P2 MICROBIOLOGY Flashcards
Campylobacter like organisms
Helicobacter pylori
shape of H.pylori
spiral shaped
H.PYLORI causes
Gastritis , peptic ulcer, stomach cancer , MALT
Characteristics of H.pylori
gram negative
spiral shaped
Highly motile with lopotrichus flagella
microaerophilic
urease +
what dose microaerophilic
Require little CO2
meaning of urease +
converts urea to ammonia
produces urea as well
Transmission of H.pylori
oral-oral
oral-fecal
what is a microaerophilic environment
5% O2 , 10% CO2 , 85% N2
Virulence factors in H.PYLORI
1-flagella
2-urease
3-toxins
4-adhesins
5-enzymes /lipopolysaccharides
ROLE OF flagella
Motility in mucus layer
role of urease
breakdown of urea into CO2 & ammonia
= neutralise acid
role of lipopolysaccharides
adhesion + damage to host cell
role of adhesions
hemagglutinins , sialic acid binding
role of CagA gene
remodel host cell , inhibit apoptosis
Production of IL-8
what cytokines increases gastrin release
TNF-ALPHA
IL-8
INF-1GAMMA `
TNF-ALPHA lowers D cells causing
to lower somatostatin levels
major location of H.pylori infection
antrum of the stomach
proximal , distal duodenum
Mention difference’s between H.pylori & Campylobacter
H.pylori : 1- multiple flagella
2- urease +
Campylobacter :1- single flagella
2- urease -
Invasive diagnosis tests done
rapid urease
direct microscopy
Histology , culture
non-invasive diagnosis tests done
urea breath test , IgG / IgA immunoglobulins , PCR , antigens in stool
in CLO test we are looking for colour change form
Yellow to red/magneta
Yellow to red change in color indicates
Urease is present
in culture , what agars do we prefer
skirrow/dent agars
blood / chocolate agars
blood / chocolate agars are what type of agars
non selective
