Another favorite boards topic – diarrhea. Diarrhea can of course be divided multiple
ways – acute vs. chronic, secretory vs. osmotic vs. inflammatory, small-bowel vs. large-
bowel. Be able to easily distinguish the two main types of inflammatory diarrhea,
Ulcerative colitis vs. Crohn’s. Since this was already discussed in the last GI blog, I’ll
just address some key words for each.
Remember:
Ulcerative colitis – Crampy pain. Mucosa and submucosa. Pseudopolyps.
HLA-B27. Ankylosing spondylitis. Pyoderma gangrenosum. Primary
sclerosing cholangitis. Toxic megacolon. Adenocarcinoma.
Crohn’s disease – Colicky pain. Transmural. Lymphocytes. Granulomas.
Rectal sparing. Skip lesions. Fistulas. Strictures. B12 deficiency.
Both conditions usually present with diarrhea on the boards, so be able to quickly
recognize these key words for some easy points. Don’t forget, both of these conditions
have an increased risk of colon cancer estimated to be 1-2% per year after 8 years of
disease. Thus surveillance colonoscopy should be started in patients with IBD for 8
years or longer.