Dt, Kaplan Antibiotics

Front 1

bacterial cell wall synth. inhibitors (6)

Back 1

pencillins, cephalos, imipinem/meropenem, aztreonam, vanco

Front 2

bacterial protein synth. inhibitors (6)

Back 2

aminos, chloramphenicol, macrolides, tetras, streptogramins, linezolid

Front 3

nucleic synth. inhibitors (2)

Back 3

fluoroquinolones, rifampin

Front 4

folic acid synth. inhibitors (3)

Back 4

sulfonamides, trimethoprim, pyrimethamine

Front 5

moa penicillins/cephalosporins

Back 5

interact w/ penicillin binding proteins in cytoplasm and inhibit transpeptidation reactions that cause X-LINKING

Front 6

m.o. resistance for pens and cephalos?

Back 6

-beta lactamase production
- pbp change
- porin changes

Front 7

what bugs change their pbp structure?
what bug changes its porin channel?

Back 7

staph aureus, pneumococci
- pseudomonas

Front 8

spectrum of Pen-G / V?

Back 8

-narrow spectrum
- SENStive to Beta-lactamase
Pen-G = doc in syphilis
- strepto, pneumo,meningococci

Front 9

what is pen-V mainly used for?

Back 9

only oral admin
- streptococci
- oral pathogens and dental infections

Front 10

moa of "STAPHICILLIN?" (group of pens)

Back 10

nafcillin, methicillin, oxacillin
- good against STAPH (not mrsa)

Front 11

spectrum of aminopenicillins?

Back 11

-broader spectrum
- beta-lactam senstive
- g+ cocci (not staph)
- e.coli, h.flu, listeria, borellia, h.pylori

Front 12

which would u use ampicillin for?

Back 12

listeria

Front 13

what 2 specific bugs r reactive to amoxicillin?

Back 13

- borrelia burg
- h.pylori

Front 14

how is aminopenicillin activity enhanced?

Back 14

-use in COMBINATION w/ beta-lactamase inhibitors --> clavulanic acid , sulbactam

Front 15

clavulanic acid and sulbactam act as what for the penicillins?

Back 15

bodyguards by protecting them against bacterial derived b-lactamase

Front 16

how is ampicillin given?

Back 16

oral / iv

Front 17

aminopenicillins (ampicillin/amox) are synergistic with what other drug group against enterococci?

Back 17

synergistic w/ AMINOS

Front 18

these pencillins are the 4th variety of penicillins and are often called " antipseudomonal penicillins?"

Back 18

ticarcillin, piperacillin
- extended spectrum, antipseudomonal, b-lactamase sensitive

Front 19

ticarcillin/piperacillin activity against?

Back 19

enhanced activity against G- RODS (pseudomonas)
- enhanced if used w/ b-lactamase inhibitors
- synergistic w/ aminos against pseudomonas

Front 20

majority of pens are eliminated how?

Back 20

renal elimination
- short half life of less than an hour
- dose reduction need in Rnl dysfunction

Front 21

these 2 pens largely eliminated in bile

Back 21

- nafcillin
- oxacillin

Front 22

pen that undergoes enterohepatic cycling, but eventually excreted by kidney

Back 22

ampicillin ; most likely to cause GI trouble

Front 23

main side fx associated w/ pens?

Back 23

hypersensitivities
- urticarial skin rash common
- anaphylaxis is possible

Front 24

interstitial nephritis is seen w/ which pen?

Back 24

methicillin

Front 25

cephalosporins...moa?

Back 25

same as pens--> interact w/ cytoplasmic PBP'S and inhibit transpeptidation reactions, thereby inhibiting cell wall synth

Front 26

m.o. of resistance to cephalos?

Back 26

- b-lactam production
- pbp change
- porin change

Front 27

name the 2 main 1st generation cephalosporin drugs

Back 27

-cefazolin
- cephalexin

Front 28

spectrum of generation 1 cephs?

