Collagenous Gastritis

Definition

Gastric disorder characterized by a thick collagen layer below the surface basement membrane

Irregular, thickened collagen layer below the luminal basement membrane
- Envelops capillaries and inflammatory cells
- Ragged interface with lamina propria
- Average thickness 30-40 microns
- Range 15-129 microns
- Trichrome stain is useful for demonstration of the layer
Lamina propria inflammatory infiltrate
- Predominantly lymphocytes and plasma cells
- Fewer neutrophils and eosinophils
Intraepithelial lymphocytes variable
- From normal to 61/100 enterocytes
Luminal surface epithelium flattened, may detach
- Glandular atrophy
Involves antrum and/or body
- May be patchy or diffuse
Associated lymphocytic gastritis in 33% of cases
- May be seen at all ages
Adult and pediatric cases may differ in presentation and association with other GI or autoimmune diseases, see Clinical link at left

Robert V Rouse MD
Department of Pathology
Stanford University School of Medicine
Stanford CA 94305-5342