cliot (version 1.0.0)

montreal_ibd_classification: Montreal Classification for Inflammatory Bowel Disease

Description

Generates the Montreal Classification code for Crohn's Disease (CD) or Ulcerative Colitis (UC). For CD, it classifies based on Age at diagnosis (A), Location (L), and Behavior (B). For UC, it classifies based on Extent (E) and Severity (S).

Usage

montreal_ibd_classification(disease_type, age_years = NULL, cd_location = NULL,
                            cd_behavior = NULL, cd_upper_gi = 0, cd_perianal = 0,
                            uc_extent = NULL, uc_severity = NULL)

Value

A list containing:

Classification_Code

The resulting Montreal classification string (e.g., "A2 L1 B1" or "E2 S1").

Arguments

disease_type

String. "crohns" or "uc".

age_years

Numeric. Age at diagnosis (Required for Crohn's). A1: <17, A2: 17-40, A3: >40.

cd_location

String. Disease location (Crohn's). "ileal" (L1), "colonic" (L2), "ileocolonic" (L3).

cd_behavior

String. Disease behavior (Crohn's). "non_stricturing_non_penetrating" (B1), "stricturing" (B2), "penetrating" (B3).

cd_upper_gi

Numeric (0 or 1). Involvement of upper GI tract (L4 modifier). (1 = Yes).

cd_perianal

Numeric (0 or 1). Perianal disease modifier (p). (1 = Yes).

uc_extent

String. Extent of disease (UC). "proctitis" (E1), "left_sided" (E2), "extensive" (E3).

uc_severity

String. Disease severity (UC). "remission" (S0), "mild" (S1), "moderate" (S2), "severe" (S3).

References

Satsangi J, Silverberg MS, Vermeire S, Colombel JF. The Montreal classification of inflammatory bowel disease: controversies, consensus, and implications. Gut. 2006;55(6):749-753. doi:10.1136/gut.2005.082909

Examples

# Example 1: Crohn's Disease
# 25yo, Ileal, Stricturing, No upper/perianal
montreal_ibd_classification("crohns", 25, "ileal", "stricturing", 0, 0)

# Example 2: Crohn's with modifiers
# 16yo, Colonic, Penetrating, Perianal disease present
montreal_ibd_classification("crohns", 16, "colonic", "penetrating", 0, 1)

# Example 3: Ulcerative Colitis
# Left-sided, Moderate severity
montreal_ibd_classification("uc", uc_extent = "left_sided", uc_severity = "moderate")