Infectious Disease pt 1 Flashcards
Gram + bugs will stain ______
Gram - bugs will stain ______
\+ = purple/blue - = red/pink
what are some mechanisms of resistance?
intrinsic (natural) selection pressure (resistant bacteria remain behind) enzyme inactivation
examples of beta lactamase inhibitors?
clavulanate
sulbactam
tazobactam
avibactam
what bug is the most common CRE (carbapenem resistant enterobactieracae)
klebsiella
T or F: All abx have risk for C.Diff infection
true
what abx are folic acid synthesis inhibitors
sulfonamides
trimethoprim
dapsone
what abx are cell wall inhibitors
beta lactams (PCNs, cephalosporins, carbapenems)
Monobactams
Vancomyocin, dalbavancin, telavancin, oritavancin
what abx are DNA/RNA inhibitors
quinolones
metronidazole/tinidazole
Rifampin
what abx are cell membrane inhibitors
polymyxin
daptomycin
telavancin
oritavancin
what abx are protein synthesis inhibitors
aminoglycosides macrolides tetracyclines clindamycin linezolid/tedizolid quinupristin/dalfopristin
(Lipophillic or hydrophilic) drugs usually have enhanced penetration of bone, lung, and brain tissue
lipophillic
(Lipophillic or hydrophilic) is renal eliminated and thus can be nephrotoxic
hydrophilic
(Lipophillic or hydrophilic) has hepatic metabolism and thus can be hepatoxic/has drug drug interactions
lipophilic
(Lipophillic or hydrophilic) has increased clearance and/or distribution in sepsis and will probably need to do larger doses during sepsis
hydrophilic
(Lipophillic or hydrophilic) has excellent bioavailability and thus PO:IV ratio is 1:1
lipophilic
(Lipophillic or hydrophilic) has small volume of distribution and thus poor tissue penetration
hydrophilic
(Lipophillic or hydrophilic) gets intracellularly and thus is active against atypical pathogens
hydrophilic
what drugs are hydrophilic
beta lactam aminoglycosides glycopeptides daptomyocin colistimethate
what drugs are lipophilic
quinolones macrolides rifampin linezolid tetracyclines chloramphenicol
what ways can you maximize the pharmacodynamics of beta lactam abx
more frequent dosing/shorter drug interval
extending the infusion time
give as a continuous infusion
what drugs are time dependent (time>MIC) and what is the PD goal?
beta lactams (PCNs, cephalosporins, carbapenems)
Goal: keep drug level above the MIC for most of the dosing interval
what drugs’ PD is AUC:MIC?
what what is the PD goal?
vancomycoin, macrolides, tetracyclines, colistimethate
Goal: exposure over time
what drugs PD is Cmax: MIC (concentration dependent)
and what is the PD goal?
aminoglycosides, quinolones, daptomyocin
Goal: high peak = killing and low trough = less toxicity
beta lactamase inhibitors add ______ and _____ coverage
gram - and anaerobe
what bug does PCN notably cover
streptococci
what is the IM form of PCN?
PCN benzathine
PCN procaine
ADEs of PCN?
GI upset
rash
Seizure with accumulation
Amoxicillin and Augmentin can come in ______ dosage forms (that others do not)
chewable
Pip/tazo usually administered over what amount of time to increase time > MIC?
4 hours
What is oral PCN used for the most?
strep throat
or
mild (non purulent) skin infections
What is oral Amoxicillin commonly used for?
otitis media (80 - 90 mg/kg/day)
infective endocarditis prophylaxis before dental procedures
Used in H.pylori infections
What is oral Amoxicillin/Clavulanate commonly used for?
otitis media/sinus infection (90 mg/kg/day)
important dosing consideration for amox/clav
use product with the least amount of clavulanate to decrease diarrhea side effects
what is IM PCN benzathine commonly used for?
drug of choice for syphillis - IM for one dose
PCN benzathine should NOT be given via _____ because it can cause death
IV
Pip/tazo is able to cover _____ unlike most other PCNs
pseudomonas
What PCNs cover MSSA but not MRSA?
