02 GRAM POSITIVE COCCI (Streptococcus & Related Organisms) Flashcards
Streptococcus and Enterococcus are from family ___
Streptococcaceae
based on oxygen requirement
Streptococcus and Enterococcus are ___
facultative anaerobes
give the result
Streptococcus and Enterococcus are catalase (_)
negative
Streptococcus and Enterococcus are susceptible to ___
Vancomycin
Streptococcus and Enterococcus require selective media such as ___ with antibiotics
BAP
Sherman’s classification
Grows at 37C; pus forming
Pyogenic
S. pyogenes
Sherman’s classification
Grows at 37C and 45C
Viridans
S. salivarius, S. mutans, S. mitis, S. sanguis
Sherman’s classification
Grows at 10C and 37C
Lactic
S. lactis
Sherman’s classification
Grows on dairy products
Lactic
S. lactis
Sherman’s classification
Grows at 10C, 37C, and 45C
Enterococcal
E. faecalis, E. faecium, E. durans, E. avium
Sherman’s classification
Part of the normal flora but can be opportunistic
Enterococcal
Rebecca Lancefield Classification
Cell wall polysaccharide
A, B, C, F, G
Rebecca Lancefield Classification
Cell wall teichoic acids
D and enterococcus
Not classified under Rebecca Lancefield Classification
- Viridans strep
- S. pneumoniae
has no carbon C carbohydrate
Brown’s classification (based on hemolytic pattern)
Beta hemolytic
- Grp A Strep
- Grp B Strep
- Grp C, F, G
S. pyogenes, S. agalactiae
Brown’s classification (based on hemolytic pattern)
Alpa hemolytic
- Viridans strep
- S. pneumoniae
Brown’s classification (based on hemolytic pattern)
Gamma hemolytic
- Grp D Strep
- Enterococcus
The visualization of alpha-prime hemolysis is enhanced with ___
refrigeration
Beta hemolysin
Oxygen labile and antigenic
Streptolysin O
causes subsurface hemolysis
Beta hemolysin
Oxygen stable; surface hemolysis
Streptolysin S
Rebecca Lancefield Classification
S. pyogenes
Grp A
Rebecca Lancefield Classification
S. agalactiae
Grp B
Rebecca Lancefield Classification
S. dysagalactiae
Grp C
Rebecca Lancefield Classification
S. equi
Grp C
Rebecca Lancefield Classification
S. bovis
Grp D
non-enterococcus member of viridans strep
Rebecca Lancefield Classification
E. faecalis, E. faecium
Grp D
Enterococcus
Rebecca Lancefield Classification
S. pneumoniae
Grp D
Pneumococcus
Rebecca Lancefield Classification
Anginosus group, mutans group, mitis group, salivarius group
Viridans strep
Rebecca Lancefield Classification
Causes rheumatic fever, scarlet fever, pharyngitis, glomerulonephrities, pyogenic infections
Grp A
S. pyogenes
Rebecca Lancefield Classification
Causes neonatal sepsis, meningitis, puerperal fever, pyogenic infections
Grp B
S. agalactiae
Rebecca Lancefield Classification
Causes pharyngitis, impetigo, pyogenic infections
Grp C
S. disagalactiae, S. equi
Rebecca Lancefield Classification
Causes endocarditis, UTIs, pyogenic infections
Grp D
S. bovis group
Rebecca Lancefield Classification
Causes UTIs, pyogenic infections, pneumonia, meningitis
Grp D
E. faecalis, E. faecium, S. pneumoniae
Rebecca Lancefield Classification
Causes pyogenic infections, endocarditis, dental caries, abscesses in various tissues
Viridans strep
Identify the Streptococcus spp.
Colonizes skin and throat
S. pyogenes
Virulence factor of S. pyogenes; associated with sequelae
M protein
present in the cell wall
Virulence factor that causes rheumatic heart disease and glomerulonephritis
M protein
M protein is coded by ___
EMM gene
Identify the Streptococcus spp.
Most common manifestation includes tonsilitis and pharyngitis
S. pyogenes
Identify the Streptococcus spp.
Causes “strep throat”
S. pyogenes
Identify the Streptococcus spp.
Associated with lymphadenopathy
S. pyogenes
The pyodermal infection caused by S. pyogenes produces ___ toxin
Erythogenic
The Erythogenic toxin is also known as ___
Scarlatina toxin/ Streptococcal pyogenic exotoxin
Pyodermal infection characterized by erythema and edema
Erysipelas
different from Erysipeloid caused by E. rhusiopathiae
Identify the Streptococcus spp.
