aureus epidermidis nonhem olytic usua lly epidermidis epidermidis
•
major component skin flora major component skin flora
•
opportunistic infections opportunistic infections
–
less common than less common than
S.aureus S.aureus
•
nosocomial infections nosocomial infections
–
heart valves heart valves
•
Identification Identification
–
Non-hemolytic Non-hemolytic
sheep blood agar sheep blood agar
–
Does not ferment mannitol Does not ferment mannitol
–
Non-pigmented Non-pigmented
–
Coagulase-negative Coagulase-negative
Staphylococcus saprophyticus Staphylococcus saprophyticus
•
urinary tract infections urinary tract infections
•
coagulase-negative coagulase-negative
–
not differentiated from not differentiated from
S. epidermidis S. epidermidis
The Streptococcus
Streptococcus
Morphology Identification
•
facultative anaerobe facultative anaerobe
•
Gram-positive Gram-positive
•
Chains Chains
or pairs or pairs
•
Catalase Catalase
negative negative
staphylococci are catalase positive staphylococci are catalase positive
Cell surface structure of S pyogenes and extracellular substances
•
Lancefield groups Lancefield groups
one or more species per group one or more species per group
surface antigens: M, T, R surface antigens: M, T, R
groupable streptococci
streptococci
•
A, B and D A, B and D
–
most important most important
• C, G, F