PHM 564 EU6; Antimicrobials, antifungals, chemo, antiviral
colonization - correct answer general flora found in non-sterile sites (not causing disease)
-staph and strep--> skin
-gram neg aerobic and anaerobic bacteria--> GI
-strep viridians and some anaerobes--> mouth and oropharynx
infection - correct answer -presence of bacteria is causing disease
-non-sterile sites have bugs that shouldn't be there
blood--> *staph and strep, gut bugs*
CSF--> *staph pneumoniae, H. influenza, strep*
Urine--> *gram - gut bugs, staph, strep*
Lungs--> S. pneumoniae
prophylaxis - correct answer -antibiotic selected to *prevent* infection
-useful in immunocompromised (long-term steroid use)
empiric - correct answer antibiotic to treat *suspected* pathogen
specific - correct answer antibiotic selected to treat *known* pathogen
outpatient organism identification - correct answer -based on epidemiologic patterns
-i.e. acute otitis media caused by moraxella, haemophilus, strep
inpatient organism identification - correct answer -cultures and susceptibility testing *before*
starting Ab
-Gram + cocci in spinal fluid;
-in NB--> most likely *group B strep*, which is sensitive to *PCN*
-in 40 yr old--> likely *strep pneumoniae*, which is almost always *resistant to PCN*; treat with
increased doses of *ceph and vanco*
MIC - correct answer -minimum inhibitory concentration
-lowest concentration of the ab that results in inhibition of visible growth under standard
conditions
MBC - correct answer -lowest concentration of ab that kills 99.9% of the original inoculum in a
given time
,breakpoint MIC - correct answer -concentration of ab that can be achieved in the bloodstream
with optimal therapy
-highest concentration that can be safely obtained
interpretation of susceptibility testing - correct answer sensitive = *MIC<breakpoint MIC*
intermediate = *MIC=breakpoint MIC*
resistant = *MIC>breakpoint MIC*
concentration-dependent killing - correct answer -peak levels determine adequacy of
treatment
-*higher the achieved concentration v. MIC, greater the effect* (aminoglycosides and
vancomycin)
-*greater the AUC:MIC ratio, greater the ab effect* (fluroquinolines)
time-dependent killing - correct answer -drug must achieve MIC at site of admin. & be
maintained to be effective (B-lactams)
-*longer [ab] > MIC, greater the effect
Post-antibiotic effect - correct answer -PAE
-suppression of microbial growth after [ab] falls below MIC
-*macrolides*; ab given for 5 days, works in body for 14 days
conditions affecting bioavailability - correct answer -great effect on *oral drugs*
-oral bioavailability affected by: increase/decrease in GI pH; decrease in integrity; decrease in
blood circulation to GI
-IV bioavail affected by: decreased BP/circulation; change in perfusion to organ
conditions affecting distribution - correct answer -fluid overload; ascites; heart failure; edema;
pregnancy--> increases Vd
-larger dose required
characteristics of ab that allow dosing to be the same - correct answer -good oral bioavail
-wider therapeutic index
-no adverse effects assoc. with peaks and troughs
-mainly time-dependent activity; as long as you are above the MIC, good to go
,characteristics of ABX that require dosing differences - correct answer -concentration-
dependent activity
-narrow TI
-Vd
-renal dosing
-site of infection
-weight-based
-toxic doses; monitor troughs and peaks
bacteriostatic - correct answer -able to inhibit essential metabolic processes and growth of
susceptible bacteria, *but not kill*
bacteriocidal - correct answer able to *kill* susceptible bacteria
cell wall synthesis - correct answer -targeted by many ab
-penicillin binding proteins include transpeptidase and transglycosylase
gram (+) wall - correct answer -thick cell wall, difficult to penetrate
-hydrophilic--> ab must be hydrophilic to cross gram (+) cell wall
gram (-) wall - correct answer -lipophilic outer membrane
-large molecules cannot penetrate
