Antimicrobials and Bacterial Resistance Quiz

Microbiology Lecture (L04)

• Treatment and Prevention of Infections is the topic of the lecture.
• A glossary of terms related to antimicrobial agents is provided.
• Bacteriostatic agents slow bacterial growth.
• Bactericidal agents kill bacteria.
• Antimicrobial agents include antibiotics, antivirals, antifungals, and antiparasitics.
• Antimicrobial resistance (AMR) describes when microbes no longer respond to antimicrobial medicines.
• Antibiotics are drugs that treat bacterial infections by killing or stopping bacterial growth.
• Antibiotics have differing spectra of activity; narrow-spectrum antibiotics target specific pathogens, and broad-spectrum antibiotics target a wide variety of pathogens (including both gram-positive and gram-negative bacteria).
• Mechanisms of drug action on bacterial cells:
  • Cell wall synthesis inhibitors (e.g., beta-lactams, vancomycin) disrupt the synthesis of peptidoglycan, a key component of bacterial cell walls.
  • Protein synthesis inhibitors (e.g., aminoglycosides, tetracyclines) interfere with bacterial protein synthesis by targeting ribosomes, resulting in bacterial death or arrest of growth.
  • Nucleic acid synthesis inhibitors (e.g., fluoroquinolones) disrupt DNA replication.
  • Metabolic pathway inhibitors (e.g., sulfonamides) interfere with metabolic pathways essential for bacterial survival.
• Inhibitors of cell membrane integrity, such as polymyxin B and colistin, can disrupt the cell membrane and potentially be toxic to some host cells.
• Inhibitors of nucleic acid synthesis interfere with DNA or RNA synthesis. Fluoroquinolones, metronidazole, and rifampin are examples of drugs targeting nucleic acid synthesis.
• Inhibitors of metabolic pathways often target nucleic acid or amino acid synthesis pathways (e.g., sulfonamides and trimethoprim, which disrupt folic acid synthesis).
• Viral replication: Attachment, penetration, uncoating, biosynthesis, assembly, and release are stages of viral reproduction.
• Antiviral drugs act on various stages of viral replication.
• Antimicrobial resistance:
  • Increased use of antimicrobials and close contact of sick people creates fertile environments for microbes to become drug resistant.
  • Societal pressures, inappropriate use including prescriptive practices, and inadequate diagnosis all contribute to antimicrobial drug resistance.
  • Horizontal gene transfer (plasmids and conjugation) allows microbes to share resistance genes.
• Types of multidrug-resistant organisms (MDROs) are presented

Ideal Antimicrobial Agents

• Ideal antimicrobial agents are microbicidal rather than bacteriostatic.
• They remain potent in bodily fluids.
• They do not lead to resistance.
• They support host defenses.

Additional Topics

• Drug suffixes used in antibiotics, antivirals, and antifungals.
• Prophylaxis (preventative) versus empirical (presumptive) antibiotic treatments.
• Occupational exposures and PEP (post-exposure prophylaxis)
• Vaccine hesitancy
• Vaccines safety (mercury compounds, adjuvants)
• Side effects
• Various diseases and their treatments are mentioned.
• Local immunization program and schedules are presented.
• Decontamination methods, such as cleaning, disinfection, sterilization including the use of ultrasonic cleaners, are discussed.
• Resistance of microorganisms to decontamination
• Different Spaulding classifications of medical devices and their decontamination processes
• Use of biological indicators (Spores test) to verify the efficacy of decontamination processes
• Glossary of terms in immunology including immunity, immunization, vaccines and vaccination, and antibodies and antigens.
• Herd immunity and its importance in disease prevention.