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71 Cards in this Set
- Front
- Back
Characteristics of gram + bacteria
|
thick peptidoglycan layer
no periplasmic space no outer membrane low lipidsaccharide |
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Characteristics of gram - bacteria
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thin peptidoglycan layer
have outer membrane periplasmic space |
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Staphylcocci
Staph aureus |
Gram +
|
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Streptococci
Stretococcus pneumoniae enterococci |
gram +
|
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clostridium difficile
|
gram +
anaerobe |
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Pseudomonad
Psudomonas aeruginosa |
gram -
|
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Acinetobacter
acinetobacter boumannii |
gram -
|
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Bacteroides fragilis
|
gram -
anaerobe |
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Legionella
|
gram -
aerobic |
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Enterobacteriaceae
Escherichia Coli Kiebsiella |
gram -
|
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Penicillins
Class? MOA? Bacteriocidal or bacteriostatic? |
Beta lactam
Bacteriocidal Targets PBP like transpeptidase= no x-linking=no cell wall sx= cell lysis |
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Cephalosporins
Class? MOA? Bacteriocidal or bacteriostatic? |
Beta lactam
Bacteriocidal Targets PBP like transpeptidase= no x-linking=no cell wall sx= cell lysis |
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Monobactams
Class? MOA? Bacteriocidal or bacteriostatic? |
Beta lactam
Bacteriocidal Targets PBP like transpeptidase= no x-linking=no cell wall sx= cell lysis |
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Carbapenems
Class? MOA? Bacteriocidal or bacteriostatic? |
Beta lactam
Bacteriocidal Targets PBP like transpeptidase= no x-linking=no cell wall sx= cell lysis |
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Vancomycin
Class? MOA? Bacteriocidal or bacteriostatic? |
Bacteriacidal
Inhibits cell wall sx Target: binds D-ala-D-ala of glycan chain, blocks transglycosylase rxn, no new glycan chains incorporated= inhibits cell wall sx |
|
Nalidixic acid
ciprofloxacin levofloxacin gemifloxacin Class? MOA? Bacteriocidal or bacteriostatic? |
quinolones; Bactericidal
Inhibit type II topoisomerases- DNA gyrase in gram - and topoisomerase IV in gram + |
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Metronidazole
Class? MOA? Bacteriocidal or bacteriostatic? |
bactericidal
prodrug activated to radical which damages DNA and prevents replication. activated by ferrodoxin |
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streptomycin
gentamycin tobramycin amikacin Class? MOA? Bacteriocidal or bacteriostatic? |
aminoglycosides, bactericidal
Binds to 30S and blocks initiation of protein sx; causes misreading of mRNA and wrong amino acids get put into protein; or misread causes premature termination. Membrane uses bad proteins and increases permeability= death |
|
Erthromycin
Clarithromycin Telithromycin Class? MOA? Bacteriocidal or bacteriostatic? |
Macrolides; bacteriostatic
reversibly inhibit protein sx by binding to 50S ribosome subunit |
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Doxycycline
minocycline Class? MOA? Bacteriocidal or bacteriostatic? |
tetracyclines; bacteriostatic
reversibly inhibit protein sx by binding to 30 S ribosome subunit and blocking entrance of tRNA |
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Clindamycin
Class? MOA? Bacteriocidal or bacteriostatic? |
bacteriostatic
reversibly inhibit protein sx by binding to 50S ribosome subunit |
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Sulfamethoxazole
Class? MOA? Bacteriocidal or bacteriostatic? |
sulfonamide; bacteriostatic
acts as antimetabolite by competing with PABA for dihydropteroate synthase and inhibits folate sx |
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Cycloserine
Class? MOA? Bacteriocidal or bacteriostatic? |
bacteriostatic
inhibits cell wall sx by inhibition of D-ala racemase and ligases |
|
Methods of resistance for
Beta lactams (3) |
Reduced affinity of drug for PBP
Decreased uptake or increased efflux Beta lactamase inactivate beta lactam |
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Clavulanic acid
MOA |
beta lactamase inhibitor used with amoxicillin or ticarcillin
|
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Sulbactam
MOA |
beta lactamase inhibitor used with ampicillin (Unasyn)
|
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Tazobactam
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beta lactamase inhibitor used with piperacillin (Zosyn)
|
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Augmentin
|
clavulanic acid + amoxicillin
|
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Timentin
|
ticarcillin + clavulanic acid
|
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Unasyn
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sulbactam + ampicillin
|
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Zosyn
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tazobactam + piperacillin
|
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Spectrum of coverage for penicillins
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G: gram +
Oxacillin/ naficillin: +, some - Amox/ampicillin: more - ticarcillin, piperacillin, mealocillin: most - |
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Penicillin drug interactions
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Birth control- less bacteria= less enterohepatic circulation= less estrogen
methotrexate: both compete for renal tubular secretion probenecid: inhibits pcn secretion transporter in proximal tubule |
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cefazolin