-porin channel: H2O-filled; small, hydrophilic drugs can pass through
general mechanism of actions - correct answer -metabolism inhibitors (sulfonamides,
trimethoprim)
-cell wall synthesis inhibitors (B-lactams, vanco)
-protein synthesis inhibitors (aminoglycosides, macrolides, clindamycin, chloramphenicol)
-nucleic acid function/synthesis inhibitors (fluoroquinolones, rifampin)
-cell membrane function inhibitors (isoniazid, amphotericin B)
cell wall synthesis inhibitors - correct answer -B-lactams; penicillins, ceph, carbapen,
monobactam, vanco/dalbavancin/televancin/oritavancin, bacitracin
plasma membrane disrupters - correct answer daptomycin
30S ribosome inhibitors - correct answer -aminoglycosides
, -tetracyclines
-tigecycline
50S ribosome inhibitors - correct answer -macrolides
-clindamycin
-linezolid, tedizolid
-quinopristin-dalfopristin
inhibit DNA replication - correct answer -fluoroquinolones
-metronidazole
inhibits RNA synthesis - correct answer -rifampin
inhibit enzyme activity - correct answer -sulfonamides
-trimethoprim
synergism - correct answer -2 or more agents working together to allow a dosage reduction
and/or faster/enhanced drug effect
-different MOAs
-can both penetrate the site of infection
-both have a similar spectrum of activity
antagonism - correct answer -when 1 agent interferes with the effects of another agent,
decreasing the activity and potentially leading to treatment failure
allergy to ab - correct answer -immune response, causes damage to normal tissues
-documented *Steven's Johns Syndrome* or *Toxic Epidermal Necrolysis* to an ab--> never try
ab again
sensitivity to ab - correct answer -adverse effect that is not immune-mediated; upset stomach,
lightheadedness, dry mouth, cough
B-lactam antibiotics - correct answer -PCN, ceph, carbapenems, monobactam
-bind PBPs (inner surface on cell wall)
-blocks transpeptidation reaction (necessary for x-linking)
-osmotic fragility and cell lysis
-effects greatest on actively replicating organisms
colonization - correct answer general flora found in non-sterile sites (not causing disease)
-staph and strep--> skin
-gram neg aerobic and anaerobic bacteria--> GI
-strep viridians and some anaerobes--> mouth and oropharynx
infection - correct answer -presence of bacteria is causing disease
-non-sterile sites have bugs that shouldn't be there
blood--> *staph and strep, gut bugs*
CSF--> *staph pneumoniae, H. influenza, strep*
Urine--> *gram - gut bugs, staph, strep*
Lungs--> S. pneumoniae
prophylaxis - correct answer -antibiotic selected to *prevent* infection
-useful in immunocompromised (long-term steroid use)
empiric - correct answer antibiotic to treat *suspected* pathogen
specific - correct answer antibiotic selected to treat *known* pathogen
outpatient organism identification - correct answer -based on epidemiologic patterns
-i.e. acute otitis media caused by moraxella, haemophilus, strep
inpatient organism identification - correct answer -cultures and susceptibility testing *before*
starting Ab
-Gram + cocci in spinal fluid;
-in NB--> most likely *group B strep*, which is sensitive to *PCN*
-in 40 yr old--> likely *strep pneumoniae*, which is almost always *resistant to PCN*; treat with
increased doses of *ceph and vanco*
MIC - correct answer -minimum inhibitory concentration
-lowest concentration of the ab that results in inhibition of visible growth under standard
conditions
MBC - correct answer -lowest concentration of ab that kills 99.9% of the original inoculum in a
given time
,breakpoint MIC - correct answer -concentration of ab that can be achieved in the bloodstream
with optimal therapy
-highest concentration that can be safely obtained
interpretation of susceptibility testing - correct answer sensitive = *MIC<breakpoint MIC*
intermediate = *MIC=breakpoint MIC*
resistant = *MIC>breakpoint MIC*
concentration-dependent killing - correct answer -peak levels determine adequacy of
treatment
