What test differentiates between gram positive cocci?
Catalase test
What is catalase positive?
Staphylococcus
What is catalase negative?
Streptococcus
How are staphylococcus arranged?
Clusters
How are streptococcus arranged?
Chains
What is the coagulase test?
An enzyme produced by staph aureus coverts soluble fibrinogen into insoluble fibrin
What is positive for the coagulase test?
S.aureus
What is negative for the coagulase test?
Staph epidermidis and saprophyticus
What is alpha haemolytic strep?
Greening on blood agar
What is beta haemolytic strep?
Clear on blood agar
What is gamma haemolytic strep?
No lysis on blood agar
Name beta haemolytic strep?
S.pyogenes
What test differentiates between alpha haemolytic strep?
Optochin test
Sensitive to optochin disc?
S.pneumonia
Resistant to optochin disc?
Viridans strep
Gamma haem strep?
Enterococcus
Gram positive rods?
Corneybacteria, mycobacteria, listeria, bacillus, nocardia
Which gram negative bacilli appear pink on maccconkey?
E.coli and klebsiella
What type of bacteria are pink on MacConkey?
Lactose fermenting
What type of bacteria are white on MacConkey?
Non-lactose fermenting
Non lactose fermenting bacteria?
Shigella, salmonella, pseudomonas, proteus
Which test differentiates between the non-lactose fermenting bacteria?
Oxidase test
What is oxidase positive?
Pseudomonas
What is oxidase negative?
Shigella, salmonella and proteus
Gram negative cocci?
Neisseria, moraxella
Antibiotics to treat shigella?
Quinolones, Azithromycin
Antibiotics to treat salmonella?
Amoxicillin, quinolones, macrolides
Antibiotics to treat neisseria?
Cephalosporins
Antibiotics to treat MRSA?
Gentamicin, Vancomycin
Treatment for bacterial meningitis?
Cephalosporins: IV cefotaxime/ IV ceftriaxone
What type of antibiotics should you use for gram positive and why?
Usually use penicillins as they have thick walls and they inhibit cell wall synthesis/
What antibiotic would you give to someone with a penicillin allergy?
A macrolide
Give 2 examples of a macrolide?
Clarithromycin and erythromycin
Which antibiotic should you not give to pregnant women?
Trimethoprim as it inhibits folic acid synthesis
What should you treat UTI’s with?
Nitrofurantoin and trimethoprim
What stain is used for Mycoplasm tuberculosis?
Ziehl-Neelsen stain (stains red)