Back 28

g+ cocci (not mrsa)
- e.coli, klebs and proteus
--> P.E.K. + G(+) bugs

Front 29

main use for first gen cephs?

Back 29

surgical prophylaxis b/c main infections in surgical wounds r caused by --> g+ strep/staph y g(-) e.coli

Front 30

cns entry of 1st gen cephalos?

Back 30

no cns entry

Front 31

name 3, 2nd gen. ceph drugs

Back 31

-cefotetan
-cefaclor
-cefuroxime

Front 32

spectrum of 2nd gen?

Back 32

increased g- coverage y partial anaerobic coverage

Front 33

name of the only 2nd gen cephlo to enter cns?

Back 33

cefuroxime

Front 34

mnemonic for coverage of 2nd gen cephalos?

Back 34

H-PEK

Front 35

name 4, 3rd gen cephalos?

Back 35

-ceftriaxone (im)
- cefotaxime (parenteral)
- cefdinir (oral)
- cefixime (oral)

Front 36

spectrum of 3rd gen cephalos?

Back 36

G+/G- COCCI
- many G- rods

Front 37

cns entry?

Back 37

all enter cns

Front 38

what are 3rd gen cephs important for? (ceftriaxone, cefotaxime, cefdinir, cefixime)

Back 38

- empiric rx of mengitis and sepsis

Front 39

name the 1, 4th generation cephalosporin?

Back 39

- cefepime (IV)
- not used much b/c held in reserve as a backup in case others fail

Front 40

spectrum of cefepime IV?

Back 40

wider spectrum
- resistant to most b-lactamases
- CNS entry :)

Front 41

active tubular secretion of cephalos, and drug half lives are increased by using what drug in the kidney?

Back 41

- probenicid prevents active tubular secretion of cephalos

Front 42

which 2 drugs r eliminated in the BILE?

Back 42

cefoperzone
- CEFTRIAXONE (largely eliminated in bile)

Front 43

side fx of cephalos?

Back 43

- hypersensitivities (2%)
- rashes most common
- assume x-allergenicity if allergic to pens

Front 44

if patients are allergic to pen's and cephalos, which drugs can they consider?

Back 44

G+ bug --> macrolides
G- bug --> aztreonam

Front 45

which 3 antibiotics of cephalos do u want to AVOID drinking alcohol, due to the disulfiram fx?

Back 45

- cefotetan
-cefoperazone
- cefamandole
*All 3 inhibit alcohol dehydrogenase and cause a build up acetaldehyde in the blood/body

Front 46

These bugs make Cephalosporins, LAME!

Back 46

LAME
L- listeria
A- atypicals (chalmydia/myco)
M- MRSA
E- enteroCOCCI

Front 47

Imipinem and Meropenem moa?

Back 47

same as pens
- gi distress
- imipenem = seizures w/ renal dysfunction

Front 48

where are imipenem and meropenem used?

Back 48

mainly used in hospitals b/c only given via IV
- empiric use for life threatening infections

Front 49

imipenem / meropenem spectrum of action?

Back 49

gram (+) cocci, gram (-) rods (enterobacter / pseudomonas) + anaerobes

Front 50

imipinem is given w/ which drug to inhibit its metabolism?

Back 50

imipenem is given with CILASTATIN to decrease its metabolism via RENAL DYHYDROPEPTIDASE

Front 51

moa of Aztreonam?

Back 51

-same as pens
- resistant to b-lactamases

Front 52

uses of aztreonam?

Back 52

- mainly GRAM (-) RODS IV

Front 53

is Aztreonam x-allergenic with pens / cephs?

Back 53

there is no x-allergenicity w/ aztreonam

Front 54

moa of Vancomycin?

Back 54

binds @ d-ala+d-ala muramyl pentapeptide and sterically hinders the transglycosylation reactions that are involved in the elongation of the peptidoglycan chains
- DO NOT INTERFERE W/ PBP's

Front 55

vancomycin spectrum?

