Brainscape's Knowledge GenomeTM

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


See full index

Bacteriology > Enterobacteriaceae- E coli > Flashcards

Enterobacteriaceae- E coli Flashcards

1
Q

Enterobacteriaceae overview

A 
Reside in the GI tract of humans and animals 
Benefits: microbian antagonism
-breakdown and absorption of the food
-Waste processing
-Vitamin K production
40 genera, 180 spp
Gram -
facultative anaerobic
Rods or coccobacilli
Oxidase negative
Present in water, soil environment and GI tract of humans and animals- not environmental really
Coliform bacteria
Lactose += ecoli,
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Genus Escherichia

A

E. coli- only clinically relevant one
Major pathogen in several animal species
Gram-negative coccobacilli
Lactose positive, oxidase negative, motile rods

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

E. Coli

A

Serotype: complete antigenic formula of an E coli
ex. O:26, K:60, F:41, H:11
O- O antigen (surface antigen- part of LPS)
H-Flagella
F-Fimbriae
K-Capsule
V diverse

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

E. Coli: pathogenicity

A

Strain dependent
Facultative pathogenic (eg. APEC)
Obligate pathogenic but then age dependent (few)
Differentiation between pathogenic and non-pathogenic strains not always evident but associated with:
-Certain serotypes (serotyping)
-Virulence genes (pathotyping-virotyping)
-Combinations of virulence genes
-Biotype (for RPEC only)

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

E. Coli: infections

A 
Intestinal pathogenic strains
Extra-intestinal pathogenic strains (ExPEC)
-Respiratory
-Septicemia
-UTI
-Pyometra
-Mastitis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

E. Coli: virulence factors

A 
Depend on the pathotype
Cell associated:
-Endotoxin
-Capsule
-Fimbrial adhesions
-Non-fimbrial adhesions

Extracellular

  • Enterotoxins (work on intestine)
  • Cytotoxins (toxicity for other cell types)
  • Siderophores (septicemia)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

E. Coli: Enteric Pathotypes

A 
ETEC (enterotoxigenic)
EHEC (Enterohemorrhagic)
VTEC/STEC (Verotoxigenic/Shiga-like toxic)
EPEC (Enteropathogenic)
RPEC (Rabbit pathogenic)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

E. Coli: Extra-intestinal pathotypes

A 
APEC (Avian pathogenic)
Necrotoxigenic (NTEC)- cattle
Mastitis causing E coli- Cattle
MMA in pigs
UPEC- dogs
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

E. Coli: pigs

A 
ETEC- Diarrhea
VTEC-Oedema disease
EPEC
UTI
MMA
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

E. Coli: Cattle

A 
ETEC
Septicemia: NTEC
EPEC
EHEC/VTEC
Mastitis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

ETEC in piglets- adhesion factors

A 
Adhesion factor: F4
-Solely in pigs
-Neonatal to post weaning
F5
-Receptor only in very young animals: neonatal
F6
-Neonatal
F41
-Frequently together with F5
-Rare
-Neonatal
F18
-Oedema disease, from weaning on
Non-fimbrial adhesions
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

ETEC in piglets- Enterotoxins (on plasmids)

A
  1. Heat labile toxin (LT)
    - high molecular weight
    - strong antigen: vaccination
  2. Heat stable
    - STa, STb
    - EAST1 (enteroaggregative E coli heat stable toxin)
    - Low molecular weight
    - Little antigenic
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

ETEC in piglets- Virulence factors

A 
Age dependent importance
Neonatal ETEC
-F4; F5; F6; F41
-STa; STb
-Non hemolytic

Neonatal till 3 weeks

  • F4
  • LT; STa; STb; EAST1
  • Hemolytic

Post weaning diarrhea

  • F4; F18
  • LT; STa; STb; EAST1
  • Hemolytic
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

