GOUT

Question 1

gouty attack clinical features

Answer 1

sudden onset; nocturnal; precipitating factor; monoarticular; small, peripheral joint; fever

Question 2

gout differential diagnosis

Answer 2

critical: bacterial infection of joint; other: pseudogout, aseptic monoarthritis, trauma; plasma urate level unreliable predictor of gouty attack

Question 3

gout risk factors

Answer 3

OBESITY; high purine (PROTEIN) diet; metabolic factors; excessive alcohol; drug therapy; kidney failure;

Question 4

pathophysiology of gouty attacks

Answer 4

plasma urate - ONE determinant of gouty attack, but inc levels may persist for years w/o attack; slight rise could cause attack

Question 5

deposition of monosodium urate crystals depends on

Answer 5

‘solubilizers’ in plasma; plasma pH (alcoholics -> acidotic); tissue perfusion/temp

Question 6

summary of gout treatment

Answer 6

aspirin competes w/urate for secretion -> inc urate in predisposed ppl! inc fluid intake -> inc excretion; allopurinol - don’t give if prone to attack -> slight inc in purines at start

Question 7

colchicine characteristics

Answer 7

plant alkaloid w/cytostatic properties

Question 8

colchicine pk

Answer 8

oral

Question 9

colchicine pd

Answer 9

binds to tubulin (inhibit microtubule assy) -> depolymerization -> cytostatic effect on leukocytes, inhibit inflammation -> pain relief; NO EFFECT on msu crystals or plasma urate levels

Question 10

colchicine uses

Answer 10

tx acute gouty attack

Question 11

colchicine adverse effects

Answer 11

related to cytostatic properties; acute: GI complaints, pain, DIARRHEA (frequent); chronic: no longterm tx -> alopecia, agranulocytosis, aplastic anemia, myopathy, neuropathy

Question 12

colchicine contraindications

Answer 12

pregnancy

Question 13

uricostatics: allopurinol pk

Answer 13

oral; converted to oxypurinol (alloxanthine) by xanthine oxidase

Question 14

allopurinol pd

Answer 14

competitively inhibit xanthine oxidase -> large dec urate, large inc hypo/xanthine -> more soluble than urate -> dec risk of urate precipitation, inc hypo/xanthine renal excretion

Question 15

allopurinol adverse effects

Answer 15

GI upset; may inc urate at onset; rare: erythema multiforme, stevens-johnson syndrome

Question 16

allopurinol uses

Answer 16

manage chronic gout; NOT in first 1-2 wks after acute episode

Question 17

uricosuric agents

Answer 17

probenecid, sulfinpyrazon, (benzbromarone)

Question 18

probenecid, sulfinpyrazon, (benzbromarone) pd

Answer 18

block tubular reabsorption of urate at therapeutic conc

Question 19

low doses of uricosuric agents…

Answer 19

BLOCK tubular secretion of urate! don’t use after first few weeks of attack

Question 20

probenecid, sulfinpyrazon, (benzbromarone) interactions

Answer 20

probenecid inhibits tubular secretion of penicillin, naproxen, ketoprofen, indomethacin (nsaids) -> can’t tolerate co-tx

Question 21

probenecid, sulfinpyrazon, (benzbromarone) adverse effects

Answer 21

mild; sulfinpyrazone - GI

Question 22

treatment of chronic hyperuricemia

Answer 22

dec of the body urate pool takes months/yrs; maybe lifelong therapy; ensure high fluid turnover; start in symptom-free interval; dec purine-rich food; tx w/uricosuric/static drug; can use nsaid/low dose colchicine at onset of therapy - prevent recurrence; weight loss; urine alkalinization may help -> if overdue -> calcium oxalate stones