nafcillin
oxacillin
dicloxacillin
Which PCNs do NOT need renally adjusted?
nafcillin/oxacillin
dicloxacillin
1st generation cephalosporins cover gram ____ cocci well and are best for _____ infections
gram + cocci
MSSA infections
1st gen cephs cover what gram - rods
PEK
proteus, E.coli klebsiella
2nd gen cephs are split into two groups
Drugs like cefuroxime cover ________
The cephamycin drugs like cefotetan and cefoxitin have added ______ coverage
HNPEK (Haemophilus, Neiserria, proteus, E.coli klebsiella)
have added anaerobe coverage
3rd gen cephs are more resistant to _______ but have enhanced _______ coverage
resistant to streptococci
more gram - coverage
3rd gen ceph drug ceftazidime does not have any _____ coverage but is able to cover ________
no gram + coverage
is able to cover pseudomonas
3rd gen ceph + beta lactamase inhibitor combinations (ex: ceftazidime/avibactam and ceftolozane/tazobactam) are us able to cover what?
MDR pseudomonas
and more gram negative rods
what is the name of the 4th drug ceph?
cefepime
what is the only cephalosporin with MRSA coverage?
ceftaroline
Generally for the class of cephalosporins: they do not cover _______ or _________
enterobacteriacae or atypicals
What is oral cephalexin commonly used for?
MSSA skin infections
strep throat
What is oral Cefuroxime commonly used for?
otitis media
Community acquired pneumonia (CAP)
sinus infection
What is oral Cefdinir commonly used for?
Community acquired pneumonia (CAP)
sinus infection
What is IV cefazolin commonly used for?
surgical prophylaxis
What is IV cefotetan/cefoxitin commonly used for?
anaerobe coverage - B. fragilis
thus good for surgical prophylaxis (COLORECTAL surgeries)
what cephalosporin can cause disulfiram like reactions with alcohol
the cephamycins – ex: cefotetan
what age population should not use ceftriaxone?
neonates (0 - 28 days)
What is IV ceftriaxone/cefotaxime commonly used for?
CAP
meningitis
spontaneous bacterial peritonitis
pyleonephritis
which cephalosporin does not need renal adjustment
ceftriaxone
Ceftazidime and Cefepime are able to cover _______ infections
pseudomonas
common 1st gen cephs?
cefazolin
cephalexin
common 2nd gen cephs?
cefuroxime
cefoTEtan
Cefotetan has a ______ that causes disulfiram reactions and ________
NMTT side chain
and hypoprothrombinemia (bleeding)
main side effects of cephalosporins?
GI upset
rash
seizures with accumulation
common 3rd gen cephs?
cefdinir
ceftriaxone
cefotaxime
______ is available in a chewable tablet
cefixime
what cephalosporin/beta lactamase inhibitor combo is used for some CRE (carbapenem reistnant enterobacteriacae)
ceftazidime/avibactam
brand name for cefdinir?
omnicef
brand name for cefazolin?
Ancef
Kefzol
brand name for cefotetan?
Cefotan
brand for ceftriaxone?
Rocephin
brand name for cefotaxime?
Claforan
brand name for ceftazidime/avibactam?
Avycaz
brand name for ceftolozane/tazobactam?
Zerbaxa
brand name for ceftaroline?
Teflaro
what is the 4th gen ceph
cefepime
what carbapenem is give with cilastatin? and why?
imipenem
to prevent the drugs degradation by renal tubular dehydropeptidase
what carbapenem does not cover pseudomonas?
ertapenem
T or F:
Carbapenems do NOT cover what?
Atypials MRSA VRE C.Diff stenotrophomonas
Ertapenem does not cover pseudomonas or what other bugs?
acinetobacter
enterococcus
common uses for carbapenems?
