Diarrhea Acute

Question 1

duration

Etiology

Noninfect causes

Answer 1

less than 2 wks

usually infectous

drugs/GI dz/systemic states

Question 2

Infections are typically

presentation

transmission

Answer 2

viral- norovirus/rota/adeno

self limited diarrhea/ab cramping

foodborne

Question 3

Bacterial transmission

coastal areas w ingested shellfish bacteria

Campylobacter

Salmonella

Shigella

E coli (enterotoxigenic)

Yersinia

Sources

Answer 3

foodborne

Vibrio parahemolytica

poultry, unpast mild

poultry, eggs, dairy, pets

poultry, mayo salads, fecal oral

uncooked meat

pork

Question 4

travelers diarrhea

Vibrio cholera geo

transmission

Answer 4

E coli

Africa, SE/E Asia, americas

contam water/food

Question 5

common us parasites

Crypto trans

Unusual

Giardia trasmission

Answer 5

crypto, giardia

contam food/water or person to person

Chlorine does not kill crypto

contam water/kids @ daycare

Question 6

Entamoeba histolytica geo

CM

complication

Answer 6

resource poor

asx

ameba ascend portal vein system, leading to liver abscess

Question 7

Nematode infections

hookworms cm

Trichuris trichuria geo

Answer 7

unlikely for diarrhea

epigastric pain, nausea, d

tropical countries

Question 8

Organism, presentation, transmission, dx

Enterobius (pinworm)

Trichuris (whipworm)

Necator americanus/Ancyclostoma (hookworm)

Ascaris lumbricoides (roundworm)

Strongyloides (threadworm)

Answer 8

Perianal pruritis, vulvovaginits- ingest eggs, PtP- perianal eggs

loose stool, mucus/blood- ingest eggs/soil-eggs in stool

Pruritic rash, ab pain, Fe def anemia- skin penetration (Asia/Africa/SA/SEUS)- eggs in stool/eosinopilia

Cough/SOB/IO- ingest eggs from food/water (same areas)-same

Duodenitis/Cough/SOB/hemoptysis- skin penetration and soil (SE Asia/US)- larva in stool/eos

Question 9

Typical parasite diarrhea mechanism

Viral orgs result in

Rotavirus

Vibria cholera

eventually leads to

Answer 9

secretory etiology

direct damage to intes epithelium, leading to mucosal loss of fluid

enterotoxin (NSP4)- inc IC Ca, efflux Cl into lumen

secretory diarrhea- binds GP, activates AC, cAMP- CFTR chloride channel

efflux of Cl/water/Na/K/bicarb

Question 10

ETEC

shigella

Answer 10

same as cholera

multiple enterotoxins- secretory diarrhea

Question 11

Lost microvilli/diminished BB enzymes problem

Noravirus

Rotavirus

difference

Answer 11

inc carbs/proteins in gut- osmotic diarrhea (inc lumen)

blunts MV, malabsorbs fat/carbs

destroys villous epithelial cells/ blunts intestinal villi- decreased SA

N- self limited
R- much longer

Question 12

Inflammation releases

results in

Shigella process

EHEC and Shigella shiga toxin

once systemic

Answer 12

cytokines- stimulate sec/motility

fat malabsroption/lost BA

invades mucosal cells, induce inflamm rxn- shallow ulcers form

bind epi surface proteins/endocytosis and stop protein synthesis (cell death)

targets endo cells, vasc damage and prothrombotic (Hemo/uremic)

Question 13

AB associated diarrhea

inc carb solutes in intestinal lumen

deconjugated bile salts

erythromycin

clavulanate

if dec flora sign, can lead to

Answer 13

dec colonic flora, problems w carb/BA metabolism

osmotic diarrhea

secretory

binds motilin receptors, inc gastric emptying

intestinal motility

c diff

Question 14

Osmotic diarrhea

Secretory diarrhea

Maldigestion

Altered motility diarrhea

Non antibiotic diarrhea mchs

Answer 14

nonabsorb carbs (PEG, sorb, man, lactulose, Mg)

activate AC, cAMP, inhibit Na/K atpase

lipase inhibitors

inc motility shortens transit

Question 15

Watery diarrhea due to

MC

Bacteria include

Noravirus month/place

cm

most likely to cause

resolves in

Answer 15

usually infection

viruses

Camp, c diff, ETEC, salm, shigella, V parah, Yersinia

cold/cruise ships

NV/diarrhea/cramp

vomiting

48-72 hrs

Question 16

Rotavirus is more

children

Answer 16

prolonged

worse course

Question 17

Small volume stools w blood/mcus suggests

bloody diarrhea suggest

potential cause in IC patient

EHEC course

hemolytic/uremia

triad

Answer 17

colitis w severe pain/tenesmus

bacteria- EHEC, shigella, camp, Salm, Yers

CMV

3-4 days after ingestion- bloody diarrhea No FEVER

big concern, kids esp

AKI, micro hemolytic anemia, thrombo 5-10 days later

Question 18

Salmonella transmission

CM

Sigella trsn

Answer 18

food/reptiles

watery diarrhea/bloody/high fever

food- same presentation, NV, freq stools, fluid loss is LARGE

Question 19

Camylobacter trsn

adults

presntation

PE

late complication

Answer 19

contam food- same presn

pan/fever less common, mimics appendicitis

iliocecal area inflamed/enlarged LAD

RLG pain, RT

Guillan Barre- ab to epitopes cross react w GM1 ganglioside in PN myelin

Question 20

Yersinia trsn

CM

also mimics

Answer 20

food products

fever, bloody/mucus d/ v

appendicitis

Question 21

Need for further eval w sx such as

Workup

Answer 21

High F, severe diarrhe/fluid loss
Bloody stools, IC, +7 days

Fecal lactoferrin (+ suggests inflam)
Bacterial stool culture/PCR
C diff toxin/PCR
Ova/parasite test w travel

Question 22

Mx of watery diarrhea

if severe dehydration/cant tolerate oral

Children w persisten vomiting/diarrhea to reduce need for rehydraion/hosp

Answer 22

supportive-oral balanced salts to replace lost water/Na/K/bicarb

IV

odansetron

Question 23

Adults w watery diarrhea

avoid if

other agents to use

Answer 23

antimotilty to stop secretion (if healthy/no RF)

severe inf, C diff

loperamide/bismuth

Question 24

Watery diarrhea and AB

exception

Bloody diarrhea- avoid

AB may ____ in E coli and shigella

Only use AB to treat

Answer 24

no effect

ETEC- use cipro
C diff

AB

inc expression/release of toxin

Camp, salmon, yersinia, shigella (no toxin)