Bacteriology 9: Gram - enteric bacteria Flashcards
Will you see gram - cocci ?
NO
Gram - are what morphology?
Rods
What are the families of bacteria?
Enterobacterales
Pasteurellaceae
Misellanious
Enterbacterales are oxidase poisitive or negative?
Negative (-)
How many generas do Enterbacterales have?
50
we focus on 5
-escerichia
-salmonella
-Yersinia
-Klebsiella pneumoniae
-Proteus
Shared features of Enterbacterales?
gram -
faculatatively anaerobic
oxidase negative
MOTILE (virulence factor)
similar colonies in BLOOD agar
grow on MACCONKEY’S AGAR
-tolerate bile salts
-lactose ferm is variable
How do you separate Lactose fermentation?
+ =
E.coli
Klebsiella
-=
Proteus
Salmonella
Yersinia
Are all Enterbacterales the same pathogenicity?
No
What is the differential diagnosis list?
VINDICATE
V=vascular
I=infection
N=neoplasia
D= degeneration
I= inflammation
C= congenital
A=autoimmune
T=Trauma
E= endocrine
Ecoli in our case caused what kind of disease?
Pyometra
In our case the uterus was infected what kind of site is this?
Sterile site
4pt rule:
-sample collected correctly
-evidence of inflammation (many neutrophils-left-shift)
-evidence of bacteria
-did the bacteria have the OPPORTUNITY and the ABILITY to cause the disease
E. coli comes from where?
Normal flora in GI tract
-ilium and LI
one of first organism in neonatal GIT w/n hours
Survive well in environment
-COLIFORM good indicators in environment (water and soil, etc.)
E.coli transmission occurs how?
Depends on site of infection:
- fecal oral
-inhalation
-direct inoculation
-ascending infectiosn
–cystitis
–pyometra
–transient in Uro. tract
E.coli key point is?
VERY diverse
NOT all strain of this disease are virulent
How does E.coli cause disease?
Strain with virulence factors
-attachment
-avoidance of phagocytosis
-cellular effects
-systemic effects
Contribution of virulence factor depends on SITE OF INFECTION
