Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Microbiology > Enterobacteriaceae Overview > Flashcards

Enterobacteriaceae Overview Flashcards

1
Q

What organism is this?

(Blood Agar)

A

Proteus mirabilis

Swarming on blood agar

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are the general characteristics of Enterobacteriaceae?

A

Gram-negative rod shaped organisms

Ability to reduce nitrates to nitrites (NO3->NO2)

Inability to produce the respiratory enzyme oxidase (oxidase negative)

Facultative anaerobic metabolism (prefers oxygen reduced environment)

Fermentation of glucose (glucose positive)

Growth on MacConkey agar

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What tests are part of IMViC?

What is a positive result?

A

Used to identify an organism in the coliform group (a gram negative aerobic/non-aerobic lactose producing rod)

I: Indole- tests organism for indole production

POSITIVE: a pink/red layering forming on the top of the liquid

M: Methyl Red- detects fermentation of glucose based on acids produced

POSITIVE: red color change

V: VP- tests to see if bacteria can produce acetoin from fermenting glucose

POSITIVE: red color change

C: Citrate: determines if an organism can use citrate for it’s sole carbon source

POSITIVE: blue color change

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Which Enterobacteriaceae are lactose positive?

A
  • Escherichia*
  • Klebciella*
  • Enterobacter*
  • Citrobacter*
  • Serratia marcescens*
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Which Enterobacteriaceae are lactose negative?

A
  • Proteus*
  • Providentia*
  • Salmonella*
  • Shigella*
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the most common clinical isolate?

A

Eschericha coli

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Which Enterobacteriaceae are non-motile?

How would you differentiate these two organisms?

A
  • Klebsiella* (lactose positive)
  • Shigella* (lactose negative)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Which organism is a lactose positive H2S producer?

A

Citrobacter

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Are Pseudomonas and Vibro enterobacteriaceae?

A

NO

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Serratia an Yersinia are _________ (common/rare) clinical isolates.

A

rare

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Which lactose positive organism is indole postitive?

A

E. coli

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Which lactose positive organisms are citrate and VP positive?

How would you differentiate between the two?

A

Klebsiella (non-motile)
Enterobacter (motile)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Describe the Lysine Iron Agar slant test

A

Tests for glucose fermentation, lysine decarboxylation, lysine deamination, and H2S production.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

LIA Slant- interpret slant number 3

A

purple slant/ purple butt

Alkaline slant/ Alkaline butt

K/K

Lysine decarboxylation

No glucose fermentation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

LIA slant- interpret tube #1

A

Purple slant/ yellow butt

Alkaline slant/ Acid butt

K/A

Glucose fermentation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

LIA slant- interpret slant # 2

A

Red slant/ yellow butt

Red slant/ alkaline butt

R/A

Lysine Deamination

Glucose fermentation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

LIA slant- interpret slant #4

A

H2S production

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Describe the Triple Sugar Iron Agar slant

A

Tests and organisms abilty to ferment glucose, lactose, sucrose and tests for gas production and H2S.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

TSI slant- interpret slant number 2

A

Red slant/ Yellow Butt

Alkaline slant/ acid butt

K/A

Glucose positive (glucose only)

20
Q

TSI slant- interpret slant #4

A

Yellow slant/ yellow butt

Acid slant/ Acid butt

A/A

Glucose + Lactose/Sucrose positive

*** this also shows gas production

21
Q

TSI slant- interpret slant #1

A

Red slant/ red butt

alkaline slant/ alkaline butt

K/K

No fermentation

22
Q

TSI slant- interpret slant #3

A

H2S production

23
Q

Describe the urea hydrolysis test (Christiansen’s).

What is a positive result?

A

Tests an organisms ability to produce the enzyme urease.

POS: magenta

NEG: light orange

24
Q

E. coli is normal flora in which part of the body?

A

The gut

25
Q

Most lactose positive gram negative rods will be E. coli if they are also…

A

Indole +

VP -

Citrate -

26
Q

Which are the atigenic determinants of E. coli?

What are they associated with?

A

O antigens- associated with cell wall, heat stable (0157)

K antigens- associated with capsule around cell wall, responsible for inhibition of agglutination by specific antibody

H antigens- associated with flagella (H7)

27
Q

Pathogenic E. coli is most commonly associated with…

A

UTI (uropathogenic E. coli)

Neonatal meningitis

Intestinal disease (gastroenteritis)*** 5 classes (or virotypes) now recognized

Nosocomial Infections

28
Q

E. coli 0157:H7 or EHEC

A

Gastrointestinal E. coli

most life threatening (O and H antigens)

Selective media: MacConkey Sorbitol (SOR -)

Shiga-toxin producer

29
Q

Enterohemorrhagic E. coil (EHEC)

A

Gastrointestinal E. coli

Produces bloody diarrhea often associated with Hemolytic Uremic Syndrom

30
Q

Enteroaggregative E. coli (EAEC)

A

Gastrointestinal E. coli

Recovered from children with chronic diarrhea

31
Q

Enterotoxigenis E. coli (ETEC)

A

Gastrointestinal E. coli

Produces heat stable (ST) and heat labile (LT) toxins

Traveler’s diarrhea

32
Q

Enteroinvasive E. coli (EIEC)

A

Gastrointestinal E. coli

Produces a dysentery-like disease in poor nations

33
Q

Enteropathogenic E. coli (EPEC)

A

Gastrointestinal E. coli

Produces a profound diarrhea in infants in poor nations

34
Q

Klebsiella pneumoniae has ____ and ____ antigens which may be typed.

A

O and K antigens

35
Q

Klebsiella pneumonia specimens of choice

A

urine (UTI)

deep cough (pneumonia)

36
Q

Citrobacter freundii is normal flora in…….

It causes infrequent cases of…….

A

human gastrointestinal tract

UTI and RTI

37
Q

Proteus mirabilis is found in…

A

manure

sewage

soil

38
Q

Proteus mirabilis is responsible for…

A

Antibiotic diarrhea (multiple drug resistance)

UTI

Promotes kidney stones

Abscesses, pyelonphritis, cystis, infant diarrhea

39
Q

What are the 3 categories of Salmonella?

A

Gastroenteritis and diarrhea

Bacteremia/ extraintestinal infection

Enteric Fever (typhoid fever)

40
Q

How does the Kauffman-White scheme of serotyping identify diffrent groups of Salmonell?

A

heat stable O antigen

heat-liable H antigen

heat-liable Vi antigen

41
Q

Where is Salmonella commonly found?

What dieseses are associated with it?

A

Animals- reptiles, pet turtles, fowls

Food- eggs, meat, mayo

Food poisoning

Paratyphoid fever

Bacteremia

Salmonellosis

* Mistaken as Fever of Unknown Origin (FUO)

42
Q

How long does it take for symptoms to present with Salmonella food poisoning?

Staphylococcal food poisoning?

A

Salmonella: 10-28 hours

Staphylococcus: 2-6 hours

43
Q

Shigella are identified ________ with _____antigens.

A

serologically, O

44
Q

Shigella sonnei

Host?

Infections?

A

Humans

Watery diarrhea (crowding and unsanitary conditions)

Shigellosis (from fecally contaminated water or food)

** Produce potent toxins, no bacteremias

45
Q

Yersinia enterocolitica

Reservoir?

Infections?

A

Dogs, cats, rodents, pigs, cattle

Food/Drink vehicle

Infection mimics appendicitis

46
Q

Agar?

Organism?

Colony Appearance?

A

CIN

Yersinia

Dark-red bullseye colonies

Microbiology (11 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions