Components

 intestinal villi

• intestinal surface epithelium
• intestinal villi lamina propria

 intestinal crypts
 intestinal lamina propria
 intestinal muscularis mucosae

Lesions

 architectural anomalies

• intestinal villous atrophy
  • hyperplastic intestinal villous atrophy (increased crypt depth)
  • hypoplastic intestinal villous atrophy (decreased crypt depth)

 surface epithelium anomalies

• enterocyte anomalies
  • enterocyte shape
  • enterocyte brush border (presence/absence)
  • tufted superficial cells
  • syncitial enterocytes
  • stainable iron enterocytes
  • vacuolated enterocytes (epithelial vacuolization)
  • enterocytes macrocytosis

• intraepithelial lymphocytes increase
• intraepithelial granulocytes
• microulcerations

 intestinal crypts anomalies

• intestinal crypt hyperplasia
• intestinal crypt abcesses
• intestinal focal crypt necrosis
• Paneth cell anomalies
  • Paneth cell hyperplasia
  • Paneth cell absence
  • Paneth cell morphologic anomalies

• intestinal endocrine cells hyperplasia
• intestinal endocrine cells absence

 intestinal lamina propria anomalies

• intestinal cellular infiltration
  • intestinal neutrophilic
  • intestinal eosinophilic
  • intestinal lymphocytic
  • intestinal plasmacytic
  • intestinal histiocytic
    • intestinal PAS-positive histiocytic
    • intestinal atypical histiocytic

• intestinal lymphoid depletion (intestinal plasmacytic depletion)
• intestinal abscesses
• intestinal granulomas
• intestinal follicular lymphoid hyperplasia
• intestinal lymphangiectasia
• dense collagen band beneath the intestinal surface epithelium
• intestinal amorphous eosinophilic deposition
• intestinal amyloid deposition (intestinal amyloidosis)