature pertaining to appropriate endoscopic sampling in the assessment of medical diseases of the gastrointestinal tract, and to develop recommendations regarding the clinical evaluation of common gastrointestinal disorders.