Since Crohn's is determined by in part by genetics, my view is that one is predisposed to a certain level of disease. How sick you actually become is dictated by environmental triggers, medication you take, and age--probably it can change over your lifetime. That's just my opinion--I'm no expert.
Based on that logic, a person "has" aggressive Crohn's no matter what medication they are currently on; it's always there in the background, and could become very severe illness if given the opportunity. But with adequate control, symptoms could be much milder. I thought the mild/moderate/severe designations had more to do with your current symptoms than the overall pattern of disease behavior.
To give a brief summary of info you can find in a journal article (ref below):
Doctors classify Crohn's based on age of onset, location, and behavior. The three patterns of behavior are perforating (fistula/abcess/perforation type), stricturing (fibrostenotic stricture/obstruction type), and nonperforating/nonpenetrating (inflammatory type). Based on your daughter's fistula she falls into the first type, which is unfortunately probably the most complex and aggressive form, and often requires a combination of medical therapy and surgery. Fistulas can be quite difficult to treat once they occur, so that is probably a strong incentive for her to stay on medication, with close monitoring by her GI.
Are there different types of Crohn's disease? David B. Sachar, MD
Inflammatory Bowel Disease Volume 14, Issue S2, Pages S75-S76
July 2007 Drug-Induced Liver Injury
January 2008 Crohn's IleitisCurrently trying...
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