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Flashcards in GI 6 Deck (52):
1

similar to shigellosis but less severe ..and what does shigellosis have that this condition does not

enteroinvasive e. coli (EIEC)

does not have a shiga toxin

2

pathogenesis of enteroinvasive e. coli (EIEC)

invades the enterocytes of LI (like shigellosis)

3

what are the different types of salmonella genus based on

Vi antigens (capsular)

4

3 clinical manifestations of salmonella

gastroenteritis, septicemia/bacterial, enteric (typhoid) fever

5

bacteria associated enteric typhoid fever

Salmonella Typhi

6

tests that you order for the different symptoms of salmonella

-enterocolitis: positive in stool culture soon after test but not seen in blood
-septicemia/bacteremia: pos in blood culture during high fever and sometimes seen in stool
-enteric typhoid fever: pos in blood culture for 1st and 2nd week then pos from 2nd week and on in stool

7

pathogenesis of salmonella

they all will invade SI and sometimes LI but only septicemia/bacteremia will go the lymphatics then enter the blood and become systemic

8

what harbors salmonella that leads to enterocolitis/gastroenteritis

it is food borne infection and seen mainly in dairy/poultry products

9

who is mainly infected with reptile associated salmonella

infants and children through direct or indirect contact

10

who in the US is infected with enteric typhoid fever

those that have travelled to Asia, Mexico, and India

11

what occurs if enteric typhoid fever goes systemic

it can enter the liver/gall bladder and replicate in the bile and then bile enter the SI and reinfects leading to inflammation and ulceration

of course if it gets to SI --> seen in feces

12

types of people who are important/dangerous in the transmission of typhoid fever

carriers because they have no symptoms but yet shed and infect others

13

how can you prevent transmission of typhoid fever

take out the gall bladder so there will be no site for microbe to multiply and shed in feces

14

how do you isolate and detect salmonella

use McConkey's agar or S-S agar (salmonella -shigella agar)

15

what do you see on S-S agar for salmonella

colorless/pale because salmonella does not do lactose fermentation

16

how do you differentiate salmonella from shigella

salmonella is motile while shigella is not
salmonella uses gas from glucose
salmonella does H2S production and shigella does not (with the exception of s. flexnieri)

17

diagnostic feature of s. typhi

-S-S agar
-history of travel to endemic areas like Asia, Mexico, and India
-Positive widal reaction
-gram neg, motile bacteria

18

morphological feature of campylobacter

gram neg, motile, microaerophilic, does not ferment CH2O, and catalase positive

19

carrier of campylobacter coli

pigs

20

in general, how does one get infected with campylobacter

fecal contaminated water
unpasteurized milk
raw/partially cooked poultry

21

toxins of campylobacter

-endotoxin
-enterotoxin --> watery diarrhea
-cytotoxin: verotoxin (similar to shiga toxin) --> bloody diarrhea

22

clinical symptoms of campylobacter

symptoms begin 3-5 days after ingestion
-pyrexia (raised temp - fever)
-prostration
-abdominal pain
-diarrhea

23

complications of campylobacter

-reactive arthritis
-guillian barre (aka acute motor axonal neuropathy) which is a symmetric ascending paralysis

24

detection of c. jejuni

fecal specimen culture --> gram neg, motile, catalase pos, microaerophilic, needs 10% CO2

25

Yersinia enterolytica is common in what age group

children under the age of 7

26

what other condition rivals yersinia enterolytica

salmonella acute gastroenteritis because of commonality in cooler climates

yersinia is a pyschrotroph - facultative psyhcrophile

27

pathogenesis of yersinia enterolytica

releases a ST enterotoxin that increases cGMP --> watery diarrhea

induces invasive inflammation in the distal ileum and adjacent tissues and mesenteric lymph node hence mimicking appendicitis

28

treatment of yersinia enterolytica

doxycycline and oxytetracycline

29

complication of yersinia enterolytica

post-infective reactive arthritis (autoimmunity arthritis)

30

what are the non cholera vibrios

v. parahemolyticus
v. alginolyticus
v. vulnificus
v. cholerae (non toxigenic v. cholerae)

31

features of non cholerae vibrios

not agglutinated by anti 01 sera
halophilic organisms (common coastal waters)

32

how does one get vibrio parahemolyticus and in what area of the world is it common

from eating raw or undercooked seafood
common in Japan - they eat raw fish (sushi)

33

how does one get infected with vibrio vulnificus

eating raw oysters

34

clinical features of vibrio vulnificus

it is a virulent strain
get intense skin lesions --> gastroenteritis and severe bacteremia

35

how do you diagnose vibrio

screening stool for oxidase activity
TCBS agar - thiosulfate citrate bile salt sucrose agar --> sucrose negative will be vibrio parahemolyticus and vibrio vulnificus

36

what does enteroaggregative possess

AAF - aggregative adherence factor

37

another name for STEC - shiga toxin producing e. coli

VTEC - verotoxin producing e. coli

38

what can STEC/VTEC cause

hemorrhagic colitis
hemolytic uremic syndrome
thrombotic thrombocytopenia purpura

39

which one of the STEC/VTEC affect adults and which children and which elderly

hemorrhagic colitis - adults
hemolytic uremic syndrome - children
thrombotic thrombocytopenia purpura - elderly

40

toxin released by VTEC/STEC

verotoxin released and it causes inhibition of protein synthesis (which is why it is called shiga like toxin e coli)

41

worst thing you can do in patients with VTEC/STEC and why

treat them with antibiotics because the killed organism will release more toxin causing even more damage

42

what is screened for in routine stool culture? what if it is bloody?

routine - campylobacter, shigella, salmonella
if bloody - STEC/VTEC

43

complication of a pseudopod forming protozoa

entamoeba histolytica
toxic megacolon

44

how does one get infected with balantidum coli

contaminated water or food by pig feces

45

pathogenesis of balantidum coli

you ingest cyst --> becomes trophozoite which invades the SI --> into LI to invade colon --> shed cyst and trophozoite in the feces

46

diagnosis of balantidum coli

ciliated trophozoite in the feces because cysts are not frequent

47

manifestations of ascaris lumbricoides and treatment

asymptomatic --> but could be pulmonary symptoms
treat with albendazole

48

how would you describe the ascaris lumbricoides worm

large white/pink adult worm that is 15-25 cm long

49

clinical manifestation of trichuris trichuria especially in children

asymptomatic with peripheral blood eosinophilia
in children - iron deficiency and growth retardation

50

treatment of trichuris trichura

albendazole just like ascaris (both are worms that gives you eosinophilia)

51

manifestation of anyclostoma duodenale nectar americanus

iron deficiency and protein energy malnutrition especially in children and women of child bearing age

52

treatment of ancylostoma duodenale nectar americanus

albendazole and iron replacement