GI

Question 1

lab results of Salmonella enteritidis

Answer 1

macconkey lacotse plates - white/uncolored colonies
heketoen plates - produce H2S gas, forms dark centers
oxidase negative
API Strips

Question 2

C. jejuni enterocolitis lab results?

Answer 2

gram negative
helically curved rods in pairs
"gull wings"
single flagellum
microaerophilic
CampyBAP medium
oxidase positive

Question 3

why is antibiotic therapy not recommended for Enterohemorrhagic E. coli?

Answer 3

because it up regulates the production of shiga toxins which would garuntee paralysis or death before the antibiotic kills the bacteria

Question 4

shigellae lab results?

Answer 4

most are Lac -
Macconkey lactose plates - white/uncolored colonies
Hektoen plate - green colonies
Do NOT produce H2S gas - colonies do not have dark centers
oxidase negative

Question 5

E. coli lab results?

Answer 5

Macconkey agar - Lactose +
oxidase negative
serology - O and H antigens
API strips

Question 6

Vibrio cholerae lab results?

Answer 6

gram negative
curved rods
thiocitrate bile salts sucrose (TCBS) medium
oxidase +
serological tests- O and Ag
PCR

Question 7

Enteric bacteria lab results?

Answer 7

all gram negative
carbohydrate fermentation tests
grows in low O2 
Serology - O, K, H antigens; agglutination of oantigens in stool
presence or absence of specific enzymes
pcr

Question 8

list family members of enterobacteriaceae

Answer 8

E.coli,
Salmonella enterididtis
Shigella
Salmonella typhi

Question 9

list family members of vibrionaceae

Answer 9

V. cholerae
campylobacter jejuni
helicobacter pylori

Question 10

agents of watery diarhea?

Answer 10

EPEC
EAEC
DAEC
all of these are diff types of E.coli

Question 11

virulence factors of watery diarhea?

Answer 11

pili

cholera toxins to decrease Na+ absorption and increase Cl- secretion

Question 12

diarrhea features

Answer 12

non inflammatory
small intestine
flu8id and electolyte loss
host forcibly expells the pathogen

Question 13

dysentery

Answer 13

inflammatory disorder
large intestine
invasion of colonic wall
blood and pus in feces
enterotoxin commonly
pain fever cramps

Question 14

enterobacteriaceae vs vibrionacaeia

Answer 14

enterobacteriaceae:
gram negative
capsule/slime layer
can be motile or non motile
pili
speciation by fermentation of carbohydrates, O and H Ags
vibrionaceae:
gram negative
no capsules
highly motile
curved rods
pili
Speciation by serology - O and Ag

Question 15

ETEC (travelors diarhea) toxin

Answer 15

Heat liable

heat stable

Question 16

what are the types of GI Diseases?

Answer 16

watery diarrhea
dysentery (bloody diarrhea)
peptic ulcers

Question 17

colonization and growth vs intoxication

Answer 17

colonization and growth requires presence of living bacteria
Examples: salmonella gastroenteritis, bacillary dysentery, cholera
Intoxication does not require presence of living bacteria
examples: staphyloccocal and clostidial botulism food poisonings

Question 18

dysentry vs bloody diarrhea

Answer 18

Dysentry - frequent passage of low volume stools with blood, MUCUS, and pus
bloody diarrhea - lots of liquid, bloody, pus, stools

Question 19

hemorrhagic colitis

Answer 19

lots of liquid blood stools with NO LEUKOCYTES

Question 20

bacillary dysentery

Answer 20

transmission is the 4 f's
fingers, flies, food, feces
affects colon; GI tract
common in day care and institutions
symptoms: fever, damage to colonic cells, bloody and mucus stool (dysentery)
Treatment is rehydration and antibiotics
prevention is handwashing

Question 21

why is shigellae non motile

Answer 21

because it only has O antigen and not H antigen

Question 22

what is the shigellae toxin?

Answer 22

shiga toxin is enterotoxin which inactivates rRNA and causes no protein synthesis and cell death

Question 23

E.coli

Answer 23

"hamburger syndrome"
EHEC h for hamburger
produces shiga like toxins which kills glomerular cells of kidney and CNS endothelial cells which cause paralysis
hemolytic uremic syndrome 
serotype O157:H7

Question 24

enterohemorrhagic e. coli (EHEC) lab results

Answer 24

Sorbitol macconkey plates - EHEC is sorbital neg. (white)
serology for O157
shiga toxin in stool
antibiotic therapy not recommended b/c it will speed production of shiga toxins before antibiotic kills bacteria which garuntees paralysis or death

Question 25

what systemic diseases can salmonella enterica cuase?

Answer 25

gastroenteritis
typhoid fever
septicemia

Question 26

salmonella gastroenteritis

Answer 26

from chickens and eggs
coloniztion
diarrhea, nausea, vomiting, fever, abdominal pain
no treatment

Question 27

Salmonella. enteritidis

Answer 27

pili and long flagella
macconkey lactose plates : white colonies
hektoen plates: make H2S gas, colonies with dark center
oxidase negative

Question 28

typhoid fever

Answer 28

slow onset
caused by salmonella enterica typhi
starts with organism penetrating intestinal wall
then organism invades bloodstream and biliary tree
diarrhea, fever
exhaustion

Question 29

typhoid fever diagnosis and treatment

Answer 29

serology: IgM Abs
IgG Abs
Vi antigen
Treatment - antibiotics

Question 30

viruelnce and prevention of typhoid

Answer 30

virulence;
capsule
flagella (H antigen)
LPS endotoxin
cell invasion machinery
survive and multiplies in macrophages
Prevention:
Vaccines

Question 31

example of enterobacteriacae?

examples of vibrionaceae

Answer 31

enterobacteriaceae:
escherichia coli (diarrhea, hemorrhagic colitis, dysentery)
shigella dysenteriae (dysentery)
salmonella typhi (typhoid fever)
vibrionaceae :
vibrio cholerae (cholera)
helicobacter pylori (peptic ulcer)
gastroenteritis (Vibrio parahemolyticus)
campylobacter jejuni (diarrhea)