Causes necrotizing fascitis; necrosis of skin, subcutaneous fat, and fascia
S. pyogenes
Streptococcal toxic shock syndrome is caused by ___
Pyogenic exotoxin A
Poststreptococcal sequelae include ___ and ___
- Acute rheumatic fever
- Acute glomerulonephritis
Postreptococcal sequelae
Characterized by fever, arthralgia, cardiac valvular disease
Acute rheumatic fever, Rheumatic heart disease
Postreptococcal sequelae
Characterized by edema, hypertension, hematuria, proteinuria, and RBC casts
Acute glomerulonephritis
DOC for Grp A Streptococcus infection
Penicilin or Erythromycin
Pathogenic determinant of Grp A Streptococcus (extracellular)
Antigenic; O2 labile
Streptolysin O
Pathogenic determinant of Grp A Streptococcus (extracellular)
Non-antigenic; O2 stable
Streptolysin S
Pathogenic determinant of Grp A Streptococcus (extracellular)
Causes fever, skin rash or scarlet fever, blood brain alteration, organ damage
Erythrogenic/ Pyogenic toxins A, B, C
Pathogenic determinant of Grp A Streptococcus (extracellular)
Protease implicated in flesh eating streptococci
Exotoxin B
Pathogenic determinant of Grp A Streptococcus (extracellular)
Lysis of blood clots; spread of infection
Streptokinase
Pathogenic determinant of Grp A Streptococcus (extracellular)
DNAse
Streptodornase
most common: DNAse B
Pathogenic determinant of Grp A Streptococcus (extracellular)
Induce proliferation of host T-lymphocytes
Superantigens
Pathogenic determinant of Grp A Streptococcus (cell surface antigen)
Mucoid colonies; antiphagocytic
- M protein
- Hyaluronidase
Pathogenic determinant of Grp A Streptococcus (cell surface antigen)
Spreading factor
Hyaluronidase
Pathogenic determinant of Grp A Streptococcus (cell surface antigen)
Mediates epithelial cell attachment
Protein F
Fibronectin binding protein
Identify the Streptococcus spp.
Cause of mastitis in cattle and invasive disease in newborns
S. agalactiae
Grp B Strep
Identify the Streptococcus spp.
Normal flora of GI tract, pharynx, and vaginal tract
S. agalactiae
Grp B Strep
DOC for Grp B Strep infections
Penicillin
Pathogenic determinant of Grp B Streptococcus
Sialic Acid
Capsule
Pathogenic determinant of Grp B Streptococcus
Promote/ enhance hemolysis
CAMP factors
Christie Atkins Munch-Petersen
Identify the Streptococcus Rebecca Lancefield Classification
Ability to grow in 40% bile and hydrolyze esculine
Grp D strep & Enterococcus
Identify the Streptococcus Rebecca Lancefield Classification
Gr (+) cocci that are nomal flora of GI tract of animals and humans; produce Grp D antigen and is able to grow under extreme conditions
Enterococcus
E. faecalis, E. faecium, E. durans, E. avium
Most common Enterococcus that causes nosocomial UTI and wound infections
E. faecalis
Identify the Streptococcus Rebecca Lancefield Classification
Causes UTI, wound infections; intraabdominal abscesses, endocarditis, bacteremia
Enterococcus
T/F: Enterococcus are penicillin resistant
T
DOC: cell wall inhibitor (vanco/ampi) + aminoglycoside (genta/strep)
Pathogenic type of Grp D Non-Enterococci
Streptococcus bovis group
No longer a valid species
Group D Non-Enterococci
Non-pathogenic but opportunistic
S. equinus
Group D Non-Enterococci
High association with colon cancer
S. bovis
Streptococcus bovis group include ___ and ___
- S. equinus
- S. gallolyticus
Identify the Streptococcus Rebecca Lancefield Classification
Causes severe pharyngitis; pneumonia, cellulitis, abscess
Grp C Streptococcus
S. equi, S. equsimilis, S. zooepidemicus, S. dysagalactiae
Grp C Streptococcus that causes strangles among horses
S. equi
Identify the Streptococcus Rebecca Lancefield Classification
Miscellaneous lancefield groups
Grp F & G
S. anginosus
Identify the Streptococcus Rebecca Lancefield Classification
Cultures have honeysuckle odor
Group F & G
Identify the Streptococcus Rebecca Lancefield Classification
Normal flora of the GI tract, vaginal tract, and oropharynx
Group G
Viridans Streptococci means “___”
Green
T/F: Viridans Streptococci has no polysaccharide component
T
Most common subacute bacterial endocarditis
Viridans Streptococci
Causes gingivitis & dental caries
Viridans Streptococci
Most common Viridans Streptococci
S. mutans
Viridans Steptococci
Causes dental caries
S. mutans
Viridans Steptococci
Causes endocarditis
S. salivarius
Viridans Steptococci
Causes bacteremia and abscess
S. constellatus
S. pneumoniae is under the ___ group, but is more virulent
S. mitis
Leading cause of community-acquired pneumonia
S. pneumoniae
DOC for S. pneumoniae
Erythromycin & Chloramphenicol
Number 1 cause of bacterial pneumonia
S. pneumoniae
Most important virulent factor of S. pneumoniae that plays a role in the occurence of disease
Polysaccharide capsule
Nutritionally variant Streptococci
- Abiotrophia
- Granulicatella
Nutritionally variant Streptococci requires the growth of which spp. as they produce pyridoxal or thiol needed for growth?
