Representation of the categories for location of intestinal disease used in the Paris classification of IBD in children, a modification of the Montreal classification used for adults. Upper GI disease (L4a/L4b) may coexist with lower GI disease (L1, L2 or L3). Disease location is based on macroscopic appearance of mucosal ulceration at endoscopy or bowel wall thickening on radiography. The presence of mucosal erythema and/or granularity is not sufficient to be considered evidence of involvement. The Paris classification also incorporates categories for patient age, growth effects, and disease behavior (stricturing, penetrating, or neither).
Data from: Levine A, Griffiths A, Markowitz J et al. Pediatric modification of the Montreal classification for inflammatory bowel disease: The Paris classification. Inflamm Bowel Dis 2011; 17:1314.