Back 55

MRSA
Enterococci g+
c.dif (backup drug)

Front 56

resistance to vanco occurs via?

Back 56

change in muramyl peptide target; d-ala changes to d-lactate (terminal one)

Front 57

in colitis how is vanco used? does it penetrate the cns?

Back 57

IV b/c of low absorption in that condition
- no cns penetration
- penetrates tissues well, and can penetrate bone --> osteomyelitis use

Front 58

elimination of vanco? length of half life?

Back 58

- renally eliminated
- long half life

Front 59

main side fx of vanco?

Back 59

-red man syndrome due to histamine release (decrease rate of iv admin to lower red manism)
- permanent ototoxicity
- nephrotoxic

Front 60

2 drug classes that bind to 30S

Back 60

- tetras
- aminos

Front 61

7 drug classes that bind to the 50S ribosome?

Back 61

-linezolid
- dalfo/quinupristin
- chloramphenicol
- macrolides
- clindamycin

Front 62

these drugs prevent the formation of the initiation complex...

Back 62

aminoglycosides (30s)
linezolid (50s)

Front 63

aminos cause what to happen to the protein synth?

Back 63

aminos cause misreading of the genetic code and thus prevent proper protein formation...also incorporation of wrong amino acids in the chain --> CIDAL fx

Front 64

this drug inhibits the activity of the bacterial peptidyl transferase?

Back 64

chloramphenicol

Front 65

these drugs prevent / block the attachment of aminoacyl TRNA to the acceptor site ...?

Back 65

tetras (30s)
- dalfo/quinupristin (50s)

Front 66

these drugs work on the 50S subunit; inhibit the translocation of PEPTIDYL TRNA from the ACCEPTOR to the DONOR site (static)

Back 66

macrolides and clindamycin

Front 67

y do aminos only work on aerobic bugs?

Back 67

aminos need O2 to enter the cell of the bacteria b/c the uptake mechanism in the bacteria uses o2
--> thus causing an intrinsic resistance of ANAEROBIC bacteria

Front 68

spectrum of aminos?

Back 68

G- rods

Front 69

3 main aminos ?

Back 69

GENTAMYCIN , TOBRAMYCIN, amikacin
- used in combo

Front 70

aminos + penG / ampicillin for which bugs?

Back 70

enterococci

Front 71

Aminos + extended spectrum penicillin or 3rd gen ceph (ceftriaxone,cefdinir, cefotaxime, cefixime) for which bug?

Back 71

pseudomonas aeruginosa

Front 72

streptomycin is used in which bugs?

Back 72

TB
- doc --> bubonic plague and tularemia

Front 73

y is neomycin only used topically?

Back 73

b/c its too toxic systemically

Front 74

what main aminoglycoside is used to treat gonorrhea?

Back 74

SPECTINOMYCIN

Front 75

y are aminos not absorbed orally or widely distributed into the tissues?

Back 75

b/c aminos are POLAR COMPOUNDS

Front 76

RENAl elimination is proprotional to what?

Back 76

renal elimination of aminos is proportional to GFR
- need major dose reduction in renal dysfunctional states

Front 77

what is the only class of abx that can be administered with ONCE DAILY DOSING?

Back 77

AMINOS
- fx depend on peak drug level, and it has POST-ANTIBIOTIC FX --> bug killing continues long after it reaches below toxic levels in the blood
- "hit and run" fx

Front 78

main side fx of aminos?

Back 78

nephrotoxicity , acute tubular necrosis that is reversible
- potentiated via use of --> vanco, ampB, cisplat and cyclosporin

Front 79

this side fx of aminos occurs roughly 2% of the time

Back 79

ototoxicity , aminos are toxic to the hair cells in the ear
- irreversible deafness
- reversible vestibular dysfunction
- toxicity enhnaced by LOOP use

Front 80

side fx of neomycin?

Back 80

contact dermatitis

Front 81

moa of tetras ?