- S. aureus
- K. pneumoniae
- E. coli
These genus resemble Viridans Streptococci and cause diseases similar to those caused by enterococci and streptococci
- Abiotrophia
- Aerococcus
- Gemella
- Lactococcus
- Leuconostoc
- Pediococcus
Identify the strep-like organism
Common airborns organism
Aerococcus
Identify the strep-like organism
Vancomycin-resistant organism that causes endocarditis, wounds, and abscesses
Gemella
Identify the strep-like organism
Vancomycin-resistant organism that is previously part of Group N and causes UTI and endocarditis
Lactococcus
Identify the strep-like organism
Present in plant surfaces, vegetables, and milk products; opportunistic pathogen
Leuconostoc
Identify the strep-like organism
Can grow at 45C and causes bacteremia, asbcess, meningitis among patients who underwent surgery
Pediococcus
Identify the media
Selective for Gr (+) cocci
PEA, CNA
Identify the media
Used for Group B Strep, for vaginal or rectal swab/discharge
Granada Agar
Identify the media
Produces orange coloration in Group B Strep growth
Carrot broth
Identify the media
Selective broth for Group B Strep
Todd Hewitt Broth
Additionaly antibiotics for Todd Hewitt Broth
2 pairs
- Gentamicin & Nalidixic Acid
- Colistin & Nalidixic Acid
Additional requirement of nutritionally variant Strep
Pyridoxal
Antibiotics added to BAP to grow Group A Strep
TMP SXT
GAS are B-hemolytic
Preferred sample for S. pyogenes diagnosis and culture
Throat swab
Identify the Grp of Strep based on BAP growth
Pinpoint, opalescent or gray, smooth and glossy, mucoid; b-hemolytic
Grp A
Identify the Grp of Strep based on BAP growth
Pinpoint, grayish, white mucoid colonies, b-hemolytic (small zone)
Grp B
Identify the Grp of Strep based on BAP growth
Pinpoint colonies; alpha or gamma hemolytic colonies
Grp D Enterococcus
Identify the Grp of Strep based on BAP growth
Tend to dip down in the center and resemble a doughnut as they age
S. pneumoniae
Identify the Grp of Strep based on BAP growth
Minute to small, gray, domed, smooth or matte; alpha-hemolytic or nonhemolytic
Viridans
Identify the Grp of Strep based on BAP growth
Penny coin with raised rim
S. pneumoniae
Identify the Grp of Strep based on BAP growth
a-hemolytic
- S. pneumoniae
- Viridans
Laboratory dx.
Presumptive test for S. pyogenes
- Taxo A
- Sulfamethoxazole
Taxo A (S), Sxt (R)
Laboratory dx.
Presumptive test for Grp B Strep
CAMP Test
(+): Arrow head hemolysis pattern
Christie, Atkins, Munch-Petersen
Laboratory dx.
Used to differentiate b-hemolytic Streptococcus
PYR Test
Laboratory dx.
Used to identify Group D Enterococcus
PYR Test
(+): Red
Laboratory dx.
The only Streptococcus that is PYR Test (+)
S. pyogenes
Laboratory dx.
Used to differentiate S. agalactiae from other B-hemolytic Strep
Hippurate Hyrdolysis w/ Ninhydrin Reagent
(+): GBS, Violet; presence of hippuricase enzyme
Laboratory dx.
Test to differentiate Viridans
Voges Proskauer
S. mitis (-)
Anginosus Grp. (+)
Laboratory dx.
Differentiates Aerococcus and Leuconostoc
LAP Test
Leucine Aminopeptidase Test; (+): Red
Laboratory dx.
Result of Aerococcus and Leuconostoc in LAP test
Negative
Streptococcus, Enterococcus, Pediococcus (+)
Identify the Grp of Strep.
Taxo B (S)
Taxo P (S)
S. pneumoniae
Identify the Grp of Strep.
Taxo A (S)
SMZ (R)
Grp A
Identify the Grp of Strep.
Taxo A (R)
SMZ (R)
Grp B
Laboratory dx.
The production of clear solution in Bile Solubility Test is indicative of the presence of what enzyme?
S. pneumonial autocatalytic enzyme
Laboratory dx.
Susceptibility test for Scarlet Fever
Dick’s test
(+): redness
Laboratory dx.
The Dick’s Test detects what toxin?
Scarlatina toxin
Laboratory dx.
Confirmatory test for Scarlet Fever
Schultz Charlton
(+): Blanching, neutralized phenomenon
Injected w/ antitoxin
Laboratory dx.
Detects antibody against streptolysin coat and increased sequelae risk
ASO Test
Identify the Grp of Strep.
Taxo A (R)
SMZ (S)
Grp C
Sherman’s Classification
10C (-)
37C (+)
42-45C (-)
6.5% NaCl (-)
Skim Milk w/ MB (-)
Pyogenic
Sherman’s Classification
10C (+)
37C (+)
42-45C (+)
6.5% NaCl (+)
Skim Milk w/ MB (+)
Enterococcus
Sherman’s Classification
10C (+)
37C (+)
42-45C (-)
6.5% NaCl (-)
Skim Milk w/ MB (+)
Lactic
Sherman’s Classification
10C (-)
37C (+)
42-45C (+)
6.5% NaCl (-)
Skim Milk w/ MB (-)