gout Flashcards
gout is a result of ___
overproduction and underexcretion of uric acid
the enzyme that converts purines to uric acid
xanthine oxidase
non modifiable risk factors gout
male, elderly, living in developed countries, genetics
modifiable risk factors gout
diet high in purine (red meat, organ meat, shrimp)
high fructose corn syrup
alcohol (beer, wine)
medications
obesity
HTN, HLD, CKD
what drug INCREASES uric acid excretion
losartan
what drugs cause UNDEREXCRETION of uric acid
low dose ASA
thiazide and loop diuretics
levodopa
tacrolimus and cyclosporine
what, other than drugs, causes underexcretion of uric acid
renal impairment, HTN, alcohol, dehydration
what causes overproduction of uric acid
diet, cytotoxic medications, psoriasis, sickle cell disease, lympho/myeloproliferative diseases
what is the gold standard for gout diagnosis
aspiration of synovial fluid or tophi
serum uric acid > __ is gout
6.5-6.8 mg/dL
when is the best time to check serum uric acid
2 weeks after a flare
clinical presentation gout
usually presents as an acute flare; intense joint pain that comes on suddenly/middle of night; joints are swollen, painful, red, warm to touch
____ is a sign of chronic gout
tophi
what are the 4 stages of gout
-asymptomatic
-acute gouty arthritis
-inter critical gout
-chronic recurrent gout
what are the points of asymptomatic gout
serum uric acid levels are >6.8 but no history of gouty attack
does asymptomatic gout warrant treatment
no
what is inter critical gout
the asymptomatic period between attacks
what characterizes chronic recurrent gount
the presence of tophi, persistent joint stiffness and inflammation, radiographic erosions
complications of gout
joint damage and deformity
kidney stones
kidney disease/failure
psychological and emotional problems
goal serum uric acid level
<6 mg/dL
initiate pharmacological therapy within __ hours of an acute gout attack
24
first line agents for acute gout attack
NSAIDs, colchicine, steroids
true or false: you should stop established urate lowering therapy during an acute gout attack
false
which NSAIDs are rec in acute gout attack
sulindac
indomethacin
naproxen
box warning NSAIDs
increase risk of CV thrombotic events including MI/stroke
___ doses of NSAIDs are needed for gout to treat inflammation and pain
higher
naproxen dose
500 BID
indomethacin dose
50 TID
sulindac dose
200 BID
colchicine mech
interferes w/ migration of neutrophils to sites of inflammation that have been induced by deposits of urate crystals in synovial fluid
colchicine dosing regimen
1.2 mg initially followed by 0.6 mg one hour later
0.6 mg BID until flare resolves
adverse effects of colchicine
n/v/d, abdominal pain, muscle pain/weakness
drug interactions colchicine
CYP3A4 inhibitors and p-glycoprotein inhibitors
disease interactions colchicine
severe hepatic impairment or CrCL<30 + dialysis
prednisone dose
30-40 mg/d until resolution then taper 5 mg each day for 7-10d
intraarticular steroid for gout
triamcinolone 10, 30 or 40 mg
IM triamcinolone 60 mg followed by PO corticosteroid if multiple joints
when is chronic urate lowering therapy indicated
1 or more subcutaneous tophi
2 or more attacks per year
evidence of radiographic damage
first line urate lowering therapy
allopurinol
alternative XOI
febuxostat
alternative to XOI
probenicid
add on therapy
lesinurad
allopurinol dosing
start 100 mg/day (50 if CrCL<60)
increase by 50-100 every 4 weeks (max 800)
what to tell the patient when starting XOI
acute gout flares during initiation
monitoring for allopurinol
rash, diarrhea, nausea, LFTs, neutropenia
allopurinol hypersensitivity syndrome
TEN and SJS concern
febuxostat dosing
40 mg daily
if uric acid still >6 mg/dL after 2 weeks, increase to 80 mg daily
cautions with febuxostat
ischemic heart disease or CHF
allopurinol and febuxostat can precipitate a ___
gout attack
when starting XOI, you should
add one of the following:
colchicine
low dose NSAID
low dose glucocorticoid
probenecid mechanism
inhibits tubular urate reabsorption in kidneys
probenecid dosing
250 mg po bid
increase every 4 weeks up to max 1000 mg BID until goal urate
counseling probenecid
increase fluid intake to prevent kidney stones
probenecid contraindications
history of urolithiasis (can increase kidney stones)
CrCL<50
lesinurad main point
must be used in combo with a XOI
lesinurad mech
inhibits the function of renal apical transporters that facilitate reabsorption of uric acid
lesinurad dosing
200 mg daily with food, water, XOI
last line agent gout
pegloticase
pegloticase when to use
if goal of SU<6 is not achieved, d/c the other therapies. only if gout dx burden is severe and refractory/intolerant to other options
pegloticase dosing
8 mg IV q2 weeks
