Term
|
Definition
| most commonly prescribed aminoglycoside |
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Term
|
Definition
| an anti-pseudomonal aminoglycoside |
|
|
Term
| What is a common first line antibioitic for uncomplicated UTI's? |
|
Definition
|
|
Term
| Which drugs require therapeutic drug monitoring? |
|
Definition
| drugs with low therapeutic range; aminoglycosides and vancoymycin |
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Term
| Combination therapy may prevent the emergence of resistance of what? |
|
Definition
- mycobacterium tuberculosis
- s aureus (fluroquinolone/rifampin)
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|
|
Term
| What are transglycosylases? |
|
Definition
| they are a PBP that is takes nascent peptidoglycan to backbone of cell wall |
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|
Term
| What are carboxypeptidases and transpeptidases? |
|
Definition
- PBPs with a similar function
- cleave terminal D-ala from pentapeptide
- ratio determines extent of cross linking
- thought to influence cell shape
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|
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Term
| Beta lactams are contraindicated in what type of patient? |
|
Definition
| patient with immediate hypersensitivity reaction history! |
|
|
Term
| if there is a history of skin rash with penicillins, what should you use? |
|
Definition
| cephalosporins are almost always safe! |
|
|
Term
| What are types of glycopeptides? What do they act against? |
|
Definition
They are cell wall active agents;
vancomycin/teicoplanin
act against gram positive!! |
|
|
Term
| What is the action of glycopeptides? |
|
Definition
| bind to terminal D-ala of nascent cell wall peptides and prevent cross-linking of these peptides to create mature peptidoglycan |
|
|
Term
| What are the 2 types of cell wall active agents? |
|
Definition
- beta-lactams
- glycopeptides
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|
|
Term
| S. pneumoniae is responsible for what type of B-lactam resistance? |
|
Definition
|
|
Term
| MRSA is responsible for what type of beta-lactam resistance? |
|
Definition
|
|
Term
| What are the 4 types of B-lactam resistance? |
|
Definition
- B-lactamase (msot common)
- altered PBPs
- Novel PBPs
- altered permeability
|
|
|
Term
| Glycopeptide resistanct is a primary concern for which microorganisms? |
|
Definition
| enterococcus and S. aureus |
|
|
Term
| Mechanisms of glycopeptide resistance: |
|
Definition
| altered target/ substitude D-lac for D-ala and vancomycin can no longer bind |
|
|
Term
| Beta-lactamase inhibitors do not affect which microorganisms? |
|
Definition
| pseudomonas or enterobacter |
|
|
Term
| List 2 beta-lactamase inhibitors and their relative beta-lactam drugs: |
|
Definition
- clavulanic (amoxicillin and ticarcillin)
- tazobactam (piperacillin)
|
|
|
Term
| List bacteria which can be inhibited by beta-lactamase inhibitors: |
|
Definition
- S. aureus
- H. influenza
- Niesseria sp.
- Bacteriodes fragillis
- E. Coli
- Klebsiella
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|
|
Term
| What does MLS stand for and what type of antibiotic are they? |
|
Definition
- stands for macrolide, licosamides, streptogramins
- protein synthesis inhibitor
|
|
|
Term
| List protein synthesise inhibiting antibioitics: |
|
Definition
- MLS
- aminoglycosides
- tetracyclines
- linezolid
|
|
|
Term
| Most common macrolide and what to look for to decide whether an antibiotic is a macrolide: |
|
Definition
- Erythromycin
- look for -mycin
|
|
|
Term
| What subunit of ribosome do macrolides bind to? |
|
Definition
|
|
Term
| Two mechanisms of action of macrolides include: |
|
Definition
- block growth of nascent peptide chain by stimulating dissociation of peptidyl-tRNA from ribosome
- inhibits assembly of new large ribosomal subunits (leads to depletion in cell)
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|
|
Term
| Macrolide resistance is caused by two (three kind of) mechanisms, what are they? What genes code for them? What phenotype? |
|
Definition
- Efflux pump coded by mef(A); M phenotype
- Target Site Modification erm(B); MLSB phenotype
- rRNA (MLS)
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|
|
Term
| Active Efflux resistance is resistance to which antibiotic only? |
|
Definition
|
|
Term
| is ribosomal modifications of macrolides inducive or constitutive? |
|
Definition
|
|
Term
| methylate adenine 2058 of 23s rRNA has to do with what antibiotic and what process? |
|
Definition
| macrolides (also MLSB phenotype) and process of ribosomal modification resistance (target site modification) erm(B) can be other letters |
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|
Term
| What are the 4 first choices of macrolide uses? |
|
Definition
- community acquired pneumoniae
- pertussis
- chlamydia trachomatis
- mycoplasma
|
|
|
Term
| What are 2 second choice uses of macrolides? |
|
Definition
| pyogenic streptococcal infections and C jejuni gastroentitis |
|
|
Term
| What is different about 2nd generation fluroquinolones? What mechanisms of action and name of drug. |
|
Definition
ciprofloxacin
- anti-pseudomonal and broader spectrum |
|
|
Term
What is different about 3rd generation fluroquinolones? What mechanisms of action and name of drug.