ETEC in piglets- Virulence and pathogenesis

A

In the intestine of healthy sows
Equilibrium between maternal immunity and infection pressure
Break in equilibrium=disease
-Increase infection pressure: low hygiene; presence of ETEC diseased piglets
-Lowering of maternal immunity
Sow: MMA (no milk); first delivery
Piglet: low birth weight; other infection
Too many piglets per sow
-Appearance of new type

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

ETEC in piglets: Piglet diarrhea

A

Distortion of equilibrium between immunity and microbial load: bacterial challenge too high and/or immunity too low (mainly maternal)

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

ETEC in piglets: Diagnosis

A

Symptoms and age:

  • remain drinking
  • v smelly feces
  • dehydration
  • Older piglets diarrhea (white, grey, not as watery)
  • Bacteriology + Detection of virulence factors
  • PCR
  • Agglutination
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

ETEC in piglets: Treatment

A

Hydration (SC, IP) (PO, electrolyte solution plus glucoses and amino acids)
Antimicrobials (susceptibility profile)

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

ETEC in piglets: Prevention

A

Hygiene and management: prevention of spread, cleaning and disinfection
Vaccination sows:
-Inactivated vaccines: different strains (with different F factors)
-Purified adhesion factors and LT
-Two injections of which the last one 2-6 weeks before partus
-Live vaccine
Vaccination of piglets (only of use for F4)
-Live vaccine for (post) weaning diarrhea
Selection of receptor free piglets (F4)

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

VTEC- Oedema disease in piglets: Virulence and pathogenesis

A
  1. Adhesion small bowl: F18
    - Specific receptor
    - Adhesion from approx of 10 days on
  2. Exotoxin
    - VT2e or Stx2e: media necrosis (blood vessels)
  3. Exotoxin: acute mortality

Oral intake of pathogenic E coli
Adherence and proliferation in intestine
Shiga toxin damages blood capillaries and increases fluid loss
Clinical Signs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

VTEC- Oedema disease in piglets: Virulence and pathogenesis

A 
Sow to piglet
Weaning: stress
-Change in intestinal flora
-Maternal immunity
Excretion -> infection pressure increase -> contamination other piglets
Toxin production: media necrosis
-Hyperacute: enterorhagia
-Acute: permeability blood vessels oedema (CNS and dyspnea)
-Slower: intravascular coagulation
Endotoxin: shock and acute mortality
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

VTEC- Oedema disease in piglets: diagnosis

A 
Symptoms: 
-<3 wks after weaning
-Multiple piglets affected
CS
Bacteriology and confirmation virulence factors
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

VTEC- Oedema disease in piglets: Clinical signs

A

Acute mortality (some)
Diarrhea (rare)
Anorexia
Oedema: hoarse voice, CNS, dyspnoea, swollen eyelids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

VTEC- Oedema disease in piglets: Treatment

A

Affected animals:
-fasting (elimination of toxin)
-Increase of intestinal peristaltic
-antimicrobial therapy (note: quite some resistance, susceptibility test)
Not yet affected animals
-antimicrobial therapy: incubation time of toxin 2-3 days (so you may still see symptoms after tx)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

VTEC- Oedema disease in piglets: Prevention

A

Reduce stress at weaning (no castration, no vaccination, keep temp constant)
Feed composition: feed restriction; increase fiber content; starter feed before weaning
Adaptation of intestinal flora (reduction of E coli and toxin): probiotics; organic acids (have antibacterial effects); Zin oxide (in feed for first 14 days after weaning)
Antimicrobials
Vaccination in piglets at age of 2-4 days (live vxn contains recombinant VT2e)
Selection of receptor F18 negative animals

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

EPEC diarrhea in piglets: virulence and pathogenesis

A

Rarer, little known about its general role
Diarrhea at weaning
Virulence factors:
-BFP- bundle forming pilli, initial attachment
-Attaching and effacing- intimate attachment
-eae
-T3SS (needle) and injection of effector proteins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

EPEC diarrhea in piglets: diagnosis

A

Bacterial isolation and detection of eae gene

27
Q

EPEC diarrhea in piglets: treatment

A

Antimicrobials (oral)

