Gram positives Flashcards
How is streptococci classified?
haemolysis
What does alpha haemolysis look like?
green
partial
What does beta haemolysis look like?
full
What does gamma haemolysis look like?
white
none
What type of haemolysis does viridens strep have?
alpha haemolysis
What type of haemolysis does group A strep (pyogenes) have?
beta haemolysis
What is haemolysis?
destruction of red blood cells by bacteria
What type of haemolysis does enterococcus have?
gamma haemolytic
What is strep agalactaiae? When is it found?
group B beta haemolytic strep
found in pregnancy and neonates
What is strep gallollyticus sometimes found in?
endocarditis
What is the name of the stain used to distinguish between gram postive and negative?
crystal violet
How does gram postive bacteria respond to crystal violet?
thick peptidoglycan layer traps the crystal violet
How does gram negative bacteria respond to crystal violet?
crystal violet is easily washed away revealing red dye
Where is strep pneumoniae found as a normal commensal?
in and around the mouth
What can strep penumoniae cause?
otitis media/externa, meningitis, penumonia
Can strep pneumoniae be vaccinated against?
YES
How is strep pneumoniae treated?
penicillin
How does penicillin act on strep pneumonia?
binds to enzymes needed to synthesis the peptidoglycan cell wall
What countries have a high level of pneumococcal resistance?
canada china croatia spain Poland pakistan mexico italy USA greece turkey
What is the treatment of strep penumoniae if the patient has been to one of these countries?
IV Vancomycin or Rifampicin
What is the most common type of enterococcus?
E. feacalis
What is the second most common type of enterococcus?
E.faecium
Where is enterococcus normally found as a commensal?
GI tract
What does enterococcus cause?
UTIs
endocarditis
bacteraemia