- polymicrobial infections (ex mod-severe diabetic foot infections)
- empiric therapy when resistant organisms are suspected
- resistant pseudomonas or acinetinobacter
Carbapenem Warnings:
Avoid use in patients with ______
And there is a risk of ______
w/ PCN allergy
risk of seizures
what increases the risk of seizures with carbapenems?
using higher doses
renal impairment
using imipenem/cilastatin
Carabepenems are all administered via _____
IV
Ertapenem must be diluted with _______ before adminsitration
normal saline
T or F:
Aztreonam is likely safe to use with PCN allergy
true — cross reactivity is very rare
Typical coverage of aztreonam:
covers mainly gram _____
it has NO coverage of gram _____
gram - (even pseudomonas)
NO gram + coverage
brand name for aztreonam?
Azactam
Aminoglycosides:
exhibit _____ dependent antibacterial activity
and have a ________ effect
concentration dependent
post antibiotic effect
what type of dosing is good for aminoglycosides so that you can can get a good peak but less toxicity
extended internal dosing
Aminoglycosides:
kill gram _______ fast
and can act synergistically with ________ for some bugs
gram -
w/ beta lactams
Aminoglycosides:
notable toxicities?
renal damage
hearing loss/tinnitus/balance problems = ototoxicity
T or F:
Aminoglycosides do not cover pseudomonas
false - they do!
If using an extended interval dosing nomogram — if it falls on the line, round (up or down)
up
What is an extended interval dosing nomogram for aminoglycosides used for/ how does it work?
after one dose - draw a random level
on the nomogram it will help you determine the interval dosing
what drugs are aminoglycosides?
gentamicin
tobramycin
amikacin
Streptomycin
Dosing Aminoglycosides:
if the patient is underweight — use _______ weight
actual body weight
Dosing Aminoglycosides:
if the patient is obese — use ________ weight
adjusted body weight
Dosing Aminoglycosides:
if the patient is not obese — use ________ weight
ideal body weight or actual body weight – look at hospitals protocol
Traditional Dosing for Gentamicin/Tobramycin?
1 - 2.5 mg/kg/DOSE
use lower doses if gram + infection
Traditional Dosing for Amikacin?
5 - 7.5 mg/kg/dose
in what conditions should you NOT use extended interval dosing for aminoglycosides?
burns
ESRD
pregnancy
ascites
Monitor what for aminoglycosides?
renal function
drug levels
Boxed warning for aminoglycosides?
Nephro / oto - toxic
neuromuscular blockade/respiratory paralysis
avoid use with other neuro/nephrotoxic drugs
what drugs are known as the respiratory quinonlones and why?
levofloxacin
moxifloxacin
they have enhanced coverage of s. pneumoniae
what quinolone covers MRSA?
delafloxacin
Ciprofloxacin and levofloxacin have enhanced gram ______ coverage
negative
T or F:
Quinolones are first line for MRSA infections
false — with resistance being high with quinolones - have to avoid quinlones
brand name for moxifloxacin?
Avelox
All but one quinolone needs renally adjustment – which one does not need renal adjustment
moxifloxacin does not need the adjustment
Boxed warnings of quinolones?
tendon inflammation/rupture
peripheral neuropathy
seizures
what patient age population should not use quinolones
children
Quinolone warnings?
QT prolongation
hepatoxicity
photosensitivity
hypo and hyper glycemia problems
Cipro oral suspension should not be given via ______ and why?
and what to do instead?
do not give via NG tube or other feeding tubes
crush up IR cipro tablets in water and give via tube
which quinolone does not get into the urine enough/should not be used for UTIs?
moxifloxacin
which quinolones are good for pseudomonal infections?
cipro and levo
delafloxacin is mainly used for what type of infection?
skin infections - MRSA coverage
main drug interaction with the quinolones?
multivalent cations can chelate and inhibit absorption
what quinolones have a PO:IV ratio of 1:1
levofloxacin and moxifloxacin
Quinolone Tips:
- watch for additive toxicity of ________ with other meds
- avoid use in patients with _______
QT prolongation
w/ seizures
Quinolone Tips:
watch for tendon rupture (especially in _____ patients and patients using _____)
watch for neuropathy
older patients; and patients using steroids
Quinolone Counseling Tips:
- avoid ______ exposure
- separate from _______
- monitor ______
avoid sun exposure
separate from cations
monitor blood sugar - if DM
Macrolides:
have good _______ coverage
atypical
what drugs are macrolides?
azithromycin
clarithromycin
erythromycin
brand name for clarithromycin
Biaxin
Contraindication for Clarithromycin and Erythromycin?
contaminant use of lovastatin and simvastatin
ADEs of macrolides ?
