Term
| Are antibiotics from biological or synthetic sources? |
|
Definition
| prototype from biological source |
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|
Term
| Are antimicrobials from biological or synthetic sources? |
|
Definition
|
|
Term
| What is selective toxicity? |
|
Definition
| Ability of the antimicrobial agent to exploit some difference between bacteria and human cells to provide effective antibacterial action with minmal or tolerable toxicity. |
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Term
| What is antimicrobial switching? |
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Definition
| predetermined change in empiric therapy |
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|
Term
| What is antimicrobial switch therapy? |
|
Definition
| change in route of administration |
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Term
| Sulfonamides belong to what class? |
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Definition
|
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Term
|
Definition
| Inhibitor of folate synthesis |
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Term
| What does trimethoprim/pyrimethamine do? |
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Definition
| inhibitors of folate reduction |
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Term
| Sulfonamides inhibit what? |
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Definition
| Sulfonamides prevents PABA incorporation in folic acid, which in essential for bacterial growth. It is a competitive inhibitor of dihydropteroate synthesis |
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Term
| What spectrum of action are sulfonamides? |
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Definition
| Broad spectrum, but resistance severely limits actual clinical spectrum |
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Term
| Do sulfonamides penetrate the placental and BBB? |
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Definition
|
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Term
| How are sulfonamides eliminated? |
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Definition
| Eliminated in urine. Primary indication for drug is for UTIs. |
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Term
| 4 major adverse effects of sulfonamides |
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Definition
| 1. Hypersensitives (Steven-Johnsons syndrome) 2. kernicterus in newborns 3. Blood problems (anemia in G6PD) 4. crystal formation in urine |
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Term
| What is Stevens-Johnson syndrome? |
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Definition
| fever, malaise, erythma multiforme, ulceration of mucus membranes |
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Term
|
Definition
| Compound gets concentrated in brain-enhanced reflexes- only newborns Landmark feature-high pitched squeal |
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Term
| What Sulfonamide is used for UTIs? |
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Definition
|
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Term
| Sulfonamide used for ophthalmic and topical infections |
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Definition
|
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Term
| Sulfonamide used for topical infections and burns |
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Definition
|
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Term
| Mechanism of action for Trimethoprim and Pyrimethamine |
|
Definition
| inhibition of dihydrofolate reductase |
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Term
| Why put sulfonamides with trimethoprim and pyrimethamine? |
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Definition
| They provide a sequential blockade of folate synthesis. |
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Term
| Can trimethoprim and pyrimethamine penetrate the BBB? |
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Definition
| Yes, if inflammation is present. |
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Term
| Trimethoprim/Sulfamethoxazole is drug of choice for what? |
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Definition
| Prophylaxis for recurrent UTI and Pneumocystitis carnii infections |
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Term
| Pyrimethamine-sulfadoxine is used for what? |
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Definition
| Malaria treatment and prevention |
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Term
| What 3 types of patients do you need to avoid use of Trimethoprim and Pyrimethamine in? |
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Definition
| 1. Blood dyscrasias 2. Hepatic damage 3. Renal impairment -all are minimized with folic acid supplemenation |
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Term
| What do you need to supplement the patient with when placed on Trimethoprim or Pyrimethamine? |
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Definition
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Term
|
Definition
| Forms a reactive nitro group which forms oxides and superoxides (free radicals)-attack membranes and DNA |
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Term
| What is the spectrum of action of Nitrofurans? |
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Definition
|
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Term
| What type of pulmonary reactions form when using long term therapy with Nitrofurans? |
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Definition
| Acute pneumonia and interstitial fibrosis-make sure to get CXR on regular basis. |
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Term
| Long term use of Nitrofurans with a patient that has renal impairment could cause what? |
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Definition
|
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Term
| What do you use Nitrofurantoin for? |
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Definition
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Term
| How do fluoroquinolone agents work? |
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Definition
| Fluroquinolones blocks DNA synthesis by inhibiting topoisomerase (DNA gyrase) II and IV |
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Term
| What drug can block elimination by tubular secretion of Fluoroquinolones? |
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Definition
|
