MSK/CT

Question 1

what do LTC4, LTD4, LTE4 do?

Answer 1

leukotrienes

affect bronchial tone

Question 2

what does LTB4 do?

Answer 2

leukotriene

increases neutrophil chemotaxis

Question 3

what does PGI2 do?

Answer 3

prostaglandin

decreases platelet agg and vascular tone

Question 4

what does PGE1 do?

Answer 4

prostaglandin

decreases vascular tone

Question 5

what do PGE2 and PGF2 do?

Answer 5

increase uterine tone

Question 6

what does TXA2 do?

Answer 6

increases platelet aggregation and vascular tone

Question 7

what step of inflammatory cascade is blocked by corticosteroids?

Answer 7

phospholipase A2: production of arachidonic acid

Question 8

what step of inflammatory cascade is blocked by zileuton?

Answer 8

lipoxygenase: blocks leukotriene production

Question 9

what step of inflammatory cascade is blocked by montelukast, zafirlukast?

Answer 9

LTC4/LTD4/LTE4 receptor antagonists

block increase in bronchial tone

Question 10

what step of inflammatory cascade is blocked by aspirin, NSAIDs?

Answer 10

COX1/COX2

blocks AA –> cyclic endoperoxide (precursor to PGs and TXA2)

Question 11

acetaminophen MOA?

Answer 11

reversibly inhibits COX, mostly in CNS

inactivated peripherally

Question 12

how does acetaminophen cause hepatic necrosis?

Answer 12

metabolite NAPQI depletes glutathione and forms toxic tissue byproducts in liver

** NAC regenerates glutathione

Question 13

aspirin MOA?

Answer 13

IRREVERSIBLE inhib of COX1/2 by ACETYLATION
increases bleeding time
PT/PTT unaffected

** low dose –> platelets. medium dose –> antipyretic/analgesic. high dose –> anti-inflammatory

Question 14

aspirin toxicity?

Answer 14

gastric ulceration
tinnitus
chronic –> ARF, interstitial nephritis, GI bleeds

• • Reyes - in children with viral infx
• • respiratory alkalosis –> mixed met acidosis and resp alkalosis

Question 15

celecoxib?

Answer 15

COX2 inhibitor
spares platelet function

toxicity: increased thrombosis risk. sulfa allergies.

Question 16

NSAID toxicity?

Answer 16

interstitial nephritis
gastric ulcer
renal ischemia

Question 17

bisphosphonate MOA?

Answer 17

pyrophosphate analog

bind hydroxyapatite in bone –> OC activity inhibition

Question 18

bisphosphonate toxicity?

Answer 18

corrosive esophagitis - sit up after taking

osteonecrosis of jaw

Question 19

terparatide?

Answer 19

PTH analog (subQ) –> increased OB activity

• • increased bone growth vs. bisphosphonates
• • SE: transient hypercalcemia; maybe increased risk of osteosarcoma

Question 20

allopurinol MOA?

Answer 20

converted to alloxanthine –> inhibits XO

** increased concentrations of azathioprine and 6MP

Question 21

allopurinol uses?

Answer 21

gout

lymphoma and leukemia - prevent tumor-lysis nephropathy

Question 22

pegloticase?

Answer 22

recombinant uricase: uric acid –> allantoin

Question 23

probenecid?

Answer 23

inhibits uric acid reabsorption in PCT
can precipitate uric acid calculi

** inhibits PCN secretion in PCT as well

Question 24

colchicine?

Answer 24

binds tubulin –> inhibit microtubule polymerization
impairs neutrophil chemotaxis and degranulation
gout: acute and ppx

Question 25

salicylates in gout?

Answer 25

DON'T GIVE EM | depress uric acid clearance, especially at lower doses

Question 26

what do TNFa inhibitors predispose to?

Answer 26

infection - esp TB reactivation | needed in granuloma formation and stabilization

Question 27

etanercept?

Answer 27

fusion of TNFa rcptr and IgG1 Fc | used for RA, psoriasis, ankylosing spondylitis

Question 28

infliximab, adalimumab?

Answer 28

anti-TNFa Mab | used in IBD, RA, ankylosing spondylitis, psoriasis