Gout

Question 1

Colchicine mechanism

Answer 1

inhibits tubulin polymerization
blocks leukocyte migration/phagocytosis
-no analgesic properties
-24-48 hours of attack

-limited by side effects-especially at high doses-nausea, diarrhea vomiting

Question 2

uricosurics

probenecid

Answer 2

inhibits renal anion transporter
-promotes uric acid excretion

AE:
1. KIDNEY STONES in high producers of uric acid

Contraindicated:

1. Kidney stones
2. renal insufficiency
3. uric acid overproduction

-many drug interactions

Question 3

Allopurinol
Feboxostat
-presence of tophi

Answer 3

1. Allopurinol Hypersensitivity: rash, fever, eosinophilia, acute renal failure
   -esp high dose/renal failure or taking diuretics–must reduce dose in renal insufficiency
   -HLAB 5801 risk allele-Korean, Han, Chinese, Thai
   (not induced by Febuxostat- 50% hepatic elimination)
2. 6 mercaptopurine and azathioprine interaction–metabolized by xanthine oxidase to inactive metabolite (6 thiouric acid)

Question 4

Can you use aspirin or salicylates?

Answer 4

no

only NSAIDS like indomethacin and naproxen

Question 5

Pegloticase
Use
Mechanism
Limits

Answer 5

use in drug resistant gout
Enzymatic degradation of insoluble uric acid to allanatoin
anti-bodies to drug

PEG-Urase (pig)
IV infusions every 2 weeks