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Term
| Major adverse effects of Fluoroquinolones |
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Definition
| Anemia, nephrotoxicity, CNS effects, cartilage effects ("lones hurt connections to bones") |
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Term
| 1st generation fluroquinolones spectrum of action |
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Definition
|
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Term
| 2nd-4th Fluorquinolones spectrum of action |
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Definition
| Increased gram - & +, 4th generation has anaerobic coverage |
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Term
| Name of 1st generation fluoroquinolone agent |
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Definition
|
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Term
| Names of the two 2nd generation fluoroquinolone agents |
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Definition
| 1. Norfloxacin 2. Ciprofloxacin (most powerful) |
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|
Term
| 1 of main indications of Ciprofloxacin |
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Definition
|
|
Term
| Names of 3rd generation fluoroquinolones (2) |
|
Definition
| 1. Levofloxacin 2. Gatifloxacin |
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|
Term
| Name of 4th generation fluoroquinolone |
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Definition
|
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Term
| Mechanism of action for Methenamine |
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Definition
| Converted to formeldahyde in acidic urine of pH of 5.5 or less-this is toxic to bacteria |
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|
Term
| What is Methenamine used to treat? |
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Definition
| Chronic suppressive therapy or recurrent UTI by susceptible bacteria. |
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|
Term
| Can you use Methenamine in patients with hepatic dysfunction? |
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Definition
| No, because it causes elevated ammonia levels |
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|
Term
| Can you use Methenamine with sulfonamides? |
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Definition
| No, sulfonamides react with formeldahyde. |
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|
Term
| What is the outer layer made of in gram positive organisms? |
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Definition
|
|
Term
| What is the outer later in gram negative organisms? |
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Definition
| LPS membrane with narrow channel porins |
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Term
| What is the 1st step in cell wall synthesis? |
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Definition
| Precursor is synthesized. |
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Term
| What is the 2nd step in cell wall synthesis? |
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Definition
| Formation of sugar-pentapeptide, its transport of membrane and subsequent addition and polymerizaiton to linear peptidoglycan strands. |
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Term
| What is the 3rd step of cell wall synthesis? |
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Definition
| Cross linking of adjacent peptidoglycan strands by a transpeptidase reaction |
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Term
| What is the mechanism of action for Vancomycin? |
|
Definition
| Inhibition of cell wall synthesis at step 2. |
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|
Term
| What is spectrum of action for Vanco? |
|
Definition
| Gram positive-most commonly drug resistant gram pos like MRSA, MRSE, C. diff |
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|
Term
| What is the mechanism of resistance for Vanco? |
|
Definition
| plasmid-based replacement of terminal D-ala with D-lac and reduced affinity |
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Term
| Why is it important to get the patient's renal status before starting treatment with vanco? |
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Definition
| t1/2 is 5-11 hours with normal renal function t1/2 is 7-9 days with renal dysfunction |
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|
Term
| What drug is associated with possible irreversible ototoxicity? |
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Definition
|
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Term
| What drug is "Red-man" syndrome associated with? How can it be prevented? |
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Definition
| Associated with vancomycin, most commonly in presence of anesthetic. To prevent this, wait 12 hours post surgery to start vanco therapy. |
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Term
| "Gorillacillin" is another name for what medication? |
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Definition
|
|
Term
| What is mechanism of action for Bacitracin? |
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Definition
| Binds to lipid pyrophosphate carrier to inhibit cell wall synthesis (step 2). |
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Term
| What is an adverse effect if Bacitracin reaches systemic levels? |
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Definition
|
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Term
| What are the 3 mechanisms of action for Beta-lactam antibiotics? |
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Definition
| 1. Binds to PBPs 2. Blocks transpeptidase crosslinking of cell wall components (step 3 of cell wall synthesis) 3. Activates autolytic enzymes |
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Term
| Are B-lactam antibiotics cidal or static? |
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Definition
|
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Term
| Why is the "R" group important in B-lactam antibiotics? |
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Definition
| The R group protects the beta-lactam ring. If the ring is opened, the bacteria can gain resistance. |
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Term
| What is the overall effect of B-lactam antibiotics? |
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Definition
| They result in weakened cell wall, aberrant morphological form, cell lysis, and death. |
