Escherichia, shigella, citrobacter

What are the four common infections from E. coli?

UTI, gastroenteritis, neonatal meningitis, septicemia

What is the capsule symbol for E. coli?

K1

What are the four virulence factors of E. coli?

pili, cytolysins, aerobactin, exotoxins

On MAC agar, what color colonies do we see for E. coli and what kind of precipitate forms?

Pink colonies, bile precipitates

In general, E. coli can ferment _______ and _________.

lactose, sucrose

Which of the E. coli pathogens is lactose negative, nonmotile, and LDC negative?

EIEC

Which of the E. coli pathogens is sorbitol negative and MUG negative?

EHEC (O157:H7)

What disease does ETEC cause?

travelers diarrhea, watery stool

What disease does EIEC cause?

dysentery, bloody stool

What disease does EPEC cause?

infantile diarrhea, mucus

What disease does EHEC cause?

hemorrhagic diarrhea, HUS, bloody stool

What diseases does DAEC cause?

cystitis, UTI, pediatric diarrhea

Which E. coli strain has shiga-like toxin?

EHEC

Which strain of E. coli has LT and ST toxins?

ETEC

What is the IMViC of E. coli?

PPNN

What is the TSI rxn for E. coli?

A/A

What is the IMViC for citrobacter freundii?

NPNP

What diseases does citrobacter cause?

nosocomial UTIs, abscesses, and pneumonia

What is the IMViC for citrobacter koseri?

PPNP

What is the TSI rxn for citrobacter freundii?

A/A

What is the TSI rxn for citrobacter koseri?

K/A

Can citrobacter produce H2S gas?

yes, variable

What is the characteristic biochemical test that can identify the genus citrobacter?

SLOW urease positive

What is the IMViC for shigella sonnei?

NPNN

What kind of motility does shigella have?

non-motile

What characteristic biochemical test can identify shigella?

slow lactose fermentation

What disease does shigella cause?

bacterial dysentery with blood, pus stools

Which serogroup of shigella is most common in the US?

D

What kind of infective dose is needed for a shigella infection?

Low