Normal:
(1) epithelium: normal
(2) inflammatory cells: small numbers of lymphocytes, plasma cells, macrophages and mast cells in the lamina propria
(3) other findings: minimal interstitial edema
Grade 1:
(1) epithelium: no significant epithelial changes
(2) inflammatory cells: increased numbers of chronic inflammatory cells in the lamina propria, with occasional foci of polymorphonuclear leukocytes
(3) other findings: minimal to mild interstitial edema
Grade 2:
(1) epithelium: mild regenerative change, with Paneth cells in the crypts
(2) inflammatory cells: severe chronic inflammation in the lamina propria, with polymorphonuclear leukocytes present within crypts and ducts
(3) other findings: fibrosis may be present
Grade 3:
(1) epithelium: marked regenerative changes, sometimes with areas of ulceration
(2) inflammatory cells: severe inflammation with crypt abscesses
(3) other findings: occasional multinucleated giant cells in the lamina propria