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Term
| What are the forms of resistance against b-lactam antibiotics? |
|
Definition
| B-lactamse, penicillinase, cephalosporinase |
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|
Term
| Can penicillin cross the BBB? |
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Definition
| Only when inflammation if present |
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|
Term
| What can block excretion of Penicillin? |
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Definition
| Probenacid can block the tubular secretion of penicillin. |
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Term
| What 3 penicillins are eliminated by biotransformation? |
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Definition
| Naficillin, Ampicillin, Piperacillin-must adjust dose of these if patient has hepatic dysfunction. |
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Term
| What is the spectrum of action for Penicillins? |
|
Definition
|
|
Term
| What is Penicillin the drug of choice for? |
|
Definition
| Treatment of choice for prophylaxis of syphilis. |
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|
Term
| What is the spectrum of action for anti-staph penicillins? |
|
Definition
| very narrow gram positive |
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|
Term
| What is unique about elimination with the anti-staph penicllins? |
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Definition
| Elimination is by a combination of hepatic and renal mechanisms |
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|
Term
| Aminopenicillins are the drug of choice for what? |
|
Definition
| Aminopenicillins are drugs of choice for preventing endocarditis with surgical or dental procedures. |
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|
Term
| What are the names of the two aminopenicillins? |
|
Definition
| Ampicillin and Amoxicillin |
|
|
Term
| What area of the body does ampicllin reach therapeutic levels? |
|
Definition
| Ampicillin reaches therapeutic levels in the CSF in meningitis, making it an effective treatment for meningitis. |
|
|
Term
| What is the spectrum of action for antipsuedopenicillins? |
|
Definition
| Extended/broad spectrum of action |
|
|
Term
| Do B-lactamase inhibitors have any antimicrobial actions? |
|
Definition
| No, the bind to b-lactamase enzymes (irreversible inhibitors) |
|
|
Term
| Would you use b-lactamase inhibitors with anti-staph penicillins? |
|
Definition
|
|
Term
| Does previous success with penicillins dictate future success? |
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Definition
| No, reactions to penicillins are always possible. |
|
|
Term
| What do you give to a pregnant women with syphilis if she is allergic to penicillin? |
|
Definition
| Penicillin. Do as inpatient and watch carefully. |
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|
Term
| Adverse reactions to penicillins are more common with what virus? |
|
Definition
|
|
Term
| What adverse reaction do penicillins commonly cause in newborns? |
|
Definition
| Vitamin K deficiency-coagulation disorders |
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|
Term
| Will aztreonam cause a reaction in patients who have a type 1 reaction to penicillins? |
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Definition
| No. Patients with Type 1 reactions to penicillins need to avoid all beta lactams EXCEPT aztreonam. |
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Term
| When dealing with cephalosporins, does gram negative activity increase or decrease when moving from 1st to 4th generation? |
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Definition
| Gram-negative activity increases from 1st to 4th generations |
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|
Term
| Does gram-positive activity increase or decrease when moving from 1st to 4th generation cephalosporins? |
|
Definition
| Gram-positive activity decreases when moving from 1st to 4th generation |
|
|
Term
| Is there increased or decreased resistance to B-lactamases when moving from 1st to 4th generation cephalosporins? |
|
Definition
| There is an increased resistance to B-lactamases when moving from 1st to 4th generation cephalosporins |
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|
Term
| True or False: Cephalosporins are generally used when penicillins or other less expensive drugs fail |
|
Definition
|
|
Term
| What is the treatment of choice for gram-negative meningitis? |
|
Definition
| 3rd generation cephalosporin |
|
|
Term
| What is the drug of choice for prophylaxis of gonorrhea? |
|
Definition
| Ceftriaxone (3rd generation cephalosporin) |
|
|
Term
| What are the names of the 3 cephalosporins that produce a dangerous interaction with alcohol? |
|
Definition
| 1. Cefotetan 2. Cefoperazone 3. Cefmetazole |
|
|
Term
| True or False: There is no cross reactivity between cephalosporins and penicillins |
|
Definition
| False. 100% Cross-reactivity should be assumed, but it is incomplete. |
|
|
Term
| What is the name of the Carbapenem that has the broadest spectrum of action with low susceptibility to b-lactamases? |
|
Definition
|
|
Term
| Why is cilastatin added to Imipenem |
|
Definition
| Cilastatin prevents inactivation by renal dehydropeptidase-1. |
|
|
Term
| True or False: Imipenem with cilastatin does not share cross reactivity with penicillin or cephalosporin-sensitive patients |
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Definition
| False, there is 100% cross reactivity. |
|
|
Term
| What is the drug of choice for treating Enterobacter? |
|
Definition
|
|
Term
| What medication has a high incidence (~1%) of seizures? |
|
Definition
|
|
Term
| How is Meropenem different from Imipenem? |
|
Definition
| Meropenem is not biotransformed by dehydropeptidase and not as likely to produce seizures. |
|
|
Term
| What is the spectrum of action for Aztreonam? |
|
Definition
| Gram-negative spectrum of action |
|
|
Term
| What is the mechanism of action for Polymyxin? |
|
Definition
|
|
Term
| True or False: Polymyxin B is usually given in systemic doses. |
|
Definition
| False, systemic doses cause nephro and neurotoxicites |
|
|
Term
| What is the mechanism of action for Daptomycin? |
|
Definition
| Daptomycin binds membranes or gram positive bacteria causing rapid depolarization leading to cell death. |
|
|
Term
| What is the spectrum of action for Daptomycin? |
|
Definition
|
|
Term
| What are 2 important adverse reactions of Daptomycin? |
|
Definition
| 1. Myopathy 2. Peripheral Neuropathy |
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