2 Disease of lower GI: path - [3] deveraj Flashcards Preview

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Flashcards in 2 Disease of lower GI: path - [3] deveraj Deck (20):
1

pathogenesis of Celiac disease (gluten sensitive enteropathy)

Gluten digested by luminel + brush border enzymes →
exposure to α-gliadin peptide results in autoAb formation →
inflammation (↑ T lymph) →
villous atrophy →
tissue damage →
loss of mucosal and brush border surface area →
malabsorption, diarrhea

2

classical presentation of celiacs

bulky fatty diarrhea
flatulence
weight loss
anemia
nutritional deficiencies
growth failure in children

3

3 characteristic findings in tissue biopsy for Celiacs

Endoscopy findings?

1. villous blunting
2. increased intraepithelial lymphocytes
3. lymphoplasmacytosis of the lamina propria

scalloped appearance
(*note: IgA ab to TTG and anti-endomysial ab)

4

celiacs disease is associated with the blistering skin disease _____

dermatitis herpetiformis

5

Pathogenesis of Whipple disease

caused by gram (+) bacilli Tropheryma whippelii
- bacilli absorbed by lamina propria macrophages →
organism-laden mac. accumulate in sm Int lamina propria + mesenteric lymph nodes → lymphatic obstruction →
malabsorptive diarrhea

"foamy macrophages"

6

clinical features of whipple disease

triad of:
diarrhea, weight loss, malabsorption

typically in middle ages or elderly white males

7

Giardia lamblia
- what
- dx
-sx
-tx

protozoan parasite
waterborne + Cl resistant

dx: trophozites or cysts (cute purple smiley guy)
sx: bloating, flatulence, foul smelling fatty diarrhea
tx: metronidazole

8

Infectious enterocolITIS
- bacterial infections

typically create an acute self-limited colitis

pts usually present several weeks after onset of sx, so tisue biopsy rarely shows classic acute infectious findings

- campylobacter
- shigellosis
- salmonellosis
- E. coli

9

Campylobacter spp
- Gram ___
- usually found ____
- Presentation

gram NEGATIVE major cause of diarrhea worldwide
a leading cause of bacterial foodborne illness in US
- found in contaminated meat (poultry), water, and unpasteurized dairy
Prod. WATERY diarrhea +/- blood

Infectious enterocolITIS

10

Salmonella
- Gram ___
- usually found ____
- Presentation
- Characteristic pathology most commonly seen in:

gram NEGATIVE
food and water
- food poisoning + travelers diarrhea
- typhoid mary
Prod diarrhea @ 2nd week of infxn initially watery then bloody
ileum, colon, appendix, Peyer's patches

Infectious enterocolITIS

11

Enterohemorrhagic E. Coli
pathology
sx
endoscopy
area of colon affected

[O157:H7] "jack in the box"
non invasive, toxin producing, contaminated hamburgers
bloody diarrhea, severe cramps, mild or no fever, renal failure maybe

12

Pseudomembranous colitis
- commonly caused by
- susceptibility factor?
- sx?
- type of diarrhea?

C. diff
colitis often occurs after course of antibiotic therapy
"antibiotic associated colitis"
- 3rd gen cephalosporins
common in hospitalized pts

sx: fever, leukocytosis, abdominal pain, cramps, watery diarrhea

13

which virus is the most common cause of severe childhood diarrhea and diarrheal mortality worldwide?
- path?

rotavirus
- children 6-24 mo vulnerable

infects and destroys mature enterocytes →
villus surface repopulated by immature secretory cells →
loss of absorptive fxn →
net secretion of water and electrolytes →
osmotic diarrhea →
DEHYDRATION

2 vaccines now available

14

Indiv at risk for ischemic colitis

older indiv w/ co-existing cardiac or vascular disease
young pts: long distance runners, women on oral con.
mech. obstruction: hernias, volvulus

- splenic flexure + rectosigmoid area at risk (watershed)

15

presentation of ischemic colitis

acute transmural infarction → severe abdominal pain
tenderness
n/v
bloody diarrhea
PERISTALSIS SOUNDS DISAPPEAR
rigid abdomen
shock/sepsis

16

what makes up the pseudomembrane in PC?

adherent layer of inflammatory cells and mucinous debris at sites of colonic mucosal injury

surface epithelium denuded, mucopurulent exudates

17

Two histological patterns associated with microscopic colitis

1. collagenous colitis
- thickened subepithelial collagen layer
- too many lymphocytes in LP

2. lymphocytic colitis
- increased intraepithelial lymphocyte
- too many lymphocytes in LP

18

Does crohns or UC present worse distally by rectum and present with pseudopolyps and has thinner walls

UC

19

Primary sclerosing cholangitis (PSC) is heavily associated with ____

UC

20

fecalith pathopneumonic for ______

appendicitis
- inflammatory response