L82 Flashcards
What is Hirschsprung’s disease?
Congenital megacolon
- No ganglia, therefore motility disorder
- Hypertrophic nerves due to compensatory growth
Part behind this area = dilated
Often involves rectum
Presentation of Hirschsprung’s
First few months of life - BABIES
Chronic constipation
Treat Hirschsprung’s
Resection
IBD commonalities on histo
Active inflammation: cryptits, crypt abscesses
Architectural abnormalities: tells you disease is chronic b/c repairs have been happening for a while… the question is which form of IBD
UC histo
IBD histo +
Continuous lesions
Disease in mucosa only
Cryptitis vs crypt abscess
Cryptitis = PMNs in epithelium
Crypt abscess = pus in lumen
Crohn’s histo
IBD histo +
Skip lesions - draw a ling between normal/diseases areas
Granulomas
Transmural inflammation aka deeper than mucosa
Creeping gat = fat bunching up due to scarring of serosal surface
Why are you worried about transmural inflammation of Crohn’s
Scarring/stricture
Perforation
Fistulas
Which form of microscopic colitis has a gender bias?
Collagenous more common in older women
Lymphocytic microscopic colitis histo
Preserved architecture - know its not IBD
More lymphocytes in epithelium than normal (don’t need to be able to dist the difference)
Collagenous microscopic colitis histo
Subepi collagen is thicker than should be
2 classic features of C.diff infection
Pseudomembranes - viable crypts at base means bleeding when you pull one of these
Volcano lesions
What is the difference between acute and chronic ischemic colitis
Acute = necrosis + inflam, ulceration Chronic = fibrosis, scarring of crypts, cellular atypia
What are the 2 neoplastic colon polyps
Adenomatous
Serrated
What mutation gives rise to adenoma polyps
Chromosomal instability pathway mutations
Adenoma polyp histo
Less mucin - cells look darker/more purple
Nuclei are bigger but uniform
What do serrated polyps look like - where in colon found
Might be flat
Often on R side of colon
Serrated polyps histo
Mucin rich
Serrated edges to glands
What mutation leads to FAP
APC = tumor suppressor gene
Example of chromosome instability
Inherit 1 hit, life is gonna give you the 2nd
What mutation leads to HNPCC?
HNPCC = Lynch syndrome
Defected mismatch repair genes
Where in colon is Lynch usually found? What other cancers are you at risk for?
R side - prox colon
Increased risk endometrial and ovarian cancer
What is juvenile polyposis syndrome? Increases risk for what type cancer?
Kids
Inherited - polyps throughout GI
May autoamputate - fall off in poop
Increased risk COLO-RECTAL cancer
What is Peutz Jeghers syndrome? Increased risk of what cancers?
Multiple polyps also associated with intussusception
Increased risk GI + pancreatic cancers
How does an adenoma polyp tun into cancer
Adenoma = by definition low grade dysplasia
High grade
Invasion = see range of atypia, “dirty necrosis”