28
Q

EPEC diarrhea in piglets: Prevention

A

No vaccine

Little is known

29
Q

E coli- UTI in pigs

A

Most important pathogen in UTI in pigs
Other bacteria can be involved too
Originated most probably from intestine
Virulence factors E coli infection in pigs?
Predisposing factors: hygiene, water intake, obstipation, age, individual (anatomical) differences

30
Q

E coli- UTI in pigs: Diagnosis

A

Symptoms: Anorexia; Hematuria; Vaginal exudate; General malase
Bacteriology

31
Q

E coli- UTI in pigs: treatment

A

Culling (fertility problems)

Antibiotics approx 3 wks

32
Q

E coli disease in pigs: MMA or PPDS

A 
MMA= Metritis-mastits-agalactiae = no milk
PPDS= post partum Dysgalactiae Syndrome
Etiology
-hereditary
-hormonal
-feed
-Infectious agents
33
Q

E coli disease in pigs: Septicemia

A

Secondary to enteric infection

Rarely primary

34
Q

E coli in bovines

A 
ETEC: less than 3 d old
EPED: older than 1 wk
EHEC: zoonotic importance
Septicemic (NTEC): neonates, lack of colostrum
Mastitis
35
Q

ETEC in bovines: Virulence and pathogenesis

A 
Similar to pigs but:
Animals less than 3 d old
Adhesion: fimbriae
  -F5 (most common)
  -F41 (freq together with F5)
  -F17 (role not clear) (a,b freq assocaited with CNF2) (c with CS31A)
  -CS31A (related to F4) Freq relation to diarrhea in older animals
Toxins: Sta and Stb

Equilibrium between immunity and infection pressure
Colostrum: too little too late too low in Ab
Infection: too early, too high (infection pressure)

36
Q

ETEC in bovines: Diagnosis

A

ELISA

Culture and virulence gene detection: Agglutination/PCR

37
Q

ETEC in bovines: Therapy

A 
Separate sick animals
Hydration
Antibiotics: note- extremely high levels of acquired resistance
  -Diarrhea + fever: parenteral therapy 
  -No fever: oral therapy
NSAID (shock)
38
Q

ETEC in bovines: Therapy on milking farms

A 
Hygiene: separate calves from mothers
Colostrum: of multi-parturiant animals
Antibiotics p.o (4-5d)
Vaccination of cows
Antibodies p.o
39
Q

EPEC in bovines

A

Not a common infection
Virulence: eae
-cfr pigs, different strains but same virulence and pathogenesis mechanism

40
Q

EPEC in bovines: symptoms

A

Age: 1-8 wks
Mucoid diarrhea +/- blood
Mainly in large intestine

41
Q

EPEC in bovines: therapy

A

Antibiotics

42
Q

STEC/VTEC/EHEC in bovines

A

Only Zoonotic importance
Virulence genes: eae+stx1 and/or stx2
Specific serotypes
Responsible for serious infections with mortality (5-7%) and persistent lesions to kidneys
Also names Hemorrhagic Uremic Syndrome (HUS)

43
Q

NTEC in bovines: virulence

A 
ExPEC
Facultative pathogenic (freq in intestinal tract)
Virulence factors: serum resistance
-iron uptake systems
-endotoxin
-capsule
-adhesion factors (P, F17, AfaE-VIII, CS31A)
-CNF1, CNF2 (cytotoxic necrotic factor)
44
Q

NTEC in bovines: Pathogenesis

A

Uptake: per os OR umbilical cord
via lymphoid tissues of head and throat OR intestine
Septicemia
Hyperacute: acute mortality, shock
Acute: general symptoms, fast mortality
Slower with organ localization, poly arthritis, pneumonia, pleuritis, menigo-encephalitis

45
Q

NTEC in bovines: Diagnosis

A

Clinical (age, symptoms, colostrum: low gamma globulins in serum)
Isolation + PCR for virulence genes

46
Q

NTEC in bovines: Therapy

A

NSAID (shock)
Antibiotics (susceptibility testing)
Gamma globulins: plasma from older animals

47
Q

NTEC in bovines: Prevention

A

Make sure that the calves get good quality colostrum

48
Q

E coli Mastitis in bovines

A 
No virulence factors known
Environmental origin
DD gram +/ gram - infection: 
  -Gram -: with fever
  -Frequently lost udder quarter
Prevention: hygiene
Treatment: systemic antibiotics
49
Q

E coli disease in cats and dogs: enteric

A

Isolation from feces: significance???
Dogs: freq + other pathogens
-ETEC, EPEC, VTEC, EIEC: both in clinically healthy as well as diarrheic
Cat???

