Intraepithelial lymphocytes, scores, mimickers and challenges in diagnosing gluten-sensitive enteropathy (celiac disease)

Table 1 Revised Updated Marsh-Oberhuber classification of gluten-sensitive enteropathy (5 states of submucosal injury 0-4)

Type 0

Pre-infiltrative: normal V:C ratio and crypts with < 20-25 IELs per 100 enterocytes (1:5 or 1:4)

Type 1

Infiltrative type: normal V:C ratio and crypts, but ↑ IELs (≥ 20-25 IELs/100 enterocytes)

Type 2

Infiltrative-hyperplastic type: normal V:C ratio, but crypt hyperplasia with ↑ IELs

Type 3

Destructive (flat mucosa) type of GSE lesion according to the degree of villous atrophy

Type 3a: mild villous atrophy with V: C < 3:1, and ↑ IELs

Type 3b: marked villous atrophy with V: C < 1:1, and ↑ IELs

Type 3c: total villous atrophy with completely flat mucosa and ↑ IELs

Type 4

Atrophic type (hypoplastic); flat mucosa with only a few crypts and near-normal IEL count

V:C: Villous to crypt ratio (normal, V:C > 3:1); GSE: Gluten-sensitive enteropathy; IEL: Intraepithelial lymphocytes. The upper limit of IEL may be considered 20 or 25 according to the country, institution, and physician’s preference, although mostly 25 seems to be the most accepted current threshold.