American Board of Internal Medicine (ABIM) Certification Practice Exam

Which drug can be used to treat severe cases of microscopic colitis?

1. Corticosteroids

2. Budesonide

3. Infliximab

4. Mesalamine

The correct answer is: Budesonide

In cases of severe microscopic colitis, budesonide is often the drug of choice due to its favorable profile in terms of efficacy and side effects. Budesonide is a corticosteroid that is formulated to have a high local effect in the gastrointestinal tract while minimizing systemic absorption. This makes it particularly useful for treating inflammatory conditions like microscopic colitis without the significant systemic side effects associated with traditional corticosteroids. Specifically, budesonide targets the underlying inflammation of the bowel mucosa, helping to reduce symptoms such as diarrhea and abdominal pain, which are characteristic of microscopic colitis. The other options, while they may have roles in managing gastrointestinal conditions, are not as well established or effective for this particular diagnosis. For instance, while corticosteroids can be broadly effective, they are less targeted than budesonide and can have more pronounced systemic effects. Infliximab, a biologic agent, is typically used for more severe inflammatory bowel diseases like Crohn's disease and ulcerative colitis, rather than microscopic colitis. Mesalamine is generally used for inflammatory bowel diseases as well, but it is not as effective in managing the specific inflammation associated with microscopic colitis as budesonide is. Thus, budesonide’s targeted action specifically within