L13- Strep and Enterococcus

Is Streptococcus Gram negative or positive?

Positive

Are Streptococcus and Enterococcus catalase negative or positive?

negative

What is a distinguishing characteristics of Streptococcus?

they are found in strings or chains

What does alpha (incomplete) hemolysis look like?

A greenish zone around the colony

What does beta (complete) hemolysis look like?

A clear zone around colony

What does gamma (no) hemolysis look like?

transparent

What does the Lancefield Classification include?

Unique carbohydrate cell wall antigens

What serologic classification do S. pyogenes have?

A

What serologic classification do S. agalactiae have?

B

what does tissue tropism mean?

preference for a particular site of infection

What type of pattern do group A strep. have?

emm pattern

What is the pathogen associated with Group A Strep (GAS)

S. progenies

What pathogen is associated with group B Strep (GBS)

S. agalactiae

What does streptokinase do as a virulence factor?

Lyses blood clots and facilitates the spread of bacteria in tissues

What does DNase do as a virulence factor?

depolymerizes cell-free DNA

Where is Strep usually found?

on skin and mucous membranes in human hosts

What happens during Streptococcal toxic shock syndrome (STSS)

GAS bacteria infect a skin lesion, spread into blood, secrete SPEs which act similar to superantigens

What are the 3 ways in which infection by S. pyogenes can show up?

Pyogenic, Toxigenic, Immune-mediated pathogenesis

What is scarlet fever caused by?

Exotoxins released by S. pyogenes

What happens during invasive GAS disease?

The bacteria eats across flesh and causes life threatening bacterial infection

What is Rheumatic fever?

An autoimmune disease that occurs 2-3 weeks after initiation of pharyngitis

What is rheumatic fever caused by?

cross reactions between antigens of the heart and strep. antigens

What type of transmission do Group B strep have?

Vertical transmission occurring at birth

Group B strep. are the leading cause of _______ and _______ in neonates

Meningitis, and septicemia

What does Streptococcus pneumoniae look like?

They are in pairs and short chains

What does the secretory IgA protease do as a virulence factor?

it disrupts secretory IgA-mediated clearance

What are 3 disease associated with Strep. pneumoniae?

Pneumonia, Meningitis, Bacteremia

What type of Hemolysis does Strep.pneumoniae have?

Alpha hemolytic activity

What type of Hemolysis does Strep. pyogenes have?

beta hemolytic activity

How many serotypes of S.pneumoniae does PPSV23 immunize against?

23

What are pneumococcal antigen conjugated antibiotics?

They are bound to a carrier protein

What does strangles cause in horses?

Swollen lymph nodes, formation of abscesses around nasal passages

What is Strangles caused by?

Strep. equi