Montreal classification of inflammatory bowel disease
Updates to Article Attributes
Introduction
Montreal Classification of Inflammatory Bowelinflammatory bowel disease is used primarily to classify the severity of ulcerative colitis and Crohn's disease based on specific categories. This can then be used to guide treatment, discern risk of complications as well as facilitate epidemiological studies 1. There have been different classifications throughout the years, which have been revised to better capture the dynamic nature of inflammatory bowel disease.
History and etymology
The Rome classification in 1991 proposed by the International Working Party suggested a classification system based on disease extent, anatomical location, behaviour and operative history 2,3. This was subsequently revised in Vienna at the World Congress of Gastroenterology in 1998, which introduced age of onset as well as including anatomical location and disease behaviour3.
This was further refined in 2005 to be what the Montreal classification is today. The modifications made in the Crohn's disease section included addition of an age group for <16 years, which allows classification for paediatric cases. It also further defines location and behaviour as it was found that upper gastrointestinal cases and perianal disease were not mutually exclusive and could exist in conjunction with other locations and disease behaviours 1,4. Ulcerative colitis did not have specific sub-classifications listed in the Vienna and Rome classifications, which was introduced with the Montreal classification system. The existing limitation regarding these classifications is that it captures a snap-shot of the disease state as opposed to longitudinally, which is important given the dynamic nature of inflammatory bowel disease 1.
Usage
The Montreal classification system's utility in Crohn's disease lies mostly in epidemiological studies to classify the type of Crohn's disease an individual is afflicted with. Clinically, it allows stratification of individuals with regard to their risk of disease progression and complications. Severity for treatment purposes is primarily based on the Crohn's Disease Activity Index - which identifies disease activity based on a point system - as well as biochemical testing 5,6.
With regard to ulcerative colitis, its classification can be used to determine severity of disease which can be then used to guide treatment.
Classification system
Crohn's disease
-
age of onset:
A1 - ≤16 years
A2 - 17-40 years
A3 - > 40 years
-
location
L1 -
Terminalterminal ileumL2 -
ColoncolonL3 -
Ileocolonileocolon-
L4 -
Upperupper gastrointestinalL4 is a modifier that can be added to L1,2 and L3 when concomitant upper gastrointestinal disease is present
-
behaviour
B1 -
Noncon-stricturing, non-penetratingB2 -
StricturingstricturingB3 -
Penetratingpenetrating-
P -
PerianalperianalP is a modifier that can be added to B1,2 and 3 when concomitant perianal disease is present
Ulcerative colitis
-
extent:
E1 -
Ulcerativeclcerative proctitis; involvement limited to rectum (rectosigmoid junction)E2 -
Leftleft sided ulcerative colitis: involvement limited to portion of colorectum distal to splenic flexureE3 -
Extensiveextensive ulcerative colitis: involvement extends proximal to splenic flexure, 'Pancolitis'
-
severity
S0 -
Ulcerativeulcerative colitis in clinical remission; no symptoms of UCS1 -
Mildmild UC ≤ 4 bloody stools daily, lack of fever, pulse <90 bpm, haemoglobin >105g/L, Erythrocyte sedimentation rate (ESR) < 30mm/hrS2 -
Moderatemoderate ulcerative colitis: > 4-5 stools daily but with minimal signs of systemic toxicityS3 -
Severesevere ulcerative colitis: ≥ 6 bloody stools daily, pulse > 90 bpm, Temperatures > 37.5, haemoglobin < 105g/L, ESR > 30 mm/hr
Related Pathology
See Also
Viennavienna classification system for inflammatory bowel diseaseParisparis classification for inflammatory bowel disease