50
Q

E coli disease in cats and dogs: Cystitis- dog

A

UTI
Fimbriae: type one, F12, F13, associated with human UTI
Specific serotypes (O2, O4, O6, O83)
50% a-hemolytic

51
Q

E coli disease in cats and dogs: Cystitis- cat

A

Seldom (high osmolarity of urine is antibacterial)

52
Q

E coli disease in cats and dogs: cystitis- treatment

A

Check for underlying causes (bladder stone, tumor)

In general, broad spectrum antibiotics

53
Q

E coli disease in cats and dogs: pyometra

A

Dog- same strains as cystitis

Treatment frequently surgery and antibiotics

54
Q

E coli disease in poultry and other birds: APEC

A

Most important bacterial disease in broilers and layers
Facultative pathogen- normal e coli flora contains approx 10% pathogenic serotypes
Extra-intestinal disease: septicemia-colibacillosis

55
Q

E coli disease in poultry and other birds: APEC- virulence

A

Specific serotypes- most frequent: O1, O2, O78
Virulence factors- not understood what is important
-fimbriae/pilli
-iron capturing systems
-serum resistance

56
Q

E coli disease in poultry and other birds: APEC- pathogenesis

A

Different clinical appearances represent a different pathogenesis
Clinical appearances:
-Neonatal colibacillosis (septicemia)
-Respiratory colibacillosis and septicemia
-egg yolk peritonitis (layers)
-Scabby hip/necrotic dermatitis (broilers)
Coli granuloma (old backyard chickens)
Otitis media (part of swollen head syndrome)
Chronic respiratory colibacillosis + arthritis

57
Q

APEC: neonatal colibacillosis, pathogenesis

A

Contamination of eggshell
Neonatal contamination
Manipulation of chicks

Upon cooling after lay: shrinking of content
Yolk rest infection (omphalitis)
Sepsis -> death
Polyserositis, Airsac, Pericard -> growth retardation

58
Q

APEC: respiratory colibacillosis, Pathogenesis

A

Excretion via feces
Increase of inection pressure- dust has Ecoli
Inhalation of pathogenic e coli
Damage respiratory epithelium: dust, viral infection, vxn, NH3

59
Q

APEC: egg yolk peritonitis, pathogenesis

A

Endogenic infection
Start of lay
Chronic form in older animals

60
Q

APEC: scabby hip/ necrotic dermatitis

A 
E coli O78, O2
Frequently also other bacteria
Exogenous
Difficult to diagnose- feathers
Found at slaughter
Prevention- lower density of animals
61
Q

APEC: diagnosis

A 
Pathological lesions
Isolated of ecoli from different internal organs (liver, spleen, lung)
Serotyping (O1, O2, O78)
Yolk rest infection
Acute sepsis
Coligranuloma
Airsacculitis
62
Q

APEC: treatment

A

Very difficult

Antibiotics: susceptibility tests necessary

63
Q

APEC: prevention

A

Hygiene
Stress
Temp/ventillation
Vaccine- for breeding stock immunization, broilers and layers

64
Q

Ecoli diarrhea in rabbits: RPEC

A 
EPEC (eae positive)
Diagnosis: CS
  -Isolation and subtyping (necessary): bio-/serogroup (1+/O109) is mainly pathogenic to suckling rabbits; others are pathogenic to weaned rabbits
  -PCR on eae
Tx: antibiotics care! toxicity

Bacteriology (12 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions