Ch 47: Gout

Question 1

normal serum urate level

Answer 1

2.0-7.2 mg/dl

Question 2

risk factors

Answer 2

male, obesity, excessive etoh, HTN, CKD, lead intox, adv age, meds that inc urate

Question 3

asx hyperuricemia tx

Answer 3

none

Question 4

acute gout attack tx

Answer 4

monotx with NSAID, sys steroid (or intra-articular), or PO colchicine. if severe: combo tx. ice can help. if on ULT, do not interrupt tx during flare.

Question 5

common gout location

Answer 5

metatarsophalangeal joint (MTP) aka big toe

Question 6

tophi

Answer 6

uric acid crystals that form under the skin in long-term gout

Question 7

chronic ULT

Answer 7

use NSAIDs or colchicine for ppx to reduce risk of gout flare when initiating ULT. 1st line ULT is allopurinol or febuxostat, titrated up to target urate level of <6 mg/dl. 2nd line is probenacid, which can also be added if urate not at goal and at max dose allopurinol/febuxostat.

Question 8

colchicine - brand, dosing, contraindications, warnings, ADRs, notes

Answer 8

colcrys. tx dose: 1.2 mg PO then 0.6 mg in 1 h (do not exceed 1.8 mg in 1 h). do not repeat dose before 3 d. contraindications: combo with pgp or strong 3a4 inhibitor when pt has renal/hep impairment. warnings: GI sx (dec dose if anorexia or diarrhea, V), myopathy risk. ADRs; NVD, myelosuppression, myopathy, neuropathy (dose related). start <36 h of onset of sx for tx. If taking ppx dose, wait 12 h after tx dose to resume ppx dose.

Question 9

NSAIDs approved for gout + notes

Answer 9

indomethacin (indocin), naproxen (Naprosyn), sulindac (clinoril) BID, celecoxib (celebrex) BID. avoid in severe renal disease. CVD risk (highest with celebrex)

Question 10

Steroids approved for gout, admin forms, dosing

Answer 10

prednisone/prednisolone, methylprednisolone, triamcinolone. PO/IM/IV/intra-articular or as adrenocorticotropic hormone. pred 0.5/mg/kg/d PO x5-10 d (no taper) OR 0.5 mg/kg/d x2-5 d then taper over 7-10 days.

Question 11

allopurinol - brand, warnings, ADRs, notes, MOA

Answer 11

Zyloprim, +lesinurad is Duzallo. warnings: hypersens rxns including severe rash, HLA-B*5801 testing prior to use. ADRs: rash, acute gout attacks, ND (take after meal to reduce). higher doses used for tumor lysis syndrome. use with colchicine or NSAID for first 3-6 mo to ppx gout flares, xanthine oxidase inhibitor to dec uric acid production

Question 12

febuxostat - brand, warnings, ADRs, notes, MOA

Answer 12

Uloric. warnings: hep tox. ADRs: rash, nausea, inc LFTs. has lactose. use with colchicine or NSAID for first 3-6 mo to ppx gout flares, xanthine oxidase inhibitor to dec uric acid production

Question 13

lesinurad - brand, BBW, indicaiton, ADRs, MOI

Answer 13

Zurampic. BBW: acute renal failure esp if monotx, only use with XOI. ADRs: inc scr. indication: use with XOI if UA goals not reached with XOI alone. MOA: inhibit reabsorption of uric acid in kidneys, to inc uric acid excretion

Question 14

probenecid - warnings, notes, MOA, indication

Answer 14

G6PD deficiency warning for hemolytic anemia. can be used to inc beta lactam levels by dec beta lactam renal excretion. MOA: inhibit reabsorption of uric acid in kidneys, to inc uric acid excretion. indication: 2nd line if contraindication to XOI or adjunct if not at goal with max XOI.

Question 15

pegloticase - brand, form, BBW, contraindication, indication, warnings, MOA

Answer 15

krystexxa. IV only q2wks. BBW: anaphylactic rxns, premed with antiHAs and steroids, risk is higher if urate >6. contraindications: g6pd deficiency. warnings: acute gout flares, start NSAID or colchicine 1 wk prior to infusion and continue for at least 6 mo. do not use in combo with allopurinol or febuxostat, indication to replace, d/t inc risk of anaphylaxis. MOA: converts urate to allantoin (water solu metabolite) for excretion

Question 16

rasburicase - brand, BBW, indication, MOA

Answer 16

elitek. BBW: anaphylaxis. indication: hospitalized cancer pts with very high uric levels. MOA: urate oxidaseconverts urate to allantoin (water solu metabolite) for excretion

Question 17

tumor lysis syndrome

Answer 17

if tx: ULT + correct ‘lytes. ppx for high-risk pts receivign certain types of chemo is usually high dose allopurinol.

Question 18

drugs that inc urate

Answer 18

asa, diuretics, niacin, pyrazinamide, ribavirin, calcineurin inhibitors (tacrolimus and cyclosporine)