Chapter 60: Gout Flashcards
What is gout?
buildup of uric acid (UA) crystals in the joints
Uric acid is produced as an end-product of
purine metabolism
Name for uric acid crytals in the joint
tophi
Which joint does gout typically occur in
Metatarsophalangeal joint (MTP = big toe)
Risk factors for gout
male sex, obesity, excessive alcohol consumption
Drugs that can increase uric acid and exacerbate gout
aspirin (lower doses)
CNIs
Diuretics
Niacin
pyrazinamide
some chemos and pancreatic enzymes
Foods to avoid in gout
Organ meats, high-fructose corn syrup and alcohol
limit fruit juices, table sugar, sweetened drinks, lamb, pork, seafood
asymptomatic hyperuricemia is treated with what drugs
it is not treated
Once a gout attack occurs, UA should be lowered to
< 6 mg/dL
Which drugs can be used for an acute gout attack
NSAID, steroid or colchicine
targeting pain and inflammation
If the gout attack is localized to one or two joints, what can be helpful
An intra-articular steroid injection
Colchicine brand name
Colcrys
Dosing for colchicine
Two 0.6 mg tabs followed by 0.6 mg in 1 hr
(max 1.8mg in 1 hr or 2.4 mg/day)
colchicine max dose
do not exceed 1.8 mg in 1 hr
or 2.4 mg in one day
Colchicine CI
Do not us in combination with a P-gp or strong 3A4 inhibitor
FATAL toxicity can occur
colchicine warnings
myelosuppression, myopathy risk
colchicine side effects
Diarrhea, nausea, myopathy, neuropathy
colchicine should be started within __ hrs of symptoms onset for treatment
36
With colchicine, wait __ hrs after a treatment dose before resuming ppx dosing
12
Indomethacin brand name
Indocin
Which NSAIDs can be used in gout
Indomethacin, Naproxen, Celecoxib
Which steroid can be given intra-arcticular if 1-2 large joints are involved
Methylprednisolone
If XOI do not work well enough and UA remains > 6 mg/dL in acute gout flare, what can be done
- add probenecid or lesinurad
- Replace XOI with IV pegloticase (Krystexxa)
When starting chronic uric acid lowering therapy (allopurinol or febuxostat), which drugs should be used as ppx for 3-6 months to reduce the risk of attacks
Colchicine or NSAIDs
Patients who are at high risk of a severe allopurinol hypersensitivity reaction should be screened for which allele prior to use
HLA-B*5801
Which drug can be used as a second-line agent if XOI are CI or not tolerated or can be added when the UA level is not at goal
Probenecid
also, lesinurad when XOI is inadequate, but must be used with XOI
Probenecid MOA
Inhibits the reabsorption of UA in the proximal tubule of the nephron, which increases UA excretion
Probenecid requires adequate ____ to be effective
renal function
Which drug is reserved for severe, refractory gout cases
Pegloticase
MOA of pegloticase
Increases UA conversion to allantoin
recombinant uricase enzyme
Xanthine Oxidase Inhibitor MOA
decrease UA production
allopurinol and febuxostat
Allopurinol warnings
Hypersensitivity reactions including severe rash; HLA-B*5801 testing prior to use & do not use drug if positive, hepatotoxicity
Allopurinol SE
Rash, acute gout attacks, nausea
Febuxostat is limited to which population
Those who cannot tolerate allopurinol or allopurinol is not effective
Febuxostat warnings/SE
Increased LFTs, hepatotoxicity, increased thromboembolic events, serious skin reactions
Probenecid can be used to increase ____ levels
beta-lactam
How is pegloticase administered
IV
Pegloticase BW
anaphylactic reactions - monitor and premedicate with antihistamines and steroids
Pegloticase CI
G6PD deficiency
Pegloticase cannot be used in combination with what other gout drugs due to increased risk of anaphylaxis
allpurinol, febuxostat, probenecid
Allopurinol and febuxostat increase the concentration of ____, the active metabolite of ____
mercaptopurine
azathioprine
allopurinol brand name
Zyloprim, Aloprim
What drug is used for tumor lysis syndrome?
rasburicase
contraindications of rasburicase
G6PD deficiency
mechanism of tumor lysis syndrome (TLS)
chemo –> lysed cells –> increased purines –> increased uric acid –> acute gout and significant electrolyte abnormalities –> renal failure, cardiac arrhythmias, seizures, death
