enterobacterales Flashcards
enterobacterales are gram ___ and what shape?
negative; short straight rods (bacilli)
which enterobacterales are lactose fermenting
klebsiella, e coli
types of typhoidal salmonella
S. typhi, S. paratyphi
what does typhoidal salmonella cause
enteric fever
where does typhoidal salmonella occur
developing countries
role of antibiotics with typhoidal salmonella
decrease mortality and morbidity
is there a carrier state with typhoidal salmonella
yes, for up to a year or more
what are the reservoirs for non-typhoidal salmonella
animal and human
where does non-typhoidal salmonella occur
developed and non developed countries
what does non-typhoidal salmonella cause
gastroenteritis (diarrhea)
role of antibiotics in non-typhoidal salmonella
may prolong carriage
is there a carrier state with non-typhoidal salmonella
uncommon
what are the types of non-typhoidal salmonella
S. enteritidis and S. typhimurium
what are the types of shigella
S. dysenteriae, S. flexneri, S. boydii, S. sonnei
which shigella produces an exotoxin like shiga toxin
S. dysenteriae
which shigella is common in the US
S. sonnei
how can shigella be spread
fecal oral and person to person because it is easily transmissible due to a low inoculum
role of antibiotics in shigella
shorten fecal shedding
reservoirs for entero-associated e coli
human and animal
what is the strain of EHEC that causes HES
O157:H7 (STEC)
what are contraindications for EHEC, STEC
antimotility agents are contraindicated, antibiotics are controversial but generally avoid.
which e coli is infantile diarrhea
EPEC
Which e coli is main cause of travelers diarrhea
ETEC
what does uropathogenic e coli cause
most common cause of UTI. also bacteremia-sepsis and neonatal meningitis
types of klebsiella
K. pneumoniae and K. oxytoca
klebsiella pneumoniae causes
community: CAP, UTI
klebsiella oxytoca causes
UTI
all klebsiella strains are resistant to
ampicillin, amoxicillin, penicillin (inherent)
types of proteus
mirabilis, vulgaris
what does proteus do
hydrolyzes urea to form kidney stones, associated with UTIs
proteus has inherent resistance to
nitrofurantoin and tetracyclines
serogroups of vibrio cholerae
O1, O39
shape, type of bacteria is vibrio
gram (-) curved rod shaped like a comma, facultative anaerobe
vibrio cholerae produces
exotoxin (cholera toxin, endotoxin)
all vibrio require __ for growth
salt
how is vibrio cholerae transmitted
fecal-oral, requires large inoculum
vibrio cholerae reservoirs
animal, water
what does vibrio cholerae cause
watery, rice water diarrhea, can be fatal in 24 hours, massive fluid loss (cholera cot)
what is vibrio parahaemolyticus associated with
contaminated raw shellfish, seafood-associated gastroenteritis
which straight rods/bacilli are facultative anaerobes
enterobacterales fam: e. coli, klebsiella, proteus, salmonella, shigella
which straight rods/bacilli are aerobes
legionella pneumophilia
which straight rods/bacilli are anaerobes
fusobacterium, prevotella, bacteroides
which rods/bacilli are curved
vibrio, campylobacter
which aerobic diplococci are spherical
neisseriae family
which pleomorphic cocco bacilli are aerobes
bordetella, haemophilus influenzae, moraxella catarrhalis
what is a helical/spherical bacteria
helicobacter pylori
salmonella is oxidase ____
negative
what are the 2 main salmonella species
bongori, enterica
what is the common salmonella species
enterica
Salmonella typhi, paratyphi, enteritidis, and typhimurium are the ____
SEROTYPES/serovars
what does the kauffman white classification differentiate
isolates of a given serotype by determining the major antigens: important for tracking outbreaks to their source
what is the O antigen
lipopolysaccharide (LPS)
what is the H antigen
flagella
what is the Vi antigen/K antigen
bacterial capsule
what is the reservoir for typhoidal salmonella
only humans
how is typhoidal salmonella acquired
ingestion of fecally contaminated food/water
how can non-typhoidal salmonella be transmitted
uncooked/undercooked poultry and eggs, pet reptiles, contaminated marijuana, fecal-oral
shigella is oxidase ____
negative
shigella disease and reservoir is limited to ____
humans
how does shigella invade
cross mucosa via M cells, use invasins to enter epithelial cells,move thru host cell and spread to adjacent host cells via actin based motility
does e coli ferment lactose
yes
which e coli groups are small intestine
EAEC, EPEC, ETEC
which e coli groups are large intestine/colon
EHEC, EIEC
what is the pathogenesis of EAEC
adheres to intestinal cells (Stacked bricks), produce mucus and biofilm, cytotoxin damages intestines
what is the major etiologic agent of hemorrhagic colitis and HUS
O157:H7 (STEC)
STEC is also known as
VTEC (verocytoxin EC)
what is HUS
hemolytic uremic syndrome: a triad of microangiopathic hemolytic anemia, thrombocytopenia, acute renal failure
what is EIEC related to
Shigella: causes shigella like dysentery; invades and destroys colonic epithelium
what causes outbreaks of ETEC
food/water contamination: a high inoculum is required, so no person to person spread
what do klebsiella produce
highly mucoid colonies due to luxuriant polysaccharide capsule
which bacteria swarm over a moist agar plate
proteus
proteus have ____ that aid in colonizing the urinary tract
fimbriae/pili
what are the parts of a gram (-) cell wall
outer membrane, periplasmic space containing a thin peptidoglycan layer, cytoplasmic membrane, pili/fimbriae and flagella structures
ESBL is most prevalent in which organisms
e coli, klebsiella (pneumoniae and oxytoca), proteus mirabilis