antimicrobial therapy

Question 1

pathogens

Answer 1

sterile fluids are CNS, urine, and blood

Question 2

classes of abx

Answer 2

cell wall active agents: -bela lactase ( PCN, cephalosporins), Aztreonam, Vancomycin, carbapenems

protein synthesis inhibitors:
macrocodes, clinda, tetracyclines, linezolie

interfere with DNA synthesis: fluroquinolones, rifamycin

Question 3

PCN class

Answer 3

MOA: Beta lactam-binds to PCN -binding protein to inhibit cell wall synthesis

spectrum: gram positive gram negative

AE: hypersensitivity, GI, hematologic, lowers seizure threshold

DI: OCs

PCN G- IM, IV

PCN VK:PO- best on empty stomach

antistaph PCN-staph and and fair streptococcal activity

amino PCN: ampicillin amoxicillin
- spectrum: enterococci, listeria, H. pylori

Extended spectrum- zosyn, mezlocillin, azlocillin
- spectrum: anti-pseduomasal coverage
indications: serious infections
Inpatient tx

Question 4

beta lactate inhibitors

Answer 4

• combined with PCN
  sublactam, clavuulanic
• activity for wide range of infections, respiratory tract, animal bits, skin infections

SE: diarrhea

Question 5

cephalosporins

Answer 5

spectrum: broader are cephalosporin progresses
Gram + –> gram + and gram -
No Enterococcus spp or listeria

eliminated via renal
don’t adjust cefriaxone

MOA: inhibit cell wall synthesis

SE: allergic rnn, cross reactivity with PCN

Question 6

first gen cephalosporins

Answer 6

Reflex, Ancef

skin infections, strep, prepop prophylaxis

Question 7

second generate

Answer 7

ceclor, cefprozil, caftan

• increases risk for bleeding
• avoid ETOH
• more gram negative, less gram positive

indication: URI, UTI, skin infection

Question 8

third generation

Answer 8

ceftriaxone

• excellent CNS penetration
• use for meningitis
• ceftaz has pseudomas activity

Drug of choice: gonorrhea

Question 9

fourth/fifth generation

Answer 9

cefepime- gram postive and gram negative

Teflaro- IV
-gram pos, gram neg, MRSA , and resistant to S. pneumonie

Question 10

Aztreonam

Answer 10

use for pt who has anaphylactic rx to PCN

cover gram negative including pseudomonas

renally cleared

Question 11

carbapenems

Answer 11

broadest class of abx

excellent for gram negative and gram positive
No MRSA, MRE
NO pseudomonas-ertapenems

indications: lower respiratory infections, intra-abdominal infections, bacterial sepsis
UTI
skin/skin structures, endocarditis

meropenem- CNS -related infections
ertapenem- Invanz IM

renal elimination

precipitates seizure activity

cross sensitivity with PCN

Question 12

fluroquinolones

Answer 12

cipro, levaquin

MOA: bind and inhibitor DNA synthesis

good tissue penetration
good gram positive
gram negative( cipro)

indications: URI, skin infections, anthrax, traveler’s diarrhea

AE: GI, CNS, cartilage toxicity ( no pets), tendon rupture, photosensitivity, QT prolongation( cipro least), rash, worsens MG

check drug interactions: warfarin, theophylline, drugs affecting blood glucose,

always separate calcium intake with abx

Question 13

macrolides

Answer 13

erythromycin, clarithromycin, azithromycing

MOA: inhibits protein synthesis

• gram postive, some gram negative and atypical
  indications: resp infections lyme, GI ulcers, MAC chlamydia, skin infections

AE: GI, ototoxicity, prolong QT, tate changes

DI: inhibit cytochrome P450

Question 14

ketolides

Answer 14

ketek-telithromycin

MOA: protein synthesis inhibitor

spectrum: gram postive,gram negative,

AE: hepatic dysfunction( not used in pads), CI with MG
DI: inhibitor CYP 3A4

Question 15

tetracyclines

Answer 15

cover H.pylori, spirochetes, community acquire MRSA

tetracycline, doxycycline ,minocycline

indications: acne, resp tract, lyme, ricettsia

AE: photosensitivity, deposition in teeth and bones ( dont use in peds and preggers)
DI: chelation with calcium supplements, OC, warfarin