Gen? spectrum? |
1st gen cephalosporin
excellent + modest - |
|
cefuroxime
gen? spectrum? |
2nd gen cephalosporin
less + than 1st more - than 1st some anaerobes |
|
cefoxitin
gen? spectrum? |
2nd gen cephalosporin
less + than 1st more - than 1st some anaerobes |
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cefotetan
gen? spectrum? |
2nd gen cephalosporin
less + than 1st more - than 1st some anaerobes |
|
Cephalosporin
MOA |
beta lactam
inhibits cell wall sx by PBP; inhibits transpeptidase and x linking rxn |
|
cefdinir
gen? spectrum? |
3rd gen cephalosporin
excellent + more - than 2nd |
|
ceftriaxone
gen? spectrum? |
3rd gen cephalosporin
excellent + more - than 2nd |
|
ceftazidime
gen? spectrum? |
3rd gen cephalosporin
excellent + more - than 2nd |
|
cefepime
gen? spectrum? |
4th gen cephalosporin
excellent + more - than 3rd broadest spectrum least sensitive to beta lactamases |
|
Aztreonam
MOA Spectrum Class |
Monobactam; beta lactam- inhibits cell sx thru PBP
Narrow gram - only NO cross hypersensitivity w/ other b-lactams |
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Imipenem
MOA Spectrum Class |
Carbapenam; beta lactam
Broad spectrum |
|
Primaxin
What? Why? |
Imipenem + cilastatin
Cilastatin inhibits renal dehydropeptidase which hydrolyzes imipenem |
|
Bacitracin
MOA Spectrum |
Inhibits stage 3 of cell wall sx; inhibits dePO4lation of lipid carrier so precursors can't be transfered to membrane and incorporated into glycan chain. Prevents polymerization of glycan
Narrow gram + Nephrotoxic; topical only |
|
Cycloserine
MOA Spectrum |
inhibits D-ala racemase and ligase; inhibits cell wall sx
Broad spectrum CNS toxicity |
|
Fosfomycin
MOA Spectrum |
binds and inhibits enolpyruvate transferase
blocks sx of peptidoglycan precursors (stage 1) and inhibits cell wall sx Broad spectrum |
|
Vancomycin
MOA Spectrum |
Binds to D-ala terminal of glycan chain and blocks transglycosylase rxn; inhibits polymerization and cell wall sx
Narrow, gram + ototoxicity nephrotoxicity Red man syndrome |
|
Methods of resistance:
Vancomycin |
Enzymes switch from D-ala_D-ala to D-ala_D-lactate
reduced binding affinity |
|
Daptomycin
MOA Spectrum |
Binds to membrane phospholipids in a Ca2+ dependent manner and forms a pore in the membrane. Causes an efflux of K+ out of; similar to a detergent.
Spectrum like vanco (gram +) Myopathy |
|
Colistin
Polymyxin B MOA Spectrum |
Binds phospholipids, disrupts membrane like cationic detergent
Narrow, gram - nephrotoxicity |
|
Quinupristin
Dalfopristin Class MOA Resistance |
streptogramins; Synercid
Q:Bind to 50S ribosome subunit and block transpeptidation D: 50S binding site; enhances binding of Q Bactericidal together b/c of synergistic effect Resistance: Q: induces methylase to alter drug target; inactivated by lactonases D: increased efffluc; inactivated by acetyltransferase |
|
Linezolid
MOA Resistance |
oxazoladinones; bacteriostatic- reversibly inhibits protein sx:
Binds to P site of 50S ribosomal subunit and prevents formation of fmet-tRNA complex, blocking initiation altered binding site on target (ribosome)- low cross resistance gram + |
|
Spectinomycin
MOA Resistance |
spectinomycin; reversibly inhibits protein sx
Binds to 30S and prevents initiation Altered binding site; enzyme inactivation by adenylyltransferase narrow, gram - |
|
Tetracyclines
Adverse effects |
GI, hepatotoxiciy, deposits in calcifying tissues (brown teeth), photosensitive, chelator, preg cat. D
|
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Tetracyclines
Methods of resistance |
Induce ribosomal protection protein that displaces drug from binding site
decreased uptake and increased efflux enzymatic inactivation |
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Macrolides
Methods of resistance |
alter 50S ribosome target by inducing methylase enzymes or xsome mutation
increased efflux induces esterases hydrolyze macrolide drugs |
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Macrolides
adverse effects |
Gi, cardiac arrhythmias, hepatotoxiciy, azithromycin Al and MG antacids reduce plasma levels
|
|
Macrolides
drug interactions |
Inhibit CYP3A4- erythromycin, clrithromycin, telithromycin
NOT azithromycin |
|
Clindamycin
Methods of resistance |
alter 50S ribosome target by methylase expression. causes cross-resistance to macrolides
NOT a substrate for efflux |
|
Aminoglycosides
Spectrum? Methods of resistance? |
Narrow, aerobic gram -
Mutations alter drug target decreased uptake enzymatic inactivation |
|
Aminoglycosides
Adverse effects |
ototoxicity
nephrotoxicity preg cat D SYNERGISTIC with beta-lactams |
|
Nitrofurantoin
MOA Spectrum |
bacteria flavoproteins reduce it to reactive intermediates that damage DNA
Broad spectrum Contraindicated at 38 weeks gestation |
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Quinolones
Methods of Resistance |
mutations alter DNA gyrase or topoisomerase IV
mutations reduce membrane permeability and decrease uptake |
|
Quinolones
Spectrum |
gram -: DNA gyrase
gram + : topoisomerase IV |
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Quionolones
Adverse effects |
GI, CNS (HA, dizzy), Achilles tendon rupture or tendonitis (BLACK BOX), QT interval prolongation. photosensitivity
Contraindicated in peds (arthropathy) |
|
Metronidazole
Spectrum Adverse effects |
anaerobic protozoa
anaerobic bacteria disulfram rxn with alcohol |
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Trimethoprim
MOA |
Inhibits Dihydrofolate reductase, acting as antimetabolite so bacteria can't make folate = no DNA sx (sequential inhibition when combined w/ sulfamethoxazole= synergistic)
|
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Bactrim
Resistance? |
Sulfamethoxazole and trimethoprim
Reduced binding affinity of dihydropteroate synthase or DHFR decreased uptake increased PABA or DHFR |
|
ADEs Linezolid
|
thrombocytopenia
periph neuropathy serotonin syndrome lactic acidosis optic neuritis |