Antibiotics Flashcards
What are some of the most common URI pathogens?
- Streptococcus pneumoniae (+)
- Haemophilus influenza (-)
- Moraxella catarrhalis (-)
What are the fluroquinolones?
- regular
- ciprofloxacin
- ofloxacin
- respiratory
- levofloxacin
- moxifloxacin
- gemifloxacin
What are the uses of natural PCNs?
- Syphillis
- Non-purulent skin infections
- usually strep
- Phyaryngitis
- strep throat
What is prophylactic (PPX) therapy?
- ABX therapy used to prevent an infxn that has Ø occurred
What is the spectrum of activity for the 4th gen Cephalosporin?
- Gm +
- MSSA and strep
- Great for Gm- aerobes including:
- P. aeruginosa
- Enterobacter aerogenes and cloacae
What is the spectrum of activity for the cyclic lipopeptide?
- Gm + aerobes
- MRSA
- vanc-resistant Enterococcus faecium
- Enterococcus faecalis
What is ticarcillin and what is the downside to its use?
- antipseudomonal PCN
- short (4hr) DoA and high Na+ content
What are the clinical uses for 1st gen Cephalosporins?
- Not best choice, but could also work on?
- Surgical PPX (not colonic)
- Skin and soft tissue infxns
- Gm+ infxn in PCN-allergic Pts
- Not best choice but can work on:
- URI
- UTI
What is unique about macrolide ABX dosing?
bacteriostatic at lower doses, bactericidal at higher doses
- What are the 3 penicillinase-resistant parenteral PCNs?
- methacillin
- d/c d/t nephrotoxic
- oxacillin
- nafcilin
- most active
- best CNS penetration
- What class is daptomycin?
- What are the clinical uses for daptomycin?
- When should daptomycin absolutely NOT be used?
- Cyclic lipopeptide
- Staph aureus bacteremia and complicated skin/structure infxn
- Ø be used for treatment of pneumonia
- ↑ death rate and serious cardiopulm adverse events vs comparator
What do 3rd gen Cephalosporins have:
- moderate activity for?
- less activity for vs. 1st or 2nd gen
- moderate vs. pseudomonas
- Gm+ cocci
What are fluoroquinolones used for?
- Excellent for:
- Gm- aerobes (H. flu, P. aeruginosa, Enterobacter)
- Shigella and Salmonella
- Atypical organisms
- Mycobacterium
- Less used for:
- staph (good, resistance ↑), moderate strep
- For what conditions do the risks of using fluoroquinolones outweigh the benefits?
- What is the serious side effect included in this FDA warning?
-
conditions:
- acute sinusitis
- acute bronchitis
- uncomplicated UTI
- serious tendonopathies
What are the oral formulations of aminopenicillins?
- issues/benefits?
- dosing?
- ampicillin
- diarrhea, rash
- QID admin
- amoxicillin
- better absorption, less GI effects
- TID
What are aminopenicilins and what makes them unique?
- Extended spectrum PCNs
- good as PCN G for Strep and pneumococci
- Also includes some gram (-)
- “NSHEPS”
- N. meningitidis
- Salmonella
- H. influenzae
- E. coli
- P. mirabilis
- Shigela
- “NSHEPS”
What are the general guidelines for ABX?
- Approved ABX
- Narrowest spectrum
- Proper dose
- Shortest duration
What is empiric therapy?
- ABX therapy used to treat a known/suspected infxn where organism is not specifically known
How is clindamycin used today?
- Acne vulgaris
- toxoplasmosis and plasmodium (protozoa)
What is the microbiologic activity for macrolide ABX?
- Gm +
- Gm - (H. flu)
- genital pathogens
- N. gonorrhoeae, Chlamydia trachomatis, Treponema pallidum
What is the 4th gen Cephalosporin?
Cefepime (cefazolin [1st] + ceftazidime [3rd])
What are some “atypical” URI pathogens and what makes each unique?
- Mycoplasma pneumoniae
- no cell wall
- Chlamydophila pneumoniae
- must infect another cell to reproduce
- Legionella pneumophilia
- unique lipopolysaccharide content in outer cell membrane
What are the 4 major mechanisms of ABX resistance?
- destroy the drug
- enzymatic b/d
- limiting access into cell
- thickened cell wall
- change drug target
- altered binding site
- pump drug out of cell
- efflux pump
What is minimum bactericidial concentration (MBC)?
- [Lowest] of ABX that kills 99.9% of the initial inoculum
What are the common gram negative pathogens?
- Enterobacteriaceae
- PEcK (Klebsiella, E. coli, Proteus)
- Shigella, Salmonella
- SPACE bugs
- Serratia
- Pseudomonas
- Acinetobacter
- Citrobacter
- Enterobacter
What is a minimum inhibitory concentration (MIC)?
- [Lowest] of an ABX that inhibits VISIBLE growth of an organism
- quantitative measure of Rx activity vs a bacteria
What are the 3rd gen Cephalosporins?
- Oral
- cefditoren
- cefdibuten
- cefdinir
- Parenteral
- cefotaxime
- ceftazidime
- ceftriaxone
- What is the spectrum of activity for the 5th gen Cephalosporin?
- What’s it good for?
- Spectrum:
- Gm+ and MRSA
- less Gm- vs 4th gen
- Good for:
- MSSA and MRSA
- Streptococcus
- GNRs
What is fidaxomicin?
Difi cid(e)
- a non-absorbable macrolide-like antibiotic
- so concentrates in the gut
- used exclusively for infxn of C. diff
- What is PCN VK
- Dosing?
- Main Uses?
- An acid stable form of oral natural PCN
- 125-250 mg q6hr
- Strep pharyngitis, PPX for rheumatic heart dz
How are 3rd gen Cephalosporins generally used?
- Gm- meningitis
- CAP and HAP
- bacteremia
- febrile neutropenia
- complicated UTI
- What is Procaine PCN G?
- Uses?
- Dosing?
- IM only PCN G that has detectable levels for 12-24 hours
- used to treat gonorrhea
- doses q8-12 hr