Back 81

bind to 30S subunit
- block association of aminoacyl trna to the acceptor site

Front 82

spectrum of tetras?

Back 82

broad spectrum
- good chlamydia/mycoplasma activity
- h.pylori
- rickets, borrelia, brucella and vibrio

Front 83

what conditions are tetras used prophylactically for?

Back 83

- acne
- chronic bronchitis in winter time for susceptible age groups

Front 84

tetras are the doc for which bugs?

Back 84

lyme disease
- cholera

Front 85

name the 3 main drugs for class of tetracyclines?

Back 85

- doxycycline
- minocycline
- demeclocycline

Front 86

which 3 classes of drugs cause phototoxicity?

Back 86

- tetras
- sulfonamides
- quinolones

Front 87

tetras are the backup drug for which bug?

Back 87

syphilis
- backup drug to pen-G

Front 88

this drug is better than tetracycline hcl and can b used in prostatitis

Back 88

-doxycycline
- reaches high levels in the prostatic fluid
- metabolized in the liver

Front 89

this drug has high levels in the saliva and tears, and often used as prophylaxis for a patient who has the meningococcal carrier state?

Back 89

minocycline

Front 90

this tetracycline is used in the rx of SIADH due to its blockage of the ADH receptor in the collecting ducts?

Back 90

demeclocycline

Front 91

majority of tetras are eliminated how?

Back 91

renally

Front 92

doxy is eliminated through which organ?

Back 92

liver

Front 93

y cant u use chelators when giving tetras?

Back 93

tetras bind to DIVALENT CATIONS (ca2+, Mg2+, Fe2+) --> causes decreased absorption
- also cannot use antacids during tetra rx

Front 94

this drug is similar to tetras, is not affected by efflux pumps of bacteria, is a broad spectrum drug and is indicated for VANCOMYCIN RESISTANT organisms?

Back 94

Tigecycline

Front 95

y cant we use tetras in children?

Back 95

- tetras decreases bone growth in kids
- tooth enamel dysplasia --> teeth turn gray/brown

Front 96

these 2 tetras cause phototoxicity?

Back 96

demeclo, doxy

Front 97

these drugs can cause n,v,d and superinfections leading to which conditions in the upper and lower gi tracts?

Back 97

- upper gi --> candidiasis superinfection
- lower gi --> staph aureus colitis

Front 98

this tetra can rarely cause dizziness

Back 98

minocycline

Front 99

at high doses tetras cause what?

Back 99

liver dysfunction in pregnancy
CONTRAINDICATED IN PREGNANT WOMEN

Front 100

what is the clinical triad for Fanconi syndrome?

Back 100

polyuria
polydypsia
low back pain
- caused by outdated tetras

Front 101

chloramphenicol? moa?

Back 101

works on the 50S ribosomal subunit... inhibits the activity of peptidyltransferase
- bacterioSTATIC
- basically prevents the making of a new peptide bond

Front 102

is chloramphenicol a doc for any diseases?

Back 102

nope

Front 103

this drug is a backup drug for salmonella, b.fragile, rickettsia

Back 103

chloramphenicol

Front 104

tissue distribution of chloramph?

Back 104

good, csf penetrance as well

Front 105

how is chloramphenicol metabolized?

Back 105

hepatic glucoronidation ; need dose reductions for liver dysfunction in neonates

Front 106

how is gray baby caused?

Back 106

neonates dont have enough glucoronosyl transferase

Front 107

does chloramphenicol induce or inhbiit p450?

Back 107

chloramphenicol INHIBITS P450

Front 108

side fx of chloramp?

Back 108

- dose dependent bone marrow suppression
- aplastic anemia (1/35k)
- gray baby syndrome

Front 109

moa of macrolides?

Back 109

inhibition of TRANSLOCATION of PEPTIDYl tRNA from acceptor site to the donor site
- 50S

Front 110

3 examples of macrolides

Back 110

erythromycin, azithromycin, clarithromycin

Front 111

erythromycin is commonly used for ?

