Bacteria II Flashcards
What are the functions of Streptolysin O and S? Endotoxin or exotoxin?
Are they produced by Strep Pyogenes, Strep Pneumoniae or both?
Streptolysin O is an exotoxin that is one of the bases of the organism’s beta-haemolytic properties.
Streptolysin S is a cardiotoxic exotoxin and is another beta-haemolytic component.
Only produced by Strep Pyogenes.
Which streptococcal toxin enables streptococcus to penetrate tissues?
Hyaluranidase breaks down hyaluronic acid which is an important component of connective tissue
What is the function of Streptokinase?
Streptokinase activates plasminogen to plasmin, which in turn digests fibrin and other proteins.
What is the function of streptococcal chemokine protease?
Responsible for preventing the migration of neutrophils.
What is Guillian-Barre syndrome?
Guillian-Barre syndrome is a rapid onset of muscle weakness caused by inflammatory response. Usually begins in the peripheries and progress up the limbs.
Which bacteria is the most common cause of Guillian-Barre syndrome?
Campylobacter Jejuni. (an enterococci that causes diarrhoea)
Second most common is CMV.
What is a histological sign of CMV infection?
Owl’s eye lesions seen in cells
A bacteria infection commonly associated with atypical pneumonia and is sometimes associated with cold agglutination
Mycoplasma pneumoniae
Which 2 bacteria are highly associated with toxic shock syndrome?
Staphylococcus Aureus and Group A Streptococcus
What is cold agglutinins and what causes it to form?
Cold agglutinins are usually made by the immune system in response to infections by mycoplasma, HepC, etc. They causes RBC to clump together at low temperatures.
Which bacteria is a common cause of Rheumatic fever?
When does rheumatic fever occurs after this infection?
Group A Streptococcus commonly causes rheumatic fever. Occurs 2-4 weeks later after strep sore throat
Does Mycoplasma have a capsule?
Does Bacillus Anthracis have a capsule?
Does E.Coli have a capsule?
Mycoplasma usually no capsule.
Yes capsule for Bacillus Anthracis and E. Coli
Name the bacteria with the following properties: Purple cocci in chains on gram stain, no bubbles when dipped in hydrogen peroxide, and appears as green cultures on blood agar.
Streptococcus Pneumoniae or Streptococcus Viridans
What is the decolonisation therapy for MRSA?
Correct decolonisation therapy for a newly diagnosed MRSA patient is Mupiricin TDS and Octenisan OD for 5 days, including hair wash with Octenisan twice within the 5 days.
