Page 132 - MNU-PM502- Pharmaeutical Microbiology Theoritical Book

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

• Efflux: Resistance due to decreased accumulation by bacterial cells.
• Ribosomal protection: through certain reactive protein.

6- Chloramphenicol: There are three mechanisms of resistance to
chloramphenicol:

• Reduced membrane permeability.
• Mutation of the 50S ribosomal subunit

• Production of chloramphenicol acetyltransferase which deactivate the drug.
7- Macrolides
• Structural changes in the target ribosomal RNA.

• Production of drug-inactivating enzymes (esterases or kinases).
• Production of active efflux proteins that transport the drug outside of the

cell.
8- Quinolone: Resistance due to alteration of DNA gyrase.

9- Rifamycins: Resistance due to mutation coding RNA polymerase

10- Sulfonamides and trimethoprim: Resistance due to

• Plasmid codes for enzyme that has lower affinity to drug

Impact of Antibiotic resistance

1. Increase morbidity

2. Increased length of hospital stay

3. Increased healthcare costs

4. Increased mortality

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