Back 111

middle ear infections --> m.cat / H.flu
- strep/staph
- atypical bugs (chlam,mycoplsma, ureaplasma)
- legionella
- camp.jejuni

Front 112

what type of pneumonia is macrolides a common use for?

Back 112

community acquired pneumonia
- m.pneumoniae
- c.pneumoniae
- no action against viruses (other common cause of community acquired pneumonia)

Front 113

what 2 macrolides are metabolized by liver and excreted in the poo? (bile)
- p450 fx?

Back 113

erytho/clarithromycin
- INHIBIT P450

Front 114

are erythro/clarithro safe in pregnancy?

Back 114

NOOOO

Front 115

how is azithromycin better than erythro/clarithromycin?

Back 115

- azithro is renally eliminated
- NO p450 actions
- SAFE IN KIDS AND PREGNANT WOMEN

Front 116

what abx stimulate the motilin receptors and commonly cause g.i. distress?

Back 116

macrolides
- erythro/azithro > clarithro

Front 117

at high doses, what do macrolides do?

Back 117

cause reversible deafness @ high doses

Front 118

what drug works on macrolide resistant bacteria?

Back 118

Telithromycin

Front 119

what form of erythromycin is quickly absorbed, and causes cholestasis / jaundice in pregnancy and in the elderly?

Back 119

erithromycin estolate
- elderly > 60 yoa

Front 120

What type of drug is Clindamycin?

Back 120

clindamycin is a LINCOSAMIDE
- inhibits translocation peptidyl tRNA from acceptor to the donor site on the 50S ribosomal subunit of the freaking bug

Front 121

spectrum for clindamycin?

Back 121

narrowwwww
- g+ cocci and anaerobes
- backup drug to b.fragilis
- can b used in toxo

Front 122

this drug is the first known abx to cause what g.i. disease?

Back 122

pseudomembranous colitis

Front 123

why does clindamycin work in osteomyelitis ?

Back 123

clinda has good bone penetration
- good for G+ cocci

Front 124

name the 6 abx drugs that u dont want to use in a pregnant woman?

Back 124

1.) aminos
2.) erythromycin estolate
3.) clarithromycin
4.) fluoroquinolones
5.) sulfonamides
6.) tetras

Front 125

THIS drug prevents the formation of the initation complex in bacteria via the PREVENTION of N-FORMYLMETHIONYL- tRNA- ribosome -mRNA ternary complex?

Back 125

Linezolid prevents the formation of the ternary complex :)

Front 126

spectrum of action of linezolid?

Back 126

used in VRSA, VRE and drug-RESISTANT Pneumococci
- basically, its used in bugs that are vancomycin resistant :(

Front 127

side fx of linezolid?

Back 127

bone marrow suppression
- observe via a depression in platelet levels

Front 128

These 2 drugs act via --> a.) binds to 50 S ribosomal subunit and trna acceptor site and stimulates its dissociation from the ternary complex --> b.) dcreses the release of the completed polypeptide via blockage of its extrusion?

Back 128

Quinupristin / Dalfopristin

Front 129

spectrum of dalfo/quinupristin?

Back 129

used PARENTERALLY in SEVERE infections caused -->
VRSA, VRE and other G+ cocci

Front 130

what is... a substance that inhibits cell growth via competition or substitution of a natural substrate in an enzymatic process?

Back 130

antimetabolite

Front 131

these 2 abx classes act as antimetabolites as their moa?

Back 131

- sulfonamides
- trimethoprim

Front 132

inhibitors of folic acid synthesis are also by association inhibitors of what ?

Back 132

nucleic acid synthesis

Front 133

3 examples of folic acid synth. inhibitors?

Back 133

- sulfonamides
- trimethoprim
- pyrimethamine

Front 134

folic acid synth is via..

