Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Bacteriology > Enterobacteriaceae- E coli > Flashcards

Enterobacteriaceae- E coli Flashcards

(64 cards)

Start Studying
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
EPEC diarrhea in piglets: virulence and pathogenesis
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
26
EPEC diarrhea in piglets: diagnosis
Bacterial isolation and detection of eae gene
27
EPEC diarrhea in piglets: treatment
Antimicrobials (oral)
28
EPEC diarrhea in piglets: Prevention
No vaccine | Little is known
29
E coli- UTI in pigs
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
E coli- UTI in pigs: Diagnosis
Symptoms: Anorexia; Hematuria; Vaginal exudate; General malase Bacteriology
31
E coli- UTI in pigs: treatment
Culling (fertility problems) | Antibiotics approx 3 wks
32
E coli disease in pigs: MMA or PPDS
``` MMA= Metritis-mastits-agalactiae = no milk PPDS= post partum Dysgalactiae Syndrome Etiology -hereditary -hormonal -feed -Infectious agents ```
33
E coli disease in pigs: Septicemia
Secondary to enteric infection | Rarely primary
34
E coli in bovines
``` ETEC: less than 3 d old EPED: older than 1 wk EHEC: zoonotic importance Septicemic (NTEC): neonates, lack of colostrum Mastitis ```
35
ETEC in bovines: Virulence and pathogenesis
``` 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
ETEC in bovines: Diagnosis
ELISA | Culture and virulence gene detection: Agglutination/PCR
37
ETEC in bovines: Therapy
``` Separate sick animals Hydration Antibiotics: note- extremely high levels of acquired resistance -Diarrhea + fever: parenteral therapy -No fever: oral therapy NSAID (shock) ```
38
ETEC in bovines: Therapy on milking farms
``` Hygiene: separate calves from mothers Colostrum: of multi-parturiant animals Antibiotics p.o (4-5d) Vaccination of cows Antibodies p.o ```
39
EPEC in bovines
Not a common infection Virulence: eae -cfr pigs, different strains but same virulence and pathogenesis mechanism
40
EPEC in bovines: symptoms
Age: 1-8 wks Mucoid diarrhea +/- blood Mainly in large intestine
41
EPEC in bovines: therapy
Antibiotics
42
STEC/VTEC/EHEC in bovines
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
NTEC in bovines: virulence
``` 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
NTEC in bovines: Pathogenesis
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
NTEC in bovines: Diagnosis
Clinical (age, symptoms, colostrum: low gamma globulins in serum) Isolation + PCR for virulence genes
46
NTEC in bovines: Therapy
NSAID (shock) Antibiotics (susceptibility testing) Gamma globulins: plasma from older animals
47
NTEC in bovines: Prevention
Make sure that the calves get good quality colostrum
48
E coli Mastitis in bovines
``` No virulence factors known Environmental origin DD gram +/ gram - infection: -Gram -: with fever -Frequently lost udder quarter Prevention: hygiene Treatment: systemic antibiotics ```
49
E coli disease in cats and dogs: enteric
Isolation from feces: significance??? Dogs: freq + other pathogens -ETEC, EPEC, VTEC, EIEC: both in clinically healthy as well as diarrheic Cat???
50
E coli disease in cats and dogs: Cystitis- dog
UTI Fimbriae: type one, F12, F13, associated with human UTI Specific serotypes (O2, O4, O6, O83) 50% a-hemolytic
51
E coli disease in cats and dogs: Cystitis- cat
Seldom (high osmolarity of urine is antibacterial)
52
E coli disease in cats and dogs: cystitis- treatment
Check for underlying causes (bladder stone, tumor) | In general, broad spectrum antibiotics
53
E coli disease in cats and dogs: pyometra
Dog- same strains as cystitis | Treatment frequently surgery and antibiotics
54
E coli disease in poultry and other birds: APEC
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
E coli disease in poultry and other birds: APEC- virulence
Specific serotypes- most frequent: O1, O2, O78 Virulence factors- not understood what is important -fimbriae/pilli -iron capturing systems -serum resistance
56
E coli disease in poultry and other birds: APEC- pathogenesis
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
APEC: neonatal colibacillosis, pathogenesis
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
APEC: respiratory colibacillosis, Pathogenesis
Excretion via feces Increase of inection pressure- dust has Ecoli Inhalation of pathogenic e coli Damage respiratory epithelium: dust, viral infection, vxn, NH3
59
APEC: egg yolk peritonitis, pathogenesis
Endogenic infection Start of lay Chronic form in older animals
60
APEC: scabby hip/ necrotic dermatitis
``` E coli O78, O2 Frequently also other bacteria Exogenous Difficult to diagnose- feathers Found at slaughter Prevention- lower density of animals ```
61
APEC: diagnosis
``` Pathological lesions Isolated of ecoli from different internal organs (liver, spleen, lung) Serotyping (O1, O2, O78) Yolk rest infection Acute sepsis Coligranuloma Airsacculitis ```
62
APEC: treatment
Very difficult | Antibiotics: susceptibility tests necessary
63
APEC: prevention
Hygiene Stress Temp/ventillation Vaccine- for breeding stock immunization, broilers and layers
64
Ecoli diarrhea in rabbits: RPEC
``` 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