GI upset (diarrhea, abdominal pain, cramping - especially erythromycin)
warnings of macrolides?
QT prolongation
hepatoxicity
which macrolide has the highest risk of QT prolongation?
erythromycin
T or F:
Azithromycin ER suspension is bioequivalent with Zithromax
false —-they are NOT interchangeable
which macrolides are 3A4 inhibitors?
erythromycin and clarithromycin
azithromycin - is a MINOR substrate - very few clinically significant drug interactions
With all macrolides do use other drugs that also ______
prolong the QT interval
Common uses for macrolides:
All can be used for ______ and as a beta lactam alternative for _______
used for CAP; alternative for strep throat
Azithromycin Uses:
- can be used for _________
- or as monotherapy for which STD?
- or combo therapy for which STD?
- prophylaxis for ______
- drug of choice for ________
used for COPD exacerbations mono: chlamydia combo: gonorrhea proph: MAC DOC for dysentery (travelers diarrhea with blood stools)
Doxycycline can be used for:
________ (mild infections)
and
even ______ in UTIs
CA-MRSA skin infections
VRE in UTIs
Tetracycline drug examples?
doxycycline
minocycline
Oracea 40 mg (a low dose of doxycycline) should be given how in relation to food?
on empty stomach (1 hr before food or 2 hours after)
Warnings of tetracyclines:
What groups of people should not use them?
Children under 8
pregnant
breastfeeding
(because of bone growth issues and permanently discolors teeth)
Warnings of tetracyclines:
can cause what two different kinds of skin issues?
DILE - drug induce lupus erythematosus (mainly minocycline)
and
photosensitivity
ADEs of tetracyclines?
N/V/D
IV: PO conversion for doxycyline and minocycline?
1:1
main drug interaction for tetracyclines?
divalent cations (Mg, Al, Ca)
iron containing preparations
sucralfate
bismuth salicylate
(separate 1 hr before; 2 hr after)
Doxycycline and minocycline commonly used for
________ infections and ______
CA-MRSA
and acne
Doxycycline is first line for ________ and _______ (tick borne diseases)
lyme disease
rocky mountain spotted fever
Doxycycline:
- or as monotherapy for which STD?
- or combo therapy for which STD?
mono: chlamydia
combo: gonorrhea
Tetracyline:
used in _______ treatment
H.pylori
Sulfamethoxazole/TMP:
dose is based on which component?
TMP componentn
Sulfamethoxazole/TMP dosing if uncomplicated UTI?
1 DS tab BID x 3 days
Contraindications of Sulfamethoxazole/TMP?
Sulfa allergy... and pregnant (at term)
ADEs of Sulfamethoxazole/TMP?
N/V/D Anorexia skin reactions crystalluria (thus take with water) photosensitivity increased K+ hypoglycemia decreased folate \+ coombs test
main drug interaction with sulfonamide abx?
they are inhibitors of 2C9 - aka interact with warfarin and can increase INR
common uses of Sulfamethoxazole/TMP?
CA-MRSA skin infections
UTI
PCP (pneumocystis pneumonia)
the Sulfamethoxazole/TMP ratio is always ___: ___
sulfa 5 : 1 TMP
ex: (400 / 80 )
common dosing for C. Diff for vancomycoin?
125 - 500 mg PO!! QID x 10 - 14 days
dosing for systemic infections for vanc?
15 - 20 mg/kg IV Q 8 - 12H
warnings for vancomyocin?
