Antimicrobials II Flashcards Preview

Infectious Disease: Unit 2 > Antimicrobials II > Flashcards

Flashcards in Antimicrobials II Deck (20)
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1
Q

Isoniazid: MOA, resistance

A
  • Inhibits InhA in mycolic acid biosynthesis
  • Prodrug- mutations in several genes bactercidal
2
Q

Rifampin: MOA, resistance

A
  • Inhibits transcription by binding to the RNA polymerase
  • Mutations in RNAP bactercidal
3
Q

Ethambutol: MOA, resistance

A
  • Inhibits arabinosyl transferases in cell wall biosynthesis
  • Mutations in EMB genes Static (cidal in MAC?)
4
Q

Pyrazinamide: MOA, resistance

A
  • Depletes energy reserves of cell-membrane effects
  • Prodrug- PCNA gene Better in acidic env. bactercidal
5
Q

Streptomycin: MOA, resistance

A
  • Protein synthesis inhibition 30S ribosomal subunit bactericidal
6
Q

Isoniazid: pharmacokinetics

A
  • Orally available Well distributed Metabolized- I in CRIMES
  • Acetylation rates differ
7
Q

Rifampin: pharm

A
  • Orally available Well distributed – colors fluids orange Metabolized- R in CRIMES
  • Potent inducer of CYP450s
8
Q

Ethambutol: pharm

A
  • Orally available Well distributed; lungs CSF
  • Renal excretion
9
Q

Pyrazinamide: pharm

A
  • Orally available Well distributed; lungs CSF
  • Renal excretion
10
Q

Streptomycin: pharm

A
  • Poor oral abs.(IV/IM)
  • distr. to TBW accum. in kidney, ear
  • Renal excretion
11
Q

Isoniazid: adverse rxns

A
  • Low/Medium
  • Vit B6 deficiency-neuritis
  • Hepatic damage (acetylator status important)
  • EtOH
12
Q

Rifampin:adverse rxns

A
  • Low/Medium
  • Hepatic damage
  • Drug interactions; HIV, steroids, etc….
13
Q

Ethambutol: adverse rxn

A
  • Low/Medium
  • Optic neuritis
  • not for children (< 6) or in pregnancy
  • Gout
14
Q

Pyrazinamide: adverse rxns

A
  • Medium/high
  • Hepatic damage – monitor SGOT levels
  • Gout
  • Not in pregnancy (US)
15
Q

Streptomycin: adverse rxns

A
  • High toxicity
  • Vestibular and auditory toxicity
  • nephrotoxicity
16
Q

Isoniazid: sprectrum/uses

A
  • Mycobacteria only (TB and M.Ka.)
  • Intracellular activity
17
Q

Rifampin: sprectrum/uses

A
  • Mycobacteria and Gram +ve
  • Intracellular activity
  • TB, endocarditis
  • H. flu meningitis prophylaxis
18
Q

Ethambutol: sprectrum/uses

A
  • Mycobacteria only (TB, M.Ka, MAC)
  • Intracellular activity
19
Q

Pyrazinamide: spectrum/uses

A
  • Mycobacteria only
  • Semi-dormant bacteria in caseous lesions (acidic environment)
  • Variable modest intracellular activity
20
Q

Streptomycin: spectrum/uses

A
  • Med. Spectrum Gram – aerobes (E. coli, Pseudomonas)
  • limited +
  • TB – alternative 1st line treatment
  • Not intracellular