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Streptococcaceae II Jeanne Filbey MT(ASCP)
Division of Medical Technology Student Laboratory
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Streptococcus viridans group
Alpha-hemolytic streptococci Streptococcus viridans group Colony morphology Tiny, gray, domed, alpha hemolysis Optochin/Taxo P resistant Bile solubility negative Bile esculin negative No growth in 6.5% NaCl
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Streptococcus viridans group
Alpha-hemolytic streptococci Streptococcus viridans group Clinical significance Normal flora Generally non-pathogenic Subacute bacterial endocarditis (#1 cause) Liver abscesses, bacteremia Streptococcus anginosus/milleri group Deep wound infections
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Abiotrophia species Nutritionally variant streptococci
Alpha-hemolytic streptococci Abiotrophia species Nutritionally variant streptococci Requires Vitamin B6 / pyridoxal to grow Clinical significance Normal flora Endocarditis
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How can you differentiate Streptococcus pneumoniae from Streptococcus viridans group?
Susceptibility to Optochin and bile solubility. Streptococcus pneumoniae is optochin sensitive and bile solubility positive. Streptococcus viridans group is optochin resistant and bile solubility negative.
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Streptococcus viridans group are clinically significant for what disease?
Subacute bacterial endocarditis (#1 cause)
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Abiotrophia species are clinically significant for what disease?
Subacute bacterial endocarditis
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Gemella species Colony morphology Gram stain: GPC in pairs and chains
Streptococcus-like bacteria Gemella species Colony morphology Resemble Streptococcus viridans group Can be alpha or gamma hemolytic Gram stain: GPC in pairs and chains Easily decolorized Pairs may have adjacent sides flattened
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Gemella species Identification Streptococcus-like bacteria
PYR variable Vancomycin sensitive Glucose non âFâ Bile esculin negative No growth in 6.5% NaCl
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Gemella species Clinical significance Streptococcus-like bacteria
Normal flora of respiratory and GI tracts Rarely isolated from humans Opportunistic pathogen Septicemia Wounds, abscesses Respiratory UTI
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Leuconostoc species Colony morphology
Streptococcus-like bacteria Leuconostoc species Colony morphology Resemble Streptococcus viridans group Can be alpha or gamma hemolytic Gram stain: GPC in pairs and chains Can be coccobacilli in appearance
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Leuconostoc species Identification Streptococcus-like bacteria
PYR negative Vancomycin resistant Glucose âFâ Bile esculin positive Variable growth / no growth in 6.5% NaCl
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Leuconostoc species Clinical significance Streptococcus-like bacteria
Normally found in environment Opportunistic pathogen in immunosuppressed patients Septicemia Wounds CSF
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Pediococcus species Colony morphology
Streptococcus-like bacteria Pediococcus species Colony morphology Resemble Streptococcus viridans group Can be alpha or gamma hemolytic Gram stain: GPC in pairs, tetrads and clusters
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Pediococcus species Identification Streptococcus-like bacteria
PYR negative Vancomycin resistant Glucose âFâ Bile esculin positive Variable growth / no growth in 6.5% NaCl Group D antigen positive
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Pediococcus species Clinical significance Streptococcus-like bacteria
Normally found in environment Opportunistic pathogen in immunosuppressed patients Blood Saliva Stool Urine Wounds
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How can you differentiate Gemella, Leuconostoc and Pediococcus from each other?
Biochem: G.S. PYR Van Gluc BE 6.5NaCl Gemella Pair, chain Variable Sensitive Non âFâ Negative No growth Leuconostoc Resistant âFâ Positive Pediococcus Tetrad, cluster Type Grp D
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Summary⌠Classification â hemolysis, C-substrate
Gram stain â GPC in pairs & chains Identification Beta Strep (PYR, Taxo A, SXT, Na hipp) Alpha Strep (Optochin, bile solubility) Gamma Strep (PYR, BE, 6.5% NaCl) Strep-like organisms Clinical significance of each organism
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Who am I? Gram stain BAP PYR Enterococcus species
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Streptococcus pyogenes
Who am I? Gram stain BAP PYR Streptococcus pyogenes
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Streptococcus pneumoniae
Who am I? Gram stain BAP with optochin Streptococcus pneumoniae
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Streptococcus agalactiae
Who am I? PYR Na hippurate Gram stain BAP Streptococcus agalactiae
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