012015 diarrhea w infec Flashcards Preview

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Flashcards in 012015 diarrhea w infec Deck (39):
1

clinical course of acute diarrhea

USUALLY SELF LIMITED
usually infectious, but even non-infectious causes will typically resolve

2

etiology of small bowel infectious diarrhea

small bowel inflammed--leading to villous blunting, then malabsoprtion, then gut microbiome utilization of substrate, then abd cramping/bloating/gas/weight loss

cellular or intracellular leaking--mechanism similar to above

3

fever is rare in small bowel infectious diarrhea-true or false

true

4

infectious causes of infectious diarrhea

most gastroenteritis is viral
there's also severe community acquired diarrhea (majority of which is bacterial)

5

can get Salmonella typhi from

poultry, eggs, milk
pet turtles

6

shigella

highly contagious
daycare settings

7

why are antidiarrheal meds not used for infectious diarrhea?

b/c diarrhea is the body's natural way of cleansing out pathogens

8

most common bacterial infectious cause of diarrhea

campylobacter jejuni

9

campylobacter jejuni

influenza like prodrome usually (fever, malaise, myalgias)

10

campylobacter jejuni infectious diarrhea can present also with what other symptoms?

reactive arthritis, erythema nodosum (palpable, painful)
Guillain Barre syndrome

11

like an appendicitis/RLQ pain

Campylobacter jejuni
Yersinia

12

giardia lamblia

acute or chronic diarrhea
upper abdominal bloating
sm bowel disease

13

E coli

colonize healthy GI tract-most are nonpathogenic but a subset cause human disease

14

traveler's diarrhea E coli

enterotoxigenic E coli (ETEC)

15

pathogenesis of ETEC

expresses either heat labile toxin (similar to cholera toxin) or heat stable toxin (which increases cGMP with similar effects)

for heat labile toxin, cAMP causes secretion of Cl through its channel. prevents reabsorption of NaCl at villus tips. so you get net water secretion

16

types of E coli diarrhea

ETEC
EIEC
EAEC
EHEC

17

ATTACHES to enterocytes by adherence fimbriae

EAEC

18

associated with hemolytic uremic syndrome (anemia, thrombocytopenia, uremia)

enterohemorrhagic E coli (EHEC)

19

seafood associated disease (shellfish, plankton)

vibrio cholerae

20

pathogenesis of vibrio cholerae

cholera toxin causes increased cAMP which opens CFTR to release Cl into lumen and draw water out

21

norovirus is common in

adults

22

rotavirus is common in

children

23

which organism can cause pneumonitis?

ascaris lumbricoides (nematode)

24

strongyloides

larvae live in fecally contaminated ground soil-can penetrate unbroken skin such as feet

migrate to lungs from which they are swallowed
mature into adult worms in intestines. eggs can hatch and release larvae that penetrate mucosa--AUTOINFECTION

25

leading cause of iron deficiency anemia in the developing world

necator maericanus and ancylostoma duodenale (hookworms)

they do autoinfection like strongyloides

26

in immunocompromised hosts, what are they likely to get

cryptosporidium parvum
MAC
CMV

27

nosocomial causes of diarrhea

C diff is really important

28

proctitis

suggests rectal cause b/c the rectum is inflammed and in pain with stool there so you want to get it out

29

waking up in the night

rectal cause

30

gas/bloating

small bowel process of C diff

31

hx of fever w diarrhea, think

invasive bacteria
enteric viruses
cytotxic organism (C diff or entamoeba histolytica)
ischemia
IBD

32

why is scoping not helpful really for infectious colitis?

most bacterial infections all induce similar histopathology

33

when should you do stool studies for infectious colitis?

do NOT do for acute and pt who looks good b/c disease is self limited

severely ill
outbreaks
requires hospitalization
immunocompromised pts
pts with comorbdities (IBD)
employees may need the test to return to work

34

ELISAs or DFA microscopy is used more or less commonly than stool test for ova and parasites?

more commonly

35

indications for empiric antibiotics

fever, bloody diarrhea, and presence of occult blood or fecal leukocytes in stool (except for suspected EHEC or C diff)

greater than 8 stools per day, volume depleted, hospitalized, immunocompromised

36

C diff's virulence factors

toxins A, B
etc

37

toxic megacolon

C diff (severe forms)
it's a surgical emergency

38

pseudomembranous colitis

C diff

39

tx for C diff

vancomycin (inpt) and metronidazole (outpt)