Antimicrobial Chemotherapy Booklet Flashcards
What is the Minimal Inhibitory Concentration?
The minimum concentration of antimicrobial needed to inhibit visible growth of a given organism
What is the Minimal bactericidal concentration?
The minimum concentration of the antimicrobial needed to kill a given organism
What are the main sites of antibiotic action?
- Inhibition of nucleic acid synthesis
- Inhibition of protein synthesis
- Inhibition of cell wall synthesis
What antibiotics Inhibit of cell wall synthesis?
Beta lactams
Glycopeptides
What is the action of penacillins and cephalosporins?
Inhibit cell wall synthesis
What antibiotics make up the beta lactams?
penacillins and cephalosporins
What enzymes are involved with the action of penicillin and cephalosporin?
Penicillin-binding proteins
What antibiotics make up the glycopeptides?
Vancomycin
Teicoplanin
Glycopeptides are effective against what?
Gram positive organisms
Vancomycin and Teicoplanin are used against what?
Gram positive organisms
What risk is associated with Vancomycin?
Toxicity
Which antibiotics inhibit protein synthesis?
- Aminoglycosides
- Macrolides and Tetracyclines
- Oxazolidinones (Linezolid)
- Cyclic Lipopeptide (Daptomycin)
Gentamicin is what type of antibiotic?
Aminoglycoside
How does gentamicin affect bacteria?
Inhibition of protein synthesis
Aminoglycosides/Gentamicin are typically used in the treatment of what?
Serious Gram negative infection
Macrolides and Tetracyclines are used in what?
Gram +ve infections in penicillin allergic patients
Daptomycin works how? When is it indicated?
Daptomicin Inhibits protein synthesis
Gram +ves especially MRSA
How do Trimethoprim and sulphamethoxazole work?
Inhibit Nucleic acid synthesis
What are the indications and contraindications of ciprofloxacin?
Gram -ve organisms
not used in children
What are the common mechanisms of bacterial resistance?
Intrinsic resistance
Acquired resistance
What are the mechanisms of acquired bacterial resistance?
Spontaneous mutation
Species - species spread via plasmids or transposons
What are the mechanisms of Resistance to b–lactam antibiotics?
Production of beta-lactamase
Alteration of penicillin binding protein target site
Which beta-lactam antibiotics can be used in beta-lactamase producing bacteria i.e. Staph aureus?
Co-amoxiclav (beta-lactamase inhibitor clavulanic acid)
Flucloxacillin
MRSA is resistant to what?
All penicillins and cephalosporins
What is the impact of Extended spectum beta-lactamases?
Produced by some gram -ve bacteria
Renders them immune to all Beta-lactam agents
What agents fall under ‘Beta-lactams’?
Penicillins and Cephalosporins
Outline the main classes of antibiotics
B-lactams (Cephalosporins and Penicillins)
Aminoglycosides
Glycopeptides
Macrolides
Quinolones
Name 3 penicillins and their uses
Benzyl penicillin - IV use in
Amoxicillin - streptococci
Co-amoxiclav - β-lactamase producing coliforms
Flucloxacillin - Staph
Piperacillin - Pseudomonas
Carbapenems - Broad spec
Name a cephalosporin and its use
Ceftriaxone
Ceftazidime
Increase risk of Clostridium difficile
Name 2 Glycopeptides and their uses?
Parenteral use only
Vancomycin - (Monitor as toxic)
Teicoplanin
Use in gram positives
Name 2 Macrolides and their uses?
Clarithromycin/Erythromycin - alternative to penicillin in gram positives
Azythromycin - Chlamydia
Name 2 Quinolones and their uses?
Wide action against gram negative bacteria
Pseudomonas
Ciprofloxacin
Levofloxacin
What is the indication for metronidazole?
Gram -ve and +ve anaerobes
What is the indication for fusidic acid?
Used with flucloxacillin against Staphylococcus aureus
What is the indication for Trimethoprim?
Urinary Tract infections
What are the main drugs which confer a risk of Clostridium difficile infection?
Clindamycin
Cephalosporins
Co-amoxiclav
Ciprofloxacin
Outline the use of Tetracyclines?
Broad spectrum
Teratogenic
Outline the use of Clindamycin?
Very good tissue penetration vs gram +ves
Risk C. diff
Outline the use of Linezolid?
Use vs MRSA
Bone marrow suppression
Outline the use of Daptomycin?
MRSA
What antibiotics are used in treatment of C. difficile infection?
Vancomycin
Metronidazole
What antibiotics are indicated in use for Urinary tract infections?
Nalidixic acid
Nitrofurantoin
Trimethoprim
Give 5 side effects of antibiotic use?
Allergy - Immediate -or- delayed
GI
Thrush
Liver toxicity
Renal toxicity
Neurotoxicity
Haemotoxicity
Hepatotoxicity is associated with which antimicrobials?
Tetracycline
Flucloxacillin
Isoniazid and Rifampicin
Renal toxicity is associated with which antimicrobials?
PMH renal disease
Aminoglycosides (Gentamicin)
Vancomycin
Neuro toxicity is associated with which antimicrobials?
Hearing - Aminoglycosides, vancomycin
Vision - Ethambutol
Encephalopathy
Peripheral neuropathy
When should combination antimicrobial therapy be considered?
Mixed infection
Synergistic effects
Avoiding resistant strains - TV, HIV
Which antibiotics should have levels monitored for toxicity?
Vancomycin
Gentamicin
What are the functions of the laboratory in antimicrobial use?
Advice
Efficacy and toxicity
Susceptibility test (Automated, E test)
What are the main classes of Anti-fungal drugs?
Polyenes
Azoles
Allylamines
Echinocandins
Outline the use of Polyenes
Amphotericin B - serious fungal infections, toxic
Nystatin - topical fungal infections
Outline the use of Azoles
Fluclonazole - yeast infections
Itraconazole and Voriconazole - aspergillosis
Outline the use of Allylamines
Terbafine - skin/nail fungal infections
Outline the use of Echinocandins
Serious Candida and Aspergillus infections
What drgug is indicated in HSV and Varicella zoster virus?
Aciclovir
Outline the use of Anti-herpes drugs?
Aciclovir, Famciclovir - HSV, Varicella
Ganciclovir - infections in the immunocompromised
Valganciclovir - CMV
Foscarnet
Outline the use of Anti-HIV drugs?
AZT (nucleoside analogue)
2 nucleoside analogue reverse transcriptase inhibitors
plus either:
- non-nucleoside reverse transcriptase inhibitor
- Protease inhibitor
Outline the use of Hep B/C drugs?
Interferon-a(lpha) - serious side effects
Lamivudine