|
|
Definition
Moxifloxacin
- enhanced gram positive
+/- anaerobic |
|
|
Term
|
Definition
| protection of topoisomerase in fluroquinolone action |
|
|
Term
| How is acquired resistance to fluroquinolones achieved? |
|
Definition
| acquisition of resistance determinants from viridans streptococci |
|
|
Term
| First aminoglycoside and date? Are they natural? |
|
Definition
- streptomycin (1944)
- aminoglycosides are natural and semi-synthetic
|
|
|
Term
| Aminoglycoside activity against gram positive and negative? |
|
Definition
- excellent activity against gram negatives (including pseudomonas)
- good gram positive
|
|
|
Term
| When deciding if aminoglycoside or not? |
|
Definition
- look for -icin or just -cin
- ex. gentamicin, tobramicin, amikacin
|
|
|
Term
| Do aminoglycosides work in absesses? Why or why not? |
|
Definition
NO NO NO, do not work in any anaerobic conditions
they gain entry into inner membrane through energy dependent transport system - depend on the electron transport chain where O2 is needed |
|
|
Term
| What step of aminoglycoside action is rate limiting and by what? |
|
Definition
| the active transport through inner membrane is rate limiting and binding; blocked by divalent cations and anaerobiosis |
|
|
Term
| Is binding of aminoglycosides reversable or irreversable? What ribosomal subunit do they bind to? |
|
Definition
- irreversable
- bind to 30s (like tetracyclines)
|
|
|
Term
| What part of protein production does aminoglycosides inhibit? |
|
Definition
| proofreading; causes aberrant or truncated proteins |
|
|
Term
| Can aminoglycosides affect mammalian cells? |
|
Definition
| yes, at high concentrations it affects proteins (thats why it has a low therapeutic range with vancomycin!!) |
|
|
Term
| What are the three mechanisms of aminoglycoside resistance? |
|
Definition
- altered ribosomal binding site (streptomycin only)
- reduced uptake or decreased cell permeability
- enzymatic modification (most common)
|
|
|
Term
| What is the most common form of aminoglycoside resistance? |
|
Definition
enzymatic modification!
- >70 enzymes; plasmid mediated, different substrate specificities |
|
|
Term
| What drugs inhibit metabolic pathways? |
|
Definition
trimethoprim and sulfonamides
(TMP AND SMX)
SMX stands for sulfonamethoxazole |
|
|
Term
| TMP/SMX action against gram positive and negative |
|
Definition
| good gram negative, some gram positive |
|
|
Term
| sulfonamides act at what part of metabolic inactivation? |
|
Definition
| mimic PABA and stop transformation of PABA to dihydrofolic acid by tetrahydropteric acid synthetase |
|
|
Term
| trimethoprimes act at what part of metabolic inactivation |
|
Definition
inhibit dihydrofolate reductase
stops dihydrofolic acid from being tetrahydrofolic acid |
|
|
Term
| TMP/SMX is commonly used for uncomplicated what? |
|
Definition
|
|
Term
| What is TMP/SMX used against |
|
Definition
- common uncomplicated UTIs
- gastrointestinal infunction
- management of PCP pneumonia
- very active against anti-staphylococcal agents (CA-MRSA)
|
|
|
Term
| Mechanisms of metronidazole action |
|
Definition
short lived toxic intermediates or free radicals that damage DNA and other macromolecules
|
|
|
Term
| does metronidazole have a high or low bioavailability orally (PO) |
|
Definition
|
|
Term
| Does metronidazole have a long or short half life? |
|
Definition
|
|
Term
| side effects of metronidazole use |
|
Definition
- GI intolerance
- antibuse effect
- peripheral neuropathy
|
|
|
Term
| metronidazole resistance? price? |
|
Definition
- resistance slow to develope
- cheap
|
|
|
Term
|
Definition
- anaerobic infections
- C. Difficile colitis
- Giardiasis
- Trichmonas vaginitis and BV
- H pylori (in combination)
- parianal disease in IBD
|
|
|
Term
| define transglycocylation |
|
Definition
| the process where building blocks of peptidoglycan are added to the peptidoglycan backbone |
|
|
Term
| generations of cephalosporins are divided based on: |
|
Definition
|
|
Term
second generation cephalosporins are also known as:
3rd generation are: |
|
Definition
- 2nd gen: respiratory cephalosporins
- 3rd gen: IV drugs, gram neg activity, little gram pos
- 5th gen: taken off market
|
|
|
Term
| what worries people about VRE and MRSA in hospitals |
|
Definition
| VRE is resistant to drug that can be used against MRSA so scared that gene will transfer |
|
|
Term
| What is the best macrolide drug today? |
|
Definition
|
|
Term
| what macrolide drug is bad to take - rips gut and you have to take many doses a day? |
|
Definition
|
|
Term
| In terms of Target Site Modification and Efflux pumps (in macrolides), which gives you low level resistance and which gives you high level resistance? |
|
Definition
| efflux = low level; TSM = high level |
|
|
Term
| can you get resistance from down regulation of porin channels? |
|
Definition
| NO, if you have efflux AND downregulation you can though (these are acquired genes) |
|
|
Term
| why must mycoplasma be treated with macrolides? |
|
Definition
| because mycoplasma doesnt have a cell wall! - it causes lower pneumonia (microlids are used for lower tract infections - upper you use something else) |
|
|
Term
| Are fluroquinolones natural or synthetic? |
|
Definition
| completely and totally SYNTHETIC - not found in nature |
|
|
Term
| what were fluroquinolones first designed for? |
|
Definition
|
|
Term
| What kind of drug is a respiratory fluroquinolone? |
|
Definition
| Moxifloxacin and other 3rd gen ..? |
|
|
Term
| What are the best 2 drugs to treat patients with anaerobic infections? |
|
Definition
| metronidazole and clindamicin |
|
|
Term
| Can you take metronidazole and drink alcohol? |
|
Definition
| hell no sir. (violently sick) |
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