Neprhotoxicity and ototoxicity
Infusion/Red man syndrome
Vanc is 1st line treatment for ______ infections
MRSA infections
Monitor what when using vancomyocin
renal function
trough concentration
Goals for vanc trough?
15 - 20 for pneumonia, endocarditis, meningitis, osteo
10 - 15 for other infections
Consider a different drug than vancomyocin when MRSA MIC is > ___
2
examples of lipoglycopeptides
telavancin
oritavancin
dalbavancin
lipoglycopeptides have coverage similar to what other antibiotic
vancomyocin
which glycopeptides need to only be given once because of very long half lives?
oritavancin
dalbavancin
the lipoglycopeptides can falsely elevate ______
PT/INR
contraindication for oritavancin?
use of IV Unfractionated Heparin for 5 days after use because of interference of aPTT lab results
Side effects seen with lipoglycopeptides?
Red man syndrome
N/V
which lipoglycopeptide causes metallic taste
telavancin
infuse telavancin for how long to prevent red man syndrome?
OVER 60 minutes
boxed warnings for telavancin
- fetal risk
- nephrotoxicity
- increased mortality (vs vanc in some pts treated for pneumonia esp with renal impairment)
Daptomyocin Warnings:
can cause _______ and _______
and can falsely elevate ______
- myopathy and rhabdomyolysis
- elevate PT/INR
Daptomyocin Side effects and monitoring
increased CPK
check CPK levels weekly
Daptomyocin
is compatible with ______ but not _____
good with NS (not dextrose)
Do not use daptomyocin to treat what type of infection??
pneumonia (drug is inactivated in the lungs by surfactant)
what drugs are oxazolidinones?
linezolid
tedizolid
Contraindication for linezolid?
w/in 2 weeks of MAO inhibitor use
warning and side effects for linezolid?
duration related myleosuppression (thrombocytopenia)
can decrease platelets and cause HA/nausea/diarrhea
Counseling/administration point about linezolid suspension
DO NOT shake it!!
Use linezolid with caution what drugs?
serotonergic or adrenergic drugs
Synercid (quinapristin/dalfopristin) is not tolerated well and thus not used a lot – what kind of infections would it maybe be used?
for VRE infections (but NOT active against faecalis infections; just faecium)
Side effects of synercid?
arhralgias/myalgias (V COMMON) infusion reactions edema/pain phlebitis hyperbilirubinemia CPK elevations
Tigecycline: covers what bugs?
VRE, MRSA, gram negative, anaerobes and atypical
Tigecycline does not cover the 3 “___’s”
3 P’s = pseudomonas; proteus, providencia
Tigecycline:
T or F: Needs renal adjustment
FALSE
it does not need renal adjustment
Tigecycline:
Increased risk of _______
Side effects seen?
risk of death
N/V/D
Tigecycline
Avoid use in ______ infections
bloodstream
Tigecycline
When reconstitued it should be _________ - if it is not - throw it away
yellow/orange
Polymyxins: best as mono or combo therapy?
best as combo b/c of emerging resistance
Examples of polymyxin?
colistimethate or colistin
and polymyxin B….
main side effects warning with the polymyxins?
neuro (dizzy, HA, vertigo) and nephro toxic
you need to ASSESS THE DOSE carefully for colistimethate… why?
the dosing can be based off units of colistimethate sodium or mg of colistimethate sodium or mg of colistin base
what abx can cause Gray syndrome? (and what is gray syndrome)
chloramphenicol
gray syndrome = circulatory collapse/cyanosis
Chloramphenicol side effects
gray syndrome and myleosuppression
what abx needs a D test?
Clindamycin
(D test = test done if resistant to erythromycin but not clindamycin — may need to do this test to make sure that is correct)
boxed warning for Clindamycin?
C.diff
Rifaximin can it NOT be used for Spontaneous bacterial peritonitis or travelers diarrhea? and why?
SBP – it does not absorb well (stays in the gut!)
it CAN be used also for IBS with diarrhea, hepatic encephalopthy, refractory c.diff
