Diagnostic clues in patients with clinical malabsorption and pathological small intestinal villous atrophy: Immune-mediated type and beyond

Table 2 Pathological classification of autoimmune enteropathy[49]

Classification	Active chronic duodenitis	CeD-like	GVHD-like	Mixed/no predominant
Description[49]	Villous atrophy, expansion of the lamina propria by mixed but predominantly mononuclear inflammation (consisting of lymphocytes, plasma cells, and eosinophils), and neutrophilic cryptitis (with or without crypt abscesses); with or without increased apoptosis in the crypt epithelium. Plasma cells were the predominant cell within the lamina propria inflammatory infiltrate	Villous atrophy and marked IEL (> 40 lymphocytes/100 enterocytes)	Increased apoptosis in crypt epithelium (> 1 apoptotic figure per 10 crypts), with or without crypt dropout, with minimal inflammation	Admixture of ≥ 2 patterns or insufficient features to qualify for other patterns

CeD: Celiac disease; GVHD-like: Graft-vs-host disease-like; IEL: Intraepithelial lymphocyte.