CSIM 1.44 Antibiotic strategies

Question 1

What are the 5 main target sites for antibiotic action?

Answer 1

• Cell wall
  
  • Biosynthetic pathways (e.g. folate)
  • Protein synthesis
  • Nucleic acids
  • Outer membrane of gram-negatives

Question 2

What are the genuses of:

1) Gram-positive cocci?
2) Gram-negative cocci?
3) Gram-positive rods?
4) Gram-negative rods?

Answer 2

1) Staphylococcus, Streptococcus, Enterococcus, Corynebacterium,
2) Neisseria
3) Diphtheroids, Bacillus, Clostridium
4) E. coli, Haemophilus

Question 3

What antibiotics are usually use for pharyngitis and why?

Answer 3

Often none, as it is usually viral

If bacterial then a penicillin as the causative agent is almost always a gram-positive genus:
• Streptococcus pyogenes
• Corynebacterium diphtheriae

Question 4

What is given in addition to antibiotics in the event of a Corynebacterium diphtheria infection?

Answer 4

An antitoxin

Question 5

What is the treatment of:

1) Community-acquired pneumonia?
2) COPD pneumonia?
3) Hospital-acquired pneumonia?

Answer 5

1) A beta-lactam
2) Co-amoxiclav
3) Piperacillin - tazobactam

Question 6

What is the treatment of:

1) Erysipelas and cellulitis?
2) Necrotising fasciitis

Answer 6

1) Flucloxacillin (+metronidazole if present in an IV drug user)
2) Beta-lactam + antitoxin + metronidazole

Question 7

What is the treatment of:

1) Bacterial meningitis?

Answer 7

up to 3 months of age OR 50+ years:
• Cefotaxime + amoxicillin

3 months - 50 years
• Cefotaxime