What is FQ's MoA? - Bacteriocidal or bacteriostatic?
Inhibition of DNA gyrase and topoisomerase IV - Bacteriocidal
What is FQ's primary mechanism of resistance? - What are some additional MoR's it has?
Chromosomal mutations in DNA gyrase or topoisomerase IV - Also development of efflux pumps, plasmid-mediated resistance, altered cell wall permeability (porins)
Which of the FQ's are active against gram-positive aerobes? (Which aren't, then?)
Levofloxacin, moxifloxacin, gemifloxacin (Not ciprofloxacin!)
Describe the relative activity of FQs against gram-negative aerobes. What about for pseudomonas?
cipro = levo > moxi cipro > levo, NOT moxi or gemi
Which of the FQ's are active against anaerobes?
Which of the FQ's are active against atypical bacteria?
Which FQ(s) are useful against CA-PNA (CAP)?
Levo, moxi, gemi
Which FQ(s) are useful against HA-PNA?
Cipro (+ something for gram-positive coverage), levo
Which FQ(s) are useful against sinusitis/bronchitis?
Which FQ(s) are useful against UTI/prostatitis?
Besides previously mentioned, what else are FQs useful for? (not sure how to ask this question)
Bone infections, STD’s, TB, intra-abdominal w/ added anaerobe coverage
What are the most common adverse affects of FQs? (2) What else can occur?
GI, CNS - Prolonged QTc interval - Tendonitis, tendon rupture - Hepatotoxicity, photosensitivity, hypersensitivity, rash, articular damage
What demo should not use FQs? (contraindicated)
Pregnant women and children
What drugs do FQs interact w/?
- Divalent, trivalent cations: separate administration to avoid chelation and decreased absorption - Warfarin, cyclosporine, theophylline
Methicillin-susceptible Staphylococcus aureus, Streptococcus pneumoniae (including PRSP), Viridans streptococci, and Enterococcus spp. are eg's of what class of bacteria?
Enterobacteriaceae including Citrobacter spp. E. coli, Klebsiella spp, Enterobacter spp, Proteus spp, Salmonella, Shigella, Serratia marcescens, etc; H. influenzae, M. catarrhalis, Neisseria spp., and Pseudomonas aeruginosa are eg's of what class of bacteria?
Bacteroides spp such as b. fragilis are eg's of what class of bacteria?
Legionella pneumophila, Chlamydophila and Chlamydia spp., Mycoplasma spp. and Ureaplasma urealyticum are eg's of what class of bacteria?
All of the FQs are eliminated mostly through the __________ with the exception of __________, which is eliminated through the __________.
- kidney - moxi - liver (therefore can't treat UTI)
Metronidazole is mainly used against what class of microbe?
What is the MoA of metronidazole? - What molecule is responsible for this and how? - Bacteriocidal or bacteriostatic?
Inhibits DNA synthesis - Ferredoxins (which nlly make ATP). Metronidazole binds them and creates an e- sink. Drives more drug into cell and reactive species are made. - Bacteriocidal
How common is the development of resistance w/metronidazole? What are 2 ways in which bugs acquire resistance to metronidazole?
*Uncommon - Altered growth requirements (e.g. higher local O2 conc.) - Altered ferredoxin levels (lower levels)
What 2 types of anaerobic bacteria is metronidazole most active against?
- Bacteroides spp. (all) - Clostridium spp. (all)
Metronidazole: - IV/PO or both? - Does it penetrate the CSF? - How is it eliminated?
- Both - Yes - Liver
What are the clinical uses of metronidazole? Metronidazole is the drug of choice for _____________.
- Anaerobic Infections (including in the CNS): Intraabdominal, pelvic, (skin/soft tissue), diabetic foot and decubitus ulcer infections; brain abscess, trichomonas MILD to MODERATE c-dif dz
What are the most common side effects from metronidazole? What are the most serious side effects?
- GI (stomatitis--metallic taste) - CNS (peripheral neuropathy) - Teratogenic (avoid during pregnancy)
What 2 important drugs does metronidazole interact with?
- Warfarin (increased anticoagulant effect) - Alcohol (disulfiram rxn; don't give to alcoholics)
FQs are the DOC for what atypical bacterium?
What is the target organism for cipro and levo when targeting gram-negative aerobes?
Pseudomonas aeruginosa (NOT moxi)
What are the target organisms for levo, moxi, and gemi when targeting gram-positive aerobes?
- Methicillin-susceptible Staphylococcus aureus* - Streptococcus pneumoniae (including PRSP)*
Which FQ has good CSF penetration?
Trichomonas vaginalis Entamoeba histolytica Giardia lamblia Gardnerella vaginalis are all examples of what class that metronidazole inhibits?
Bacteroides spp. (ALL)* Fusobacterium Prevotella spp. Clostridium spp. (ALL)* Helicobacter pylori Are all examples of what class of organism that metronidazole inhibits?