Definition/General

Introduction:
-Lymphocytic gastritis is a rare form of chronic gastritis characterized by increased intraepithelial lymphocytes
-It is defined by >20 lymphocytes per 100 epithelial cells
-It may be associated with celiac disease and other autoimmune conditions
-It represents a distinct histological pattern.
Origin:
-Results from immune-mediated inflammation
-Associated with gluten sensitivity in some cases
-May represent hypersensitivity reaction to dietary or environmental antigens
-T-cell mediated inflammatory response
-Exact pathogenesis incompletely understood.
Classification:
-Primary lymphocytic gastritis: idiopathic
-Secondary forms: associated with celiac disease (40-50% cases)
-Associated with H
-pylori infection
-Drug-induced (NSAIDs, PPIs)
-Associated with autoimmune conditions.
Epidemiology:
-Rare condition (<1% of gastritis cases)
-Female predominance (2:1 ratio)
-Middle-aged adults (40-60 years)
-Strong association with celiac disease (40-50%)
-Higher prevalence in Northern Europe.

Clinical Features

Presentation:
-Dyspepsia (most common symptom)
-Epigastric pain and discomfort
-Malabsorption symptoms (celiac disease)
-Diarrhea and weight loss
-Iron deficiency anemia
-Symptoms of associated autoimmune diseases.
Symptoms:
-Abdominal pain (epigastric)
-Dyspepsia and indigestion
-Diarrhea (if celiac disease)
-Weight loss and malnutrition
-Fatigue and weakness
-Dermatitis herpetiformis (celiac association).
Risk Factors:
-Celiac disease (major association)
-Gluten sensitivity
-Family history of autoimmune diseases
-Other autoimmune conditions: thyroid disease, diabetes
-H
-pylori infection
-NSAID use.
Screening:
-Upper endoscopy with biopsy
-Celiac serology: anti-tTG, anti-EMA
-HLA typing (DQ2/DQ8)
-H
-pylori testing
-Gluten-free diet trial
-Small bowel biopsy (celiac disease).

Master Lymphocytic Gastritis Pathology with RxDx

Access 100+ pathology videos and expert guidance with the RxDx app

Gross Description

Appearance:
-Varioliform gastritis (characteristic endoscopic pattern)
-Aphthous-like erosions
-Mucosal nodularity and irregularity
-Cobblestone appearance
-Erythematous and friable mucosa
-Normal appearance possible.
Characteristics:
-Antral involvement most common
-Diffuse mucosal changes
-Multiple small erosions
-Thickened folds possible
-Nodular gastritis pattern
-May appear normal endoscopically.
Size Location:
-Antral predominance (60-70% cases)
-May involve corpus and fundus
-Diffuse distribution possible
-Concurrent duodenal changes (celiac disease)
-Patchy involvement.
Multifocality:
-Multifocal distribution
-Often pan-gastric involvement
-Associated with duodenal changes (celiac disease)
-Variable endoscopic appearance
-Skip lesions possible.

Microscopic Description

Histological Features:
-Increased intraepithelial lymphocytes (>20/100 epithelial cells)
-Chronic inflammation in lamina propria
-Surface epithelial damage and regeneration
-Lymphoid follicles may be present
-Minimal glandular atrophy initially.
Cellular Characteristics:
-Intraepithelial T-lymphocytes (predominantly CD8+)
-Surface epithelial damage
-Chronic inflammatory infiltrate in lamina propria
-Lymphocytes and plasma cells
-Increased mitotic activity.
Architectural Patterns:
-Preserved glandular architecture (early stages)
-Surface epithelial irregularity
-Foveolar hyperplasia
-Lamina propria expansion
-Progressive atrophy (chronic cases)
-Intestinal metaplasia (late changes).
Grading Criteria:
-Intraepithelial lymphocyte count: >20/100 epithelial cells (diagnostic)
-Surface epithelial damage: mild, moderate, severe
-Chronic inflammation grade: 0-3
-Atrophy assessment: 0-3.

Immunohistochemistry

Positive Markers:
-CD3 (T-lymphocytes)
-CD8 (cytotoxic T-cells predominant)
-CD20 (B-cell component)
-Ki-67 (increased proliferation)
-CD68 (macrophages)
-CD117 (mast cells).
Negative Markers:
-CD4 (fewer helper T-cells)
-Chromogranin A (normal neuroendocrine cells)
-H
-pylori (may be absent)
-Viral markers (CMV, EBV) typically negative.
Diagnostic Utility:
-Confirms T-cell nature of intraepithelial lymphocytes
-Demonstrates CD8+ predominance
-Excludes lymphoproliferative disorders
-Assesses inflammatory pattern
-Evaluates for viral infections.
Molecular Subtypes:
-CD8+ T-cell predominant pattern
-Mixed CD4+/CD8+ pattern
-Associated with celiac disease: similar IEL pattern
-H
-pylori-associated: mixed inflammatory pattern.

Molecular/Genetic

Genetic Mutations:
-HLA-DQ2/DQ8 association (celiac-related cases)
-CTLA-4 polymorphisms
-IL-15 gene variants
-TNF-α gene polymorphisms
-T-cell receptor gene rearrangements.
Molecular Markers:
-Elevated IL-15
-Increased interferon-γ
-T-cell activation markers
-Tissue transglutaminase (celiac association)
-Zonulin elevation (intestinal permeability).
Prognostic Significance:
-Celiac association: responds to gluten-free diet
-Idiopathic cases: variable response to treatment
-H
-pylori association: responds to eradication
-Chronic inflammation: risk of atrophy.
Therapeutic Targets:
-Gluten-free diet (celiac-associated cases)
-H
-pylori eradication (when present)
-Corticosteroids (severe cases)
-Proton pump inhibitors
-Elimination diets (food sensitivities).

Differential Diagnosis

Similar Entities:
-H
-pylori gastritis
-Autoimmune gastritis
-Reactive gastropathy
-Viral gastritis (CMV, EBV)
-Primary gastric lymphoma
-Crohn disease.
Distinguishing Features:
-Lymphocytic gastritis: increased IEL >20/100, CD8+ predominance
-H
-pylori: organisms present, neutrophilic activity
-Autoimmune: corpus involvement, ECL hyperplasia
-Viral: inclusion bodies
-Lymphoma: monoclonality.
Diagnostic Challenges:
-Accurate IEL counting
-Distinguishing from reactive changes
-Identifying underlying associations
-Correlation with celiac serology
-Excluding viral infections
-Assessment of treatment response.
Rare Variants:
-Pediatric lymphocytic gastritis
-Drug-induced forms
-Association with tropical sprue
-Concurrent with duodenal lymphocytosis
-Progression to MALT lymphoma.

Sample Pathology Report

Template Format

Sample Pathology Report

Complete Report: This is an example of how the final pathology report should be structured for this condition.

Specimen Information

Gastric biopsy from [site], [number] fragments

Diagnosis

Lymphocytic gastritis

Intraepithelial Lymphocytes

IEL count: [number]/100 epithelial cells (normal <20/100)

Histological Features

Increased intraepithelial lymphocytes with surface epithelial damage and chronic inflammation

Inflammation

Chronic inflammation: [grade], predominantly lymphoplasmacytic

Architecture

Glandular architecture: [preserved/altered]

Special Studies

CD3: [result], CD8: [result]

H. pylori: [present/absent]

[other study]: [result]

Recommendations

Consider celiac disease evaluation, H. pylori testing

Final Diagnosis

Lymphocytic gastritis with increased intraepithelial lymphocytes