Page 167 - MNU-PM502- Pharmaeutical Microbiology Theoritical Book

Pharm D- Clinical Pharmacy Program Third Level Pharmaceutical Microbiology& Antimicrobials (PM 502)

◼ Interpretation of results

- By comparing with the diameters
with “standard tables”

- Susceptible
- Intermediate

susceptible
- Resistant

Advantages

• Simplicity

• Low cost

• The ability to test enormous numbers of microorganisms and antimicrobial
agents

• The ease to interpret results.

Disadvantages

• Not appropriate to determine the minimum inhibitory concentration (MIC),

as it is impossible to quantify the amount of the antimicrobial agent diffused
into the agar medium.

• Cannot distinguish bactericidal and bacteriostatic effects.

Antibiotic multi-susceptibility test ring (AMT ring)

• Another form of a disc diffusion assay uses many antibiotics simultaneously.

The ring comprises many discs, each of which is treated with a different test
compound

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