-*higher the achieved concentration v. MIC, greater the effect* (aminoglycosides and
vancomycin)
-*greater the AUC:MIC ratio, greater the ab effect* (fluroquinolines)
time-dependent killing - correct answer -drug must achieve MIC at site of admin. & be
maintained to be effective (B-lactams)
-*longer [ab] > MIC, greater the effect
Post-antibiotic effect - correct answer -PAE
-suppression of microbial growth after [ab] falls below MIC
-*macrolides*; ab given for 5 days, works in body for 14 days
conditions affecting bioavailability - correct answer -great effect on *oral drugs*
-oral bioavailability affected by: increase/decrease in GI pH; decrease in integrity; decrease in
blood circulation to GI
-IV bioavail affected by: decreased BP/circulation; change in perfusion to organ
conditions affecting distribution - correct answer -fluid overload; ascites; heart failure; edema;
pregnancy--> increases Vd
-larger dose required
characteristics of ab that allow dosing to be the same - correct answer -good oral bioavail
-wider therapeutic index
-no adverse effects assoc. with peaks and troughs
-mainly time-dependent activity; as long as you are above the MIC, good to go
,characteristics of ABX that require dosing differences - correct answer -concentration-
dependent activity
-narrow TI
-Vd
-renal dosing
-site of infection
-weight-based
-toxic doses; monitor troughs and peaks
bacteriostatic - correct answer -able to inhibit essential metabolic processes and growth of
susceptible bacteria, *but not kill*
bacteriocidal - correct answer able to *kill* susceptible bacteria
cell wall synthesis - correct answer -targeted by many ab
-penicillin binding proteins include transpeptidase and transglycosylase
gram (+) wall - correct answer -thick cell wall, difficult to penetrate
-hydrophilic--> ab must be hydrophilic to cross gram (+) cell wall
gram (-) wall - correct answer -lipophilic outer membrane
-large molecules cannot penetrate
-porin channel: H2O-filled; small, hydrophilic drugs can pass through
general mechanism of actions - correct answer -metabolism inhibitors (sulfonamides,
trimethoprim)
-cell wall synthesis inhibitors (B-lactams, vanco)
-protein synthesis inhibitors (aminoglycosides, macrolides, clindamycin, chloramphenicol)
-nucleic acid function/synthesis inhibitors (fluoroquinolones, rifampin)
-cell membrane function inhibitors (isoniazid, amphotericin B)
cell wall synthesis inhibitors - correct answer -B-lactams; penicillins, ceph, carbapen,
monobactam, vanco/dalbavancin/televancin/oritavancin, bacitracin
plasma membrane disrupters - correct answer daptomycin
30S ribosome inhibitors - correct answer -aminoglycosides
, -tetracyclines
-tigecycline
50S ribosome inhibitors - correct answer -macrolides
-clindamycin
-linezolid, tedizolid
-quinopristin-dalfopristin
inhibit DNA replication - correct answer -fluoroquinolones
-metronidazole
inhibits RNA synthesis - correct answer -rifampin
inhibit enzyme activity - correct answer -sulfonamides
-trimethoprim
synergism - correct answer -2 or more agents working together to allow a dosage reduction
and/or faster/enhanced drug effect
-different MOAs
-can both penetrate the site of infection
-both have a similar spectrum of activity
antagonism - correct answer -when 1 agent interferes with the effects of another agent,
decreasing the activity and potentially leading to treatment failure
allergy to ab - correct answer -immune response, causes damage to normal tissues
-documented *Steven's Johns Syndrome* or *Toxic Epidermal Necrolysis* to an ab--> never try
ab again
sensitivity to ab - correct answer -adverse effect that is not immune-mediated; upset stomach,
lightheadedness, dry mouth, cough
B-lactam antibiotics - correct answer -PCN, ceph, carbapenems, monobactam
-bind PBPs (inner surface on cell wall)
-blocks transpeptidation reaction (necessary for x-linking)
-osmotic fragility and cell lysis
-effects greatest on actively replicating organisms