Back 134

pteridine + PABA --> (dihydropterate synthetase) --> dihydropteric acid + glutamate --> dihydrofolic acid --> (dihydrofolate reductase) --> tetrahydrofolic acid (active folate form)

Front 135

these drugs inhibit DIHYDROPTERATE SYNTHETASE

Back 135

- sulfonamides

Front 136

these drugs inhibit DIHYDROFOLATE REDUCTASE

Back 136

- trimethoprim and pyrimethamine (works in toxo)

Front 137

why do these drugs work?

Back 137

b/c some bugs have to synthesize their own folic acid in order to survive...we dont have to, we get ours from our good vegetarian diet :)

Front 138

this drug is a prodrug of salicylate and is used in what 2 conditions?

Back 138

-ulcerative colitis
- rheumatoid arthritis

Front 139

Ag Sulfadiazine is used when?

Back 139

burn patients

Front 140

combination of trimethoprim- sulfamethoxazole is used bc?

Back 140

inhibition of both dihydropterate synthetase and dihydrofolate reductase --> makes it much harder for a bacteria to confer resistance to abx when getting hit from 2 directions... BYAAHHHH!!!

Front 141

combination of trimethoprim/sulfamethoxazole is called what?

Back 141

sequential blockade of folate synthesis

Front 142

tmp/smx is co-doc for which infections?

Back 142

- utis
- resp/ear/sinus infections
- h.flu/m.cat
- mrsa/vibrios (DOC)
- pcp pneumonia

Front 143

tmp smx is doc for which bacteria?

Back 143

NOCARDIA

Front 144

TMP /smx is good for which other bugs?

Back 144

- nocardia
- mycobacteria
- g (-) bugs --> (e.coli, salmona,shig,h.flu --> common causes of uti's)
- g(+) bugs --> staph,strep

Front 145

which fungi and protozoans are tmp/smx good for?

Back 145

- fungus --> pcp
- protozoa --> toxo (sulfadiazine + pyrimehtamine)

Front 146

sulfonamdies conjuated how?

Back 146

- hepatically acetylated
- renally excreted (drink lots of water batch!) otherwise u get CRYSTALLURIA

Front 147

how do sulfonamides cause d-d interactions?

Back 147

sulfas bind to albumin, which displaces other drugs and increases their activity in the body

Front 148

what common drugs can be displaced by sulfonamides?

Back 148

methotrexate
- phenytoin
warfarin

Front 149

what trimester do you avoid sulfonamides ?

Back 149

sulfas x-the placental barrier
- 3rd trimester
- can cause kernicterus in neonates
- hard to metabolize bilirubin and bilirubin deposits in the brain causing irreversible brain damage

Front 150

sidefx of sulfonamides?

Back 150

2nd to pens in causing hypersensitivity rxns
- phototoxicity
- stephen johnson syndrome

Front 151

trimethoprim/ pyrimethamine side fx to the bone?

Back 151

bone marrow suppression due to decreased folic acid production
- enterocolitis

Front 152

this class of abx are direct inhibitors of nucleic acid synth?

Back 152

quinolones!

Front 153

name 3 drugs of quinolone family

Back 153

- norfloxacin
- ciprofloxacin
- ofloxacin
--oxacins

Front 154

quinolones can also be used to treat this bug, which can also be treated with pens and tetras ?

Back 154

anthrax

Front 155

moa of fluoros?

Back 155

inhibits topo2 and topo 4

Front 156

resistance is building to fluoros b/c of what?

Back 156

G(+) cocci --> via topo4 --> MRSA
G(-) rods --> topo 2

Front 157

narrow or wide spectrum of action of flouros?

Back 157

WIDE SPECTRUm
- utis
- stds, pid's

Front 158

fluoro used for chlamydia?

Back 158

ofloxacin

Front 159

fluoro used for gonorrhea?

Back 159

cipro/ ofloxacin

Front 160

fluoros can also be used in skin, tissue infections as well as where else?

Back 160

-bone infections --> used in OSTEOMYELITIS

Front 161

any quinolone can be used for diarrhea caused by ?

