Gram positive Cocci, Quiz 3

Staph and strep bugs!

The only white blood cell reported in micro is

Neutrophils

The only other cell besides bacteria and neutrophils that are reported is

squamous epithelial cells

Impetigo is caused by

• S. aureus

• group A strep

Enterotoxins

food poisoning

TSST-1

toxic shock

Exfoliative Toxin

scalded skin syndrome

Cytologic toxins

emolysins and leukocidin

S. aureus

• creamy yellow colonies, beta hemolytic

S. aureus uses what carbs

• mannitol

• dextrose

s. aureus is coag __ and catalase _

• +

• +

Coagulase-Negative Staph

• Catalase positive
• Coagulase negative
• Carbohydrates

• Mannitol – neg.

• Dextrose – pos.

Staph saprophyticus

novobiocin R

Cefoxitin susceptibility means what other antibiotics are S

• not reported

• suceptible reading= S to Oxacillin and Cefazolin

D-Zone test

• Erythromicin has to be resitant

• Erythromicin induces clindamycin to become resitant, creates a D shape

Micrococcus

• coag negative

• mannitol and dextrose negative

• oxidase positive

• tetrads

Beta hemolytic strep is differentiated by

• lance field antigens

rheumatic fever

• Fever, inflammation of the heart, joints, blood
  vessels and subcutaneous tissues

• Cross reaction of antibodies produced against
  strep with host tissues (autoimmune)

rheumatic fever caused by

group A strep

Acute, poststreptococcal glomerulonephritis

• Impairment of kidney function

• Antigen/antibody complexes

• After infection

Acute, poststreptococcal glomerulonephritis caused by

group A strep

group A M Protein

• chief virulence factor, helps resist
  phagocytosis and helps adhere to mucosal cells

Streptolysin O

Oxygen liable hemolysin

Streptolysin S

oxygen stable hemolysin

Group B strep camp test forms what shape

arrow

Sodium Hippurate Hydrolysis group B turns what color

purple

Streptococcus pneumoniae

• Oropharyngeal carriage is common

• Most common cause of bacterial meningitis in
  adults

• Most common cause of community-acquired
  pneumonia with or without bacteremia

• Endocarditis

• Sinusitis & otitis media

Streptococcus pneumoniae look like

• ants without legs, pairs or short chains

• lancet shapes

• encapsulate

Enterococcous

• weak catalase

• PYR+

• grows in 6.5% NaCl

• Bile esculin +

screening for VRE uses

vancomycin disk

E. faecium & E. faecalis are the most common clinical isolates with acquired

high level resistance

Group a and Group B is penicilin Susceptible, how do you test

E TEST ONLY

bacitracin is susceptible for

S. Pyogenes

aerococcous looks like a _______ on a gram stain

staphylococcus

HLAR and GM120 used to check for

synergy affect against amino glycosides and cell wall inhibitors

all streps are predictably susceptible to Penicilin but what test do you confirm

E test

if catalase is positive but coag is negative for a s. aureus what is the next step

tube coag

blood agar plate, clear skim milk colonies, likely

group B strep

test for catalase, hippurate, streptex, camp positive(arrow)

neonatal GBS is key, as it shows up in what period of time?

10 days to 6months

lance field antigens are made of

cell wall polysacharides

what testis the fastest to tell the difference between S. viridians and S. pneumo?

Bile solubility (s. Pneumo is +)

rabbit plasma detects

tests for clumping factor

steptaurex detects

clumping factor and Protein A

tube coag detects

free coagulase and bound factors

staphaurex uses what to detect coagulase factors

Latex particles coated with fibrinogen and IgG

if kirby baer disk test for strep is Intermediate for vancomycin you have to follow up with a

E test