Gram positive bacteria Flashcards
What is are 2 common aerobic spore forming bacilli species?
Bacillus cereus (food poisoning) Bacillus anthracis (anthrax)
What kind of bacteria is Corynebacterium diphtheriae? What does it cause?
A Gram positive, aerobic bacilli that does not form spores.
It causes diptheria
Give 4 examples of anaerobic, spore forming bacilli
Clostridium difficle
Clostridium perfringens
Clostridium botulinum
Clostridium tetani
What bacteria causes diarrhoea?
Clostridium difficle
What does clostridium perfringens cause?
Causes gas gangrene, a serious infection has to be treated with penicillin and/or metronidazole.
Is commensal in faeces.
What does clostridium botulinum cause?
Botulism
it is the most potent neurotoxin but is rare in the UK.
What causes tetanus?
Clostridium tetani
What does bacillus cereus cause?
Food poisoning
What form are staphylococci?
Cluster formation
What shape are streptococci?
Chains of spherical bacteria
Give an example of a staphylococci that gives a positive coagulation test result
Staphylococcus aureus
What does staphylococcus aureus cause?
Causes endocarditis (infection of the myocardium) and osteomyelitis (infection of the bone). Is a normal flora in nose and skin.
Give 2 examples of staphylococci that are coagulase test negative
Staphylococcus epidermis Staphylococcus saprophyticus (causes UTI's in women of child bearing age)
What does staphylococcus epidermis cause and where is it found?
It is a skin commensal that is a common cause of catheter, prostheses and ventriculo-peritoneal shunt infections
Give examples of streptococci species that cause partial haemolysis
Streptococcus pneumoniae (pneumococci) Viridians streptococci
What is a haemolysis test and what are the possible results?
Bacteria are grow on a blood agar plate to see what they do to the red blood cells. Haemolysis is the destruction of RBCs.
Partial (alpha)- the blood turns green
Complete (beta)- blood agar turns clear
Non Haemolytic
Give examples of bacteria that causes complete haemolysis in a haemolysis test.
Streptococcus pyogenes
Streptococcus agalactiae
What does streptococcus pyogenes cause and what is it treated with?
sore throats, cellulitis
Acute rheumatic fever, acute glomerulonephritis
Treated with penicillin
What does streptococcus pneumoniae cause and where is it normally found?
Is a upper respiratory tract commensal
Causes pneumonia, can also cause meningitis in children and the elderly.
Vaccine is available.
What does viridians streptococcus cause?
Common cause of endocarditis after dental treatment as it is a mouth commensal.
What is an example of a non-haemolytic streptococci?
Enterococcus faecalis
What is enterococcus faecalis and what does it cause?
It is a gut commensal that causes UTI’s.
There is an increasing problem in hospitals of vancomycin-resistant enterococci.