Back 161

shigella
salmonella
e.coli
campy. jejuni

Front 162

levofloxacin is used for?

Back 162

drug resistant pneumococci

Front 163

active secretion of fluoros in the kidney can be inhibited by which medication?

Back 163

probenicid

Front 164

why cant u drink milk when taking fluoros?

Back 164

iron and calcium inhibit absorption

Front 165

what are the 4 main side fx of fluoros?

Back 165

-tendonitis rupture in young adults
- QT INTERVAL PROLONGATION
- CONTRAINDICATED IN PREGNANCY :)
- no use in children due to disruption of chondrogenesis in the epiphyseal plates

Front 166

these are the antibiotics for h.pylori in g.i. ulcers? BMT REGIMEN

Back 166

BMT regimen
B = bismuth
M= metronidazole
T= tetracycline
or --> clarithro/amox/omeprazole

Front 167

moa of METRONIDAZOLE?

Back 167

unknown...
produces FREE RADICALS and is BACTERICIDAL

Front 168

METRO is the DOC for which condition caused by overuse of antibiotics?

Back 168

pseudomembranous colitis

Front 169

Metro is DOC for these 3 PROTOZOANS!

Back 169

GET!
G= giardia
E= entamoeba
T= trichomonas

Front 170

metro is used for the majority of Gram (-) bacteroides and which other species?

Back 170

Clostridium

Front 171

metro is also used in what 2 other infections?

Back 171

- g.vaginalis (overactive vagina)
- h.pylori (stomach ulcers)

Front 172

side fx of metronidazole... do u take it while drinking alcohol? do u like the taste of metal?

Back 172

- stomatitis, metallic taste, cystitis, glossitis
- n,drrha
-dont drink w/ alcohol due to its disulfiram fx
- reversible p.neuropathy

Front 173

What Rx regiment is used for Tb?

Back 173

STRIPE therapy
St= streptomycin
R= rifampin
I= isoniazid
P= pyrazinamide
E= ethambutol

Front 174

what drug is used prophylactically for tb?

Back 174

isoniazid...but rifampin if patient is intolerant

Front 175

moa of isoniazid?

Back 175

inhibits mycolic acid synthesis
- must be converted by catalase to active form

Front 176

how does high level resistance form in the use of Isoniazid?

Back 176

high level resistance --> deletions in the katG GENE
- encodes catalase needed for bioactivation in the bacteria

Front 177

Low level resistance in INH rx?

Back 177

inhA gene deletions --> encodes the acyl protein in the mycolic acid target

Front 178

side fx of INH?

Back 178

-hepatitis (depends on age)
-peripheral neuritis (use b6 to prvnt)
- sideroblastic anemia (b6 to prevent)
-hemolysis in g6pd
- sle in slow acetylators

Front 179

Rifabutin is the preferred form of rifampin...but how does it work?

Back 179

rifampin inhibits dna-dependnt rna polymerase --> inhibits nucleic acid synth

Front 180

side fx of rifampin?

Back 180

- syndrome of flu-like symptoms that really isnt the flu
- p450 INDUCTION
- RED/ORANGE PEE

Front 181

moa of EthambutoL?

Back 181

- inhibits ARABINGALACTAN synthesis

Front 182

side fx of ethambutol?

Back 182

retrobulbar neuritis
- dcrsed visual acuity
- red/green color discrimination changes

Front 183

moa of pyrazinamide?

Back 183

not known
- activated by bacteria
- strains that are resistant lack the bioactivating enzyme

Front 184

sidefx of pyrazinamide?

Back 184

- polyarthralgia
- hepatitis
- hyperuricemia --> increases risk of gout
- phototoxicity
- increased porphyrin synth

Front 185

what condition would pyrazinamide be contraindicated in?

Back 185

porphyrias

Front 186

rx for MAC?

Back 186

prophylaxis --> azithromycin once a week or clarithromycin daily
rx --> clarithromycin + ethambutol +/- rifabutin