Gout Flashcards
Acute gout
Severe pain and erythema, typically in one joint, follow-up attacks may involve more joints
Chronic tophaceous gout
persistent pain and joint stiffness involving many joints; soft tissue mass of urate crystals in areas of low body temperature; attacks are frequent and there are persistently elevated serum uric acid concerntrations
How is uric acid made in the body
purines break down into xanthine then into uric acid
What is the mechanism of gout?
- water diffuses out of the joint
- uric acid