Escherichia Coli Flashcards Preview

Alimentary > Escherichia Coli > Flashcards

Flashcards in Escherichia Coli Deck (10):
1

E.coli

normal inhabitant of colon
extraintestinal infection (colisepticaemia)
enteric disease (special strains - ETEC)
public health (rare, special strains - ETEC)

2

Enterotoxigenic Escherichia coli (ETEC)

watery diarrhoea - scours
enterotoxigenic
small intestine

3

ETEC in calves, piglets, lambs

neonatal enteritis
ingestion - colonisation of lower SI
diarrhoea + stunting of villi
often with rotavirus

4

2 ETEC factors for infection

adhesive fimbrae - colonisation
enterotoxin

5

labile toxin (LT)

similar to cholera toxin
attaches to brush border of SI
incr cAMP, Cl- secretion - NA+ + water lost into lumen
metabolic acidosis, dehydration, electrolyte loss
can be fatal

6

stable toxin (ST)

raises intracellular guanylate cyclase

7

ETEC - diagnosis

on clinical grounds
faecal culture always shows e.coli
need to show toxin + fimbriae

8

STEC

shiga-toxin producing e.coli
toxins ST-1 + ST-2
some diarrhoea + haemorrhagic colitis in calves

9

STEC - public health

carriage by calves - beef
v.low dose infects humans
cooking destroys the pathogen

10

STEC - human disease

haemorrhagic colitis + haemolytic uraemic syndrome - renal failure
vascular damage, oedema, thrombi
thrombotic thrombocytopaenic purpurea