Staph/Strep
Terms
undefined, object
copy deck
- family/genus/species of staph:
-
micrococcaceae
staphylococcus
aureus, epidermidis, saprophyticus, +13 - gram stain of staph
- nice round gram positive cocci in clusters
- catalase test for staph shows
- positive
-
growth requirement of Staph
type of respiration -
none/ not fastidious
facultative anaerobe - grows anywhere - colonial morphology of all staph species
- white, round, creamy, opaque, convex, large with prolonged incubation
- coag test for staph
- positive; if slide shows positive you're good.
- principle of coag test
- first do slide test for bound coag; if negative, then do a tube test for free
- pigmentation of staph aureus vs. epi
- aureus = yellow, epi = white
- hemolytic rxtns of aureus vs. epi
-
aureus = beta
epider = gamma - principle of latex agglutination test
-
latex beads coated with
-latex
-anti-protein A
bugs that produce coagulase will bind beads.
bugs that have protein A (s aureus does) will bind Ab. - alternative tests for I.D. of aureus or epi
-
latex agglutination
DNAse or Thermostable Nuclease
Mannitol salt
Novobiocin - principle of novibiocin test
- saprophyticus is resistant, other species of staph are not
- what type of specimen is mannitol salt for
-
stools
shows fermentors - s. aureus
shows growth if able to grow on salt - s. aureus is - diseases caused by s. epi and other coag neg staphs
-
-bacterial endocarditis of prosthetic valve
-surgical prosthesis infection
-bacteremia - disease caused by s. saprophyticus
- URINARY TRACT INFECTION
- 6 extracellular substances produced by s. aureus
-
exfoliative toxin (gets under epidermis)
leukocidin (kills WBC)
enterotoxin (causes 1/3 of food poison)
coagulase (fibrin walls off from immun)
protein A (allows resist to phagocytos)
others (v. virulent) - diseases of skin caused by s. aureus
-
pimples/acne/folliculitis
carbuncles
boils/furuncles
impetigo
cellulitis
scalded skin syndrome - ritters disease
- caused by s. aureus; also known as scalded skin syndrome; in infants, bacteria under epidermis cleaves skin off
-
diseases of digestive tract caused by s. aureus
what toxins?
charact: length, symptoms, causes -
food poisoning
Enterotoxins A and D
2-6 hr incub., nausea/vomit/diahhr., unrefrig high protein foods
self limiting - respiratory disease caused by s. aureus
- pneumoniae; yellow sputum
-
tampons + s. aureus =
caused by -
toxic shock syndrome
tsst-1
initial - high fever, dizzy, vomit, shock
2 days later - sunburn rash, hypotens. - staph does what to bones
- causes osteomyelitis
-
when is an epidemiological investigation conducted?
what is it - outbreak;phage typing nad plasmid analysis
- phage typing
- a plate has different phages which infect various bacteria; if the same spot on two plates shows no growth, the bacteria are the same.
- what does s. aureus produce, and therefore you can't prescribe
- b-lactamase; penicillins or cephalosporins
- use to treat s. aureus: (simple)
- methicillin
- to treat MRSA
-
vancomycin
its due to PBPs