Question 16

glycycyclines

Answer 16

tygvacil
gram positive and gram negative but no pseudomonas

indications: second line agent for CAP or intra-abdominal infections

AE: n/v

Question 17

ahminoglycosides

Answer 17

gentamicin, tobramycin
IV only

indications: generally gram negative and infections in hospital

AE: neprotoxicty, ototoxic, neuromuscular blockade

Question 18

sulfonamides

Answer 18

Bacterium

DOC: UTI, PCP
CAP

AE: GI, hypersensitivity, bone marrow suppression, photosensitivity

DI: OC, warfarin, sulfonylureas

Question 19

metronidazole ( flagyl and Tindzdazole

Answer 19

trichimonas
c.diff

AE: metallic tate, urine changes

DI: ETOH, warfarin

Question 20

clindamycin

Answer 20

gram postive and anerobic
Community-acquired MRSA
PCN allergic pt

AE: GI, c.diff

Question 21

fidaxomicin ( difcid)

Answer 21

recurrent C.diff

Question 22

Rifampin

Answer 22

TB, meningicoccal

AD: organs-red body fluids, hepatotoxicity, GI, flu-like sxs

Question 23

MRSA abx

Answer 23

vance, zyvox

Question 24

vancomycin

Answer 24

IV- MRSA
oral - used for C.diff

AE: red man syndrome, thrombophlebitis, nephrotoxicity, toxicity

check trough -10- 20 mg/L , if not then they get resistant

Question 25

zyvox -linezolid

Answer 25

oral/ IV
used for pneumonia
AE: myelosuppression until 2 weeks of tx,
inhibits MAO, SSRI

Question 26

UTI managetment

Answer 26

macrobid- avoid if they have renal issues

bactrim

Question 27

anti-vitals

Answer 27

acyclovir, famvir, valtrex

• goal is to tx first episodes

herpes zoster- varicella( speeds healing, dec. pain/ neuralgia)

severe infection: –> acyclovir

AI: GI headache

Question 28

influenza tx

Answer 28

relenza and tamiflu- cover flu a and b

Amantadine and rimantadine- influenza A and prevention
AE: GI, CNS

Question 29

CMV

Answer 29

gancilovir, fosacir, visited

manage counts

Question 30

hep b management

Answer 30

interferon alpha
entecavir

goal: dec. hep b levels
and improve liver histories

Interferon ( SQ)
4mon-1 year
flu-like scans
bone marrow suppressions
psych symptoms

Question 31

hep c tx

Answer 31

peg interferon and ribavarin

SE: ribavarin- hemolytic anemia, tetragenic
neutropenia

Question 32

anti fungals

Answer 32

azoles, polyenes ( ampotericin- covers everything)
lamisil- use for dermatophyte infections

AE: ampho- nephrotoxit

azoles- hepatic, QT prolongation

terbinafine- liver enzymes

drugs interactions are common
ketokonzaole/ itraconazole- check on h2 blockers, needs acidic environment

rifampin- increased cleared for azoles

Question 33

bug and drugs

Answer 33

MSSA
MRSA- vance

community -acquired MRSA- clinda, bacterium
complicated: vanc, dap

strep pyogenies: PCN V or G,
for PCN-allergic: clinda or macrolide

strep pneumo: PCN V or G or amox

moraxella ca- caftan
nester gone- ceftrizxone
n. meningi- pCN g
c.diff- metronidazole, recurrent vanco oral

e.coli/kelb- cefrixone

proteus mirablis- ampicillin

h. flu- URI: bacterium
h. pylori: PPI+ clarithro+ amor or flagyl

chlaymdia- macrolide
mycoplasma pneumonia: macrolides

Question 34

drug interactions

Answer 34

macrocodes- inhibit cytochorne p50
rifampin- induces Cp50
fluroquin and tetracyclines- chelated by divalent cations
linezolid- MOA
ETOH- flagyl, cefotetan
oral contraceptives -amox, PCN

photosensitivity: bacterium, tetracycline

Rash: fluroquin

QT prolongation: fluroquinolones, macrolides,

Red man syndrome- vanco, slow down infusion

Nephrotoxic/ ototoxic: vanco and aminoglycodies

seizures: PCN, fluroqin

Mono: amor

bone marrow suppression: bacteria, linezolie
GI: multiple drugs ( clauvante)

taste: clarithromycin, metronidazole
tendonitis: fluroquinolodes

orange/red-rifampin

CI with peds: tetra, fluroquinolones, telithromycin, bacterium

Question 35

anti fungal efficacy

Answer 35

gold standard: amphotericin B( renal issues)

aspergillosis: voriconazole, amphotericin

blastomycosis: itraconazole
amphoterecin, fluconazole

candidemia: fluconazole, amphotereicin, voriconazole
coccidiomycosis: itraconazole, fluconazole