Streptococcus spp. and Enterococcus spp.

Review well!! < 3 (Review also the workflow diagram:) )

* Catalase (-)
* Gram (+) cocci in pairs and in chains
* more elongated
* **can ferment glucose** but no gas

*Streptococcus spp.*

**What type of hemolytic pattern is this and** __**part of Streptococci**__**?**

* complete lysis of rbcs around colony
* clear area around colony

β-hemolytic pattern

**What type of hemolytic pattern is this and** __**part of Streptococci**__**?**

* partial lysis of rbcs around colony
* greenish discoloration of area around colony

α-hemolytic pattern

**What type of hemolytic pattern is this and** __**part of Streptococci**__**?**

* no lysis of rbcs around colony
* no change in agar

y-hemolytic patter/ nonhemolytic

**What type of hemolytic pattern is this and** __**NOT part of Streptococci**__**?**

* small area of intact rbcs around colony surrounded by a wider zone of complete hemolysis

(alpha prime) α’ hemolytic pattern

Who proposed Lancefield Classification?

Rebecca Lancefield (1930)

It is part of **β group**: Acid labile

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* Specie for GROUP A?

*S. pyogenes*

It is part of **β group**: Acid stable

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* Specie for GROUP B?

*S. agalactiae*

It is part of **β group**: Acid labileIt

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* Species for GROUP C?

*S. dysagalactiae* & *S. equi*

It is part of **α group**:

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* don’t have lancefield, under viridans pneumoniae (S. mitis group) because they don’t have C carbohydrate

*S. pneumoniae*

It is part of **α group**:

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* Species for Viridans Streptococci?

* *S. bo*vis group
* *S. anginosus* group
* *S. mutants* group
* *S. mitis* group
* *S. salivarus* group

It is part of **non-hemolytic pattern**: Acid labile

Group D streptococci

*Enterococcus spp.*

Group A streptococcus (GAS) %%**Streptococcus pyogenes**%%

Virulence factor:

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* __resist phagocytosis__ & adherence to mucosal cells
* **>150 serotypes** (M1, M2…..) M1 is common

M protein

Group A streptococcus (GAS) %%**Streptococcus pyogenes**%%

Virulence factor:

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* __**adherence to epithelial cells**__

Protein F (fibronectin-binding protein) & Lipoteichoic acid

Group A streptococcus (GAS) %%**Streptococcus pyogenes**%%

Virulence factor:

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* __impede phagocytosis__
* **most noticeable in very young cultures** (18-24 hrs culture)

Hyaluronic acid capsule

Group A streptococcus (GAS) %%**Streptococcus pyogenes**%%

Virulence factor:

Streptolysin O (SLO) and Streptolysin S

What Immunogenicity is this?

* can initiate an immune respond
* can trigger immune system
* Antigen that initiate to produce
* Antibody (Anti-streptolysin O)

Highly immunogenic

What Immunogenicity is this?

* cannot initiate immune system

Non-immunogenic

Group A streptococcus (GAS) %%**Streptococcus pyogenes**%%

Virulence factor:

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* __spread of streptococc__i in tissue by liquefying pus
* **potent protease** (__interfere with phagocytosis__)
* **immunogenic**
* A, B, C, and D (**B- common**)

Deoxyribonuclease (DNase)

Group A streptococcus (GAS) %%**Streptococcus pyogenes**%%

Virulence factor:

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* **allows** the __bacteria to escape from blood clots__
* **lysis of fibrin clots** through the action of on plasminogen → plasmin → lyses clot
* **immunogenic** but __not specific to GAS__

Streptokinase/ fibrinolysin

Group A streptococcus (GAS) %%**Streptococcus pyogenes**%%

Virulence factor:

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* **spreading factor**
* **enzyme** that __solubilizes the ground substance of mammalian connective tissues__
* Hyaluronic acid

Hyaluronidase

Group A streptococcus (GAS) %%**Streptococcus pyogenes**%%

Virulence factor:

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* cause a red spreading rash (scarlet fever), referred to as __**Erithrogenic toxin**__
* SpeA, SpeB, SpeC, and SpeF

Streptococcal Pyrogenic Exotoxins

Group A streptococcus (GAS) %%**Streptococcus pyogenes**%%

Infections:

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* known as “__**Strep throat**__”
* most common clinical manifestations of GAS infection
* pharyngitis and tonsillitis

Bacterial pharyngitis

Group A streptococcus (GAS) %%**Streptococcus pyogenes**%%

Infections:

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* **impetigo**, cellulitis, erysipelas, wound infection, arthritis or scarlet fever

Pyodermal infections

Group A streptococcus (GAS) %%**Streptococcus pyogenes**%%

Infections:

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* **invasive infection** characterized by __rapidly progressing inflammation__ and __necrosis__ of the skin

Necrotizing Fascitis (NF)

%%Necrotizing Fascitis (NF)%%

Species:

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1. TYPE 1 NF?
2. TYPE 2 NF?
3. TYPE 3 NF?

1. *Vibrio* spp.
2. “flesh-eating bacteria”- *Streptococci* spp.
3. *Clostridium* spp.

If the portal of entry is the skin. Lesion race is red. There is massive browny edema and rapidly advances to demarcated margin of infection.

Erysipelas

* Acute rapidly spreading infection of the skin as well as subcutaneous tissue.
* After mild trauma, burn wound, or surgical incision
* Lesion is not race, its flat, can’t look margin of infection

Cellulitis

Group A streptococcus (GAS) %%**Streptococcus pyogenes**%%

Infections:

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* SpeA
* M1 and M3

Streptococcal Toxic Shock Syndrome

Group A streptococcus (GAS) %%**Streptococcus pyogenes**%%

Infections:

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* **RHEUMATIC FEVER** and **ACUTE GLUMERULONEPHRITIS** (1-3 weeks)
* Class 1 M protein (RF); Class 1 & 2 M protein (AGN)
* **TOC**: Penicillin

Poststreptococcal sequelae

Group B streptococcus (GBS) %%**Streptococcus agalactiae**%%

Virulence factor:

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* **resist phagocytosis** but is __ineffective after opsonization__
* Component: __**sialic acid**__

Capsule

Group B streptococcus (GBS) %%**Streptococcus agalactiae**%%

Virulence factor:

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* products not involve in virulence

Hemolysin, CAMP factor, neuraminidase, Dnase, hyaluronidase & protease

Group B streptococcus (GBS) %%**Streptococcus agalactiae**%%

Infection:

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* vertical transmission
* colonization in vagina and rectal area

Invasive disease of newborn

What specie is this?

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* small, transparent, and smooth with a well-defined area of β-hemolysis

*S. pyogenes*

What specie is this?

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* grayish white mucoid colonies surrounded by a small zone of β-hemolysis

*S. agalactiae*

Biochemical Test:

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__**Principle**__: catalase mediates the breakdown of hydrogen peroxide (30% H202) into oxygen and water

Catalase

Biochemical Test: CATALASE

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Result:


1. (+) bubble formation (?)
2. (-) no bubble formation (?)

1. Staphylococci & Micrococci
2. Streptococci & Enterococci

Biochemical Test (%%**S. pyogenes**%%)

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Principle: determine the effect of a small amount of bacitracin (**0.04U**) on an organism

Bacitracin Test

Biochemical Test (%%**S. pyogenes**%%): BACITRACIN TEST

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Result:


1. (+) sensitive- presence of zone of inhibition around the disk (?)
2. (-) resistant- no zone of inhibition (?)

1. S. pyogenes
2. other β-hemolytic streptococcus (Group B & C)

Biochemical Test (%%**S. pyogenes**%%)

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__**Principle**__: differentiate S. pyogenes from other β-hemolytic streptococcus by the presence of the enzyme L-pyrroglutamylaminopeptidase

Pyrrolidonyl Arylamidase (PYR) Test

Biochemical Test (%%**S. pyogenes**%%): PYRROLIDONYL ARYLAMIDASE (PYR) TEST

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Result:


1. (+) bright red color (?)
2. (-) no color change or an orange color (?)

1. S. pyogenes
2. Other β-hemolytic streptococcus (Group B & C)

Biochemical Test (%%**S. agalactiae**%%)

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__**Principle**__: determine the capability of organism to hydrolyze hippurate

__**Reagent:**__ ninhydrin

Hippurate Hydrolysis Test

Biochemical Test (%%**S. agalactiae**%%): HIPPURATE HYDROLYSIS TEST

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Result:


1. (+) deep purple color (?)
2. (-) colorless or slightly yellow pink color or light purple (?)

1. S. agalactiae
2. Other β-hemolytic streptococcus (S. pyogenes)

Biochemical Test (%%**S. agalactiae**%%)

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__**Principle:**__ detection of diffusible extracellular protein (CAMP factor) that acts synergistically with the beta-hemolysin of S. areus to cause enhanced lysis of red blood cells

CAMP test

Biochemical Test (%%**S. agalactiae**%%): CAMP TEST

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Result:


1. (+) **enhanced hemolysis** indicated by an arrowhead-shaped zone of beta-hemolysis at the juncture of the two organisms (?)
2. (-) **no enhancement** of hemolysis (?)

1. S. agalactiae
2. Other β-hemolytic streptococcus

It is part of alpha-hemolytic and member of the *S. mitis* group

__**Cell wall:**__ C substance

* reacts with CRP to form precipitate

Streptococcus pneumoniae

%%**Streptococcus pneumoniae**%%

Virulence factor:

* used to classify *S. pneumoniae* into more than 90 serotypes
* __**strains that lack capsule**__: non-pathogenic/avirulent

Capsular polysaccharide

* normal microbiota of the upper respiratory tract, the female genital tract, and the gastrointestinal tract
* viridans means “green”

Viridans streptococcus (Group of bacteria)

%%**Viridans streptococcus**%%

Infection:

* most common cause of _________________
* oral infections such as gingivitis and dental caries

Subacute bacterial endocarditis

%%**Viridans streptococcus**%%

Virulence factor:

* polysaccharide capsule and cytolysin
* adherence and colonization in endocarditis

*S. anginosus* group

%%**Viridans streptococcus**%%

Virulence factor:

* M proteins, SLO, hyaluronidase, and DNase

Groups C and G streptococci

%%**Viridans streptococcus**%%

Virulence factor:

* express the D antigen

Group D streptococci and *S. bovis* group

**Direct Microscopic Examination**

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* Effusions: Gram (+) pneumococci with numerous WBC
* CSF: Gram (+) cocci in pairs with numerous WBC
* Gram (+) cocci in pairs or in singly or in short chains (diplococci)
* ends of the cells are slightly pointed, giving them an oval or lancet shape

*S. pneumoniae*

**Direct Microscopic Examination**

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* Gram (+) cocci in chains and in pairs

Viridans streptococcus

**Macroscopic examination**

**Colonies:**

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* round, glistening, wet, mucoid, dome-shaped/doughnut appearance with large zone of α-hemolysis on BAP surrounding the colonies

*S. pneumoniae*

**Macroscopic examination**

**Colonies:**

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* minute to small, gray, domed, smooth or matte; alpha-hemolytic or nonhemolytic

Viridans streptococcus

**Biochemical Test:**

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__**Principle**__: determine the effect of optochin on an organism

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* __**Chemical name**__: ethylhydrocupreine hydrochloride

Optochin Test

**Biochemical Test: OPTOCHIN TEST**

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Result:


1. (+) Zone of inhibition is 14 mm or greater in diameter, with 6-mm disk (?)
2. (-) No zone of inhibition (?)

1. S. pneumoniae
2. other α-hemolytic streptococcus, streptococcus viridans

**Biochemical Test:**

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__**Principle**__: bile or a solution of a bile salt rapidly lyses pneumococcal

* bile salts lowers the surface tension between the bacterial cell membrane and the medium
* also known as **“sodium desoxycholate” or “sodium deoxycholate”**

Bile Solubility Test

Biochemical Test: BILE SOLUBILITY TEST

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Result: Plated


1. (+) Lysed colonies (?)
2. (-) Intact colonies (?)

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Result: Tubed (broth)


1. (+) clear broth (?)
2. (-) turbid broth (?)

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Plated & Tubed (broth)


1. *S. pneumoniae*
2. Other α-hemolytic pattern

**Antigenic Tests:**

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__**Principle**__: pneumococcu mixed with specific anti-polysaccharide serum on a slide, the capsule swells markedly, and the organisms agglutinate by cross-linking

* useful for rapid identification and for typing of the organisms, either in sputum or in cultures

Quellung Reaction (in slide)

Antigenic Tests:

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Result:


1. (+) swelling of the capsule (?)
2. (-) no swelling of the capsule (?)

1. S. pneumoniae
2. Other α-hemolytic streptococcus

**Biochemical Test:**

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__**Principle:**__ detection of the enzyme leucine aminopeptidase

Substrate: **Leucine-β-naphthylamide → β-naphthylamine + cinnamaldehyde reagent**

LAP Test

**Biochemical Test:**

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Result:


1. (+) Red color (?)
2. (-) No color change or an slight yellow color (?)

1. Viridans Streptococci
2. Other α-hemolytic streptococcus

* __previously classified as group D streptococci__
* has D antigen
* normal flora of intestinal tract of human and animals
* nonhemolytic, α-hemolytic or β-hemolytic
* **pseudocatalase reaction**
* PYR (+)

Enterococcus spp.

%%**Enterococcus faecalis**%%

Virulence Factor:

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* colonization of the species and adherence to heart valves and renal epithelial cells

Extracellular surface adhesin proteins, extracellular serine protease, and gelatinase

%%***Enterococcus faecalis***%%

Virulence Factor:

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* similar to bacteriocins produced by gram-positive bacteria

Cytolysin

**What specie is belong to this Infections?**

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* nosocomial infections (UTI & bacteremia)
* endocarditis in elderly patients
* intraabdominal or pelvic wound infections

*Enterococcus faecalis*

%%**Streptococcus-like bacteria**%%

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* previously known as __**nutritionally variant streptococci**__
* require sulfhydryl compounds for growth
* oral and gastrointestinal microbiota
* satellitism on BAP with S. aureus
* **10 mg/L pyridoxal hydrochloride**
* **fastidious**

*Abiotrophia* and *Granulicatella* spp.

%%**Streptococcus-like bacteria:**%% ***What specie is this?***

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Biochemical Test:

\-production of

* α-galactosidase
* β-galactosidase
* β-glucuronidase

\-hippurate hydrolysis

\-arginine hydrolysis

\-acid production from trehalose & starch

*Abiotrophia* and *Granulicatella* spp.

%%**Streptococcus-like bacteria**%%

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* __**common airborne organism**__
* o**pportunistic pathoge**n associated with __bacteremia, endocarditis, and UTI in ICP__
* __**weak catalase or pseudocatalase**__
* Growth in 6.5% NaCl
* *A. viri*dans: bile esculin & PYR (+)
* *A. urin*ae: bile esculin & PYR (-)

*Aerococcus* spp.

%%**Streptococcus-like bacteria**%%

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* __**similar to viridans streptococci in colonial morphology**__
* α-hemolysis or nonhemolytic
* **gram (-) cocci in pairs, tetrads, clusters, or short chains**
* endocarditis, wounds, and abscesses
* *G. haemolysans*

*Gemella* spp.

%%**Streptococcus-like bacteria**%%

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* __previously classified as group N streptococci__
* **gram (-) cocci in singly, in pairs or in chain**
* __**physiologically similar to enterococci**__
* α-hemolysis or are nonhemolytic
* UTI & endocarditis

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**Biochemical Tests**

* differentiate from enterococci (acid production from CHO)

*Lactococcus* spp.

%%**Streptococcus-like bacteria**%%

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* __**catalase (-), gram (+) cocci with irregular morphology**__
* intrinsically resistant to vancomycin
* found on plant surfaces and vegetables, and in milk products
* **meningitis, bacteremia, UTIs, and pulmonary infections**

*Leuconostoc* spp.

%%**Streptococcus-like bacteria**%%

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* __**facultative anaerobe, gram (+) cocci in pairs, tetrads, and clusters**__
* grow at 45 C
* intrinsically resistant to vancomycin
* **gastrointestinal abnormalities or undergone abdominal surgery**

*Pediococcus* spp.

%%**Streptococcus-like bacteria**%%

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* α-hemolytic
* **PYR (+)**
* **LAP (-)**
* vancomycin susceptible

*Globicatella sangius*

%%**Streptococcus-like bacteria**%%

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* __**otitis media in children**__
* non-hemolytic or α-hemolytic
* **PYR (+)**
* **LAP (+)**
* Grow slowly in 6.5% NaCl

*Alloiococcus otitidis*

%%**Streptococcus-like bacteria**%%

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* wound infections
* **misidentified as** ***A. viridans***

*Helcococcus kunzii*

C.A.M.P

Christie, Atkins, Munch-Petersen