Phenotypic evolution of Crohn's disease occurs in whites but has never been described in other populations.
The Montreal classification may describe phenotypes more precisely.
Dr Dorothy Chow and colleagues from Hong Kong validated the Montreal classification through a longitudinal sensitivity analysis in detecting phenotypic variation compared to the Vienna classification.
|31% of patients underwent major surgery|
|Inflammatory Bowel Diseases|
The research team conducted a retrospective longitudinal study of consecutive Chinese Crohn's disease patients.
All cases were classified by the Montreal classification and the Vienna classification for behavior and location.
The evolution of these characteristics and the need for surgery were evaluated.
The researchers recruited a total of 109 patients, with a median follow-up 4 years.
Crohn's disease behavior changed 3 years after diagnosis, with an increase in stricturing and penetrating phenotypes, as determined by the Montreal classification.
However, this was only detected by the Vienna classification after 5 years.
Disease location remained stable on follow-up in both classifications.
The research team found that 31% of patients underwent major surgery during the follow-up period with the stricturing, and penetrating phenotypes.
In contrast, colonic disease was protective against a major operation.
Dr Chow's team concluded, "This is the first study demonstrating phenotypic evolution of Crohn's disease in a nonwhite population."
"The Montreal classification is more sensitive to behavior phenotypic changes than is the Vienna classification after excluding perianal disease from the penetrating disease category, and was useful in predicting course and the need for surgery."