Flashcards in 135b Colonic disorder histo Deck (31):
large intestine histo
perpendicular tubules extending to muscularis mucosae with a lot of goblet cells (fewer absorption cells than small intestine)
some lymhoid nodules
colon main fxn
absorption of water
transport of fecal mater
Pseudomembraneous colitis (PMC) - what is it? what causes it?
necrotic epi cells with acute inflammatory (PMNs) cells and fibrinous material
caused - antibiotic --> C. Diff + any other colitis
color of PMC
creamy yellow plaque - may be diffuse or patchy
C. Diff appearance? what histo appearance can it cause in the colon? how?
gram + rod
pseudomembranes via toxins --> damage epi/endo cells --> inflammation
ulcerative colitis - where does it start?
rectum (crohn's usually doesn't affect rectum)
can progress to the entire colon in a continuous fashion
idiopathic inflamm bowel disease - types (2)?
what increases risk for both?
family hx (genetic factor) + environmental action
ulcerative coloitis - what does it affect?
mucus membrane inflammation only (crohn's is transmural)
UC presenting age
smoking risk for UC and Crohn's
increases Crohn's risk
decreases UC risk
UC vs Crohn's - which one is continuous?
Crohn's is discontinuous (skip, cobblestones)
UC vs Crohn's - which involves rectum always?
UC vs Crohn's - which never involves terminal ileum?
Crohn's 60% + anal lesions
UC vs Crohn's - which is transmural inflammation?
crohn's - linear/knife like
UC - mucous inflammation
UC vs Crohn's - which involves strictures and fistulas?
UC vs Crohn's- which never has granulomas?
Crohn's present 50%
UC vs Crohn's - which has crypt abscess and pseudopolyps?
complications of UC?
neoplastic colon polyps - types and location? what is the most important factor for risk of cancer progession?
tubular adenoma - descending colon
villous adenoma - rectum
size is most important factor (>1 cm = bad)
cancer/dysplasia - high risk for UC patients?
onset in childhood
duration of disease > 10 years
what is the colitis cancer?
mucinous/signet cell carcinoma?
familial polyposis (FAP) - cause
germ line mutation of APC (Gatekeeper)
Adenocarcinoma of colon and rectum - risk factors?
familial polyposis (FAP) - appearance
> 100 polyps/adenomas in colon and rectum
familial polyposis (FAP) - when do polyps appear? symtoms? cancer?
Adenocarcinoma of colon and rectum - diet risk? genetics?
high fat diet + genetics
what inhibits aging, decreases cancer?
25% reduction in caloric intake
cancer - genetics?
lynch syndrome - hereditary nonpolyposis colorectal cancer -- genetics?
AD - mutation in BRAF (mutation repair) --> microsatellite instability ?
where do most colon carcinomas present?
75% in sigmoid and distal
almost all adenocarcinomas