Choosing Antibiotic (F1)

Question 1

LO’s

Answer 1

Describe the basis on which antibiotic choice is made in clinical practice Describe why different types of bacteria are treated more effectively by different classes of antibiotics

Question 2

Why do we have to give the right antibiotic?

Answer 2

1. Resistance
2. So it works
3. Cost

Question 3

How do we choose the right antibiotic?

Answer 3

1. Take sample: blood, urea, skin, faeces
2. Decide on the right culture: eg blood
3. Identify the organism: microscopy for the bacteria’s morphological features, but nowadays use PCR machine to check the DNA.
4. Check which bacteria is susceptible to which antibiotic:
   
   1. Inoculte (known amount of bacteria in solution) and place it in different antibiotic dilutions. This is to find the minimum inhibitory concentration (the minimum concentration of antibiotic that is effective against the bacteria). We use a 96 plate for this. ABCD concentration of antibiotic halves at each letter. Clear = bacteria can’t grow.
   2. Or can use the antibiotic gradient method.
   3. Or can use disk diffusion test.