Enteric Bacteria (2) Flashcards
salmonella gram stain & shape motile? lactose fermenter? oxidase +/- urease +/- H2S +/-
gram negative rod motile seldom lactose fermenter oxidase - urease - H2S +
what are the 2 types of salmonella that are usually the cause of enteric fever
salmonella typhi and salmonella paratyphi
how does salmonella typhi/paratyphi spread to major organs
via lymphatics in a trojen horse
tell me about the presentation of the enterocolitis in salmonella
non bloody diarrhea, fever, dehydration
tell me about the presentation of the enteric fever in salmonella
high fever, headache, tender abdomen, anorexia, lethargy sometimes rose spots
Y. enterocolitica and Y. pseudotuberculosis: gram stain and shape lactose fermenter? urease +/- motile?
gram - oval rods
non lactose fermenting
urease positive
motile at 25C and nonmotile at 37C
what disease does Y. enterocolitica cause
entercolitis
how does Y. enterocolitica carry its virulence factors
on chromosome and plasmid
what pathogen can cause a “false apendicitis”
Y. enterocoliticia
high or low infectious dose with Y. enterocolitica enterocolitis
high infectious dose
can Y. enterocolitica cause reactive arthritis
yes
what disease can Y. pseudotuberculosis in children
Izumi fever
what is the presentation of entercolitis with Y. enterocolitica or Y. pseudotuberculous
diarrhea, dehydration, false appendicitis
listeria monocytogenes:
gram stain and shape
motile?
hemolysis?
gram + rod
tumbling motility
beta hemolytic
what are 4 ways that humans contract listeria?
unpasteurized dairy
undercooked meat
raw veggies
contact with livestock and manure
what organism has the internalin virulence factor and what does it do?
listeria. binds host E-cadherin, mediates invasion of cells in GI tract, placenta, meningitis
what organism has the listeriolysin virulence factor and what does it do?
listeria. opens phagosome and bacteria escapes into cytosol
what organism has the ActA virulence factor and what does it do?
listeria. allows for cell cell spread by polymerizing the host actin into rockets
what can a listeria infection during prego cause
abortion, premature delivery, post partum sepsis
what does listeria cause in a newborn
meningitis
what does listeria cause in a previous healthy person
gastroenteritis: watery diarrhea, fever, HA, myalgias, abdominal cramps, little vomiting
how does listeria appear on culture
small gray beta hemolytic colonies confirmed by motility, sugar fermentation