-<h4>Introduction</h4><p><strong>Montreal Classification of Inflammatory Bowel disease </strong>is used primarily to classify the severity of <a href="/articles/ulcerative-colitis" title="Ulcerative colitis (UC)">ulcerative colitis </a>and <a href="/articles/crohn-disease-1" title="Crohn's disease">Crohn's disease</a> based on specific categories. This can then be used to guide treatment, discern risk of complications as well as facilitate epidemiological studies <sup>1</sup>. There have been different classifications throughout the years, which have been revised to better capture the dynamic nature of <a href="/articles/inflammatory-bowel-disease" title="Inflammatory bowel disease">inflammatory bowel disease</a>.</p><h4>History and etymology</h4><p>The Rome classification in 1991 proposed by the International Working Party suggested a classification system based on disease extent, anatomical location, behaviour and operative history <sup>2,3</sup>. This was subsequently revised in Vienna at the World Congress of Gastroenterology in 1998, which introduced age of onset as well as including anatomical location and disease behaviour<sup>3</sup>.</p><p>This was further refined in 2005 to be what the Montreal classification is today. The modifications made in the Crohn's disease section included addition of an age group for <16 years, which allows classification for paediatric cases. It also further defines location and behaviour as it was found that upper gastrointestinal cases and perianal disease were not mutually exclusive and could exist in conjunction with other locations and disease behaviours <sup>1,4</sup>. Ulcerative colitis did not have specific sub-classifications listed in the Vienna and Rome classifications, which was introduced with the Montreal classification system. The existing limitation regarding these classifications is that it captures a snap-shot of the disease state as opposed to longitudinally, which is important given the dynamic nature of inflammatory bowel disease <sup>1</sup>.</p><h4>Usage</h4><p>The Montreal classification system's utility in Crohn's disease lies mostly in epidemiological studies to classify the type of Crohn's disease an individual is afflicted with. Clinically, it allows stratification of individuals with regard to their risk of disease progression and complications. Severity for treatment purposes is primarily based on the Crohn's Disease Activity Index - which identifies disease activity based on a point system - as well as biochemical testing <sup>5,6</sup>.</p><p>With regard to ulcerative colitis, its classification can be used to determine severity of disease which can be then used to guide treatment.</p><h4>Classification system</h4><h6>Crohn's disease</h6><ul>- +<h4>Introduction</h4><p><strong>Montreal Classification of inflammatory bowel disease </strong>is used primarily to classify the severity of <a href="/articles/ulcerative-colitis" title="Ulcerative colitis (UC)">ulcerative colitis </a>and <a href="/articles/crohn-disease-1" title="Crohn's disease">Crohn disease</a> based on specific categories. This can then be used to guide treatment, discern risk of complications as well as facilitate epidemiological studies <sup>1</sup>. There have been different classifications throughout the years, which have been revised to better capture the dynamic nature of <a href="/articles/inflammatory-bowel-disease" title="Inflammatory bowel disease">inflammatory bowel disease</a>.</p><h4>History and etymology</h4><p>The Rome classification in 1991 proposed by the International Working Party suggested a classification system based on disease extent, anatomical location, behaviour and operative history <sup>2,3</sup>. This was subsequently revised in Vienna at the World Congress of Gastroenterology in 1998, which introduced age of onset as well as including anatomical location and disease behaviour <sup>3</sup>.</p><p>This was further refined in 2005 to be what the Montreal classification is today. The modifications made in the Crohn disease section included addition of an age group for <16 years, which allows classification for paediatric cases. It also further defines location and behaviour as it was found that upper gastrointestinal cases and perianal disease were not mutually exclusive and could exist in conjunction with other locations and disease behaviours <sup>1,4</sup>. Ulcerative colitis did not have specific sub-classifications listed in the Vienna and Rome classifications, which was introduced with the Montreal classification system. The existing limitation regarding these classifications is that it captures a snap-shot of the disease state as opposed to longitudinally, which is important given the dynamic nature of inflammatory bowel disease <sup>1</sup>.</p><h4>Usage</h4><p>The Montreal classification system's utility in Crohn disease lies mostly in epidemiological studies to classify the type of Crohn disease an individual is afflicted with. Clinically, it allows stratification of individuals with regard to their risk of disease progression and complications. Severity for treatment purposes is primarily based on the Crohn Disease Activity Index - which identifies disease activity based on a point system - as well as biochemical testing <sup>5,6</sup>.</p><p>With regard to ulcerative colitis, its classification can be used to determine severity of disease which can be then used to guide treatment.</p><h4>Classification system</h4><h6>Crohn disease</h6><ul>
-<li><p>L1 - Terminal ileum</p></li>-<li><p>L2 - Colon</p></li>-<li><p>L3 - Ileocolon</p></li>- +<li><p>L1 - terminal ileum</p></li>
- +<li><p>L2 - colon</p></li>
- +<li><p>L3 - ileocolon</p></li>
-<p>L4 - Upper gastrointestinal</p>- +<p>L4 - upper gastrointestinal</p>
-<li><p>B1 - Non-stricturing, non-penetrating</p></li>-<li><p>B2 - Stricturing</p></li>-<li><p>B3 - Penetrating</p></li>- +<li><p>B1 - con-stricturing, non-penetrating</p></li>
- +<li><p>B2 - stricturing</p></li>
- +<li><p>B3 - penetrating</p></li>
-<p>P - Perianal</p>- +<p>P - perianal</p>
-<li><p>E1 - Ulcerative proctitis; involvement limited to rectum (rectosigmoid junction)</p></li>-<li><p>E2 - Left sided ulcerative colitis: involvement limited to portion of colorectum distal to splenic flexure</p></li>-<li><p>E3 - Extensive ulcerative colitis: involvement extends proximal to splenic flexure, 'Pancolitis'</p></li>- +<li><p>E1 - clcerative proctitis; involvement limited to rectum (rectosigmoid junction)</p></li>
- +<li><p>E2 - left sided ulcerative colitis: involvement limited to portion of colorectum distal to splenic flexure</p></li>
- +<li><p>E3 - extensive ulcerative colitis: involvement extends proximal to splenic flexure, 'Pancolitis'</p></li>
-<li><p>S0 - Ulcerative colitis in clinical remission; no symptoms of UC</p></li>-<li><p>S1 - Mild UC ≤ 4 bloody stools daily, lack of fever, pulse <90 bpm, haemoglobin >105g/L, Erythrocyte sedimentation rate (ESR) < 30mm/hr</p></li>-<li><p>S2 - Moderate ulcerative colitis: > 4-5 stools daily but with minimal signs of systemic toxicity</p></li>-<li><p>S3 - Severe ulcerative colitis: ≥ 6 bloody stools daily, pulse > 90 bpm, Temperatures > 37.5, haemoglobin < 105g/L, ESR > 30 mm/hr</p></li>- +<li><p>S0 - ulcerative colitis in clinical remission; no symptoms of UC</p></li>
- +<li><p>S1 - mild UC ≤ 4 bloody stools daily, lack of fever, pulse <90 bpm, haemoglobin >105g/L, Erythrocyte sedimentation rate (ESR) < 30mm/hr</p></li>
- +<li><p>S2 - moderate ulcerative colitis: > 4-5 stools daily but with minimal signs of systemic toxicity</p></li>
- +<li><p>S3 - severe ulcerative colitis: ≥ 6 bloody stools daily, pulse > 90 bpm, Temperatures > 37.5, haemoglobin < 105g/L, ESR > 30 mm/hr</p></li>
-<li><p><a href="/articles/ulcerative-colitis" title="Ulcerative colitis">Ulcerative colitis</a></p></li>-<li><p><a href="/articles/crohn-disease-1" title="Crohn's disease ">Crohn's disease</a></p></li>-<li><p><a href="/articles/inflammatory-bowel-disease-summary" title="Inflammatory bowel disease (summary)">Inflammatory bowel disease</a></p></li>- +<li><p><a href="/articles/ulcerative-colitis" title="Ulcerative colitis">ulcerative colitis</a></p></li>
- +<li><p><a href="/articles/crohn-disease-1" title="Crohn's disease ">crohn disease</a></p></li>
- +<li><p><a href="/articles/inflammatory-bowel-disease-summary" title="Inflammatory bowel disease (summary)">inflammatory bowel disease</a></p></li>
-<li><p>Vienna classification system for inflammatory bowel disease</p></li>-<li><p>Paris classification for inflammatory bowel disease</p></li>- +<li><p>vienna classification system for inflammatory bowel disease</p></li>
- +<li><p>paris classification for inflammatory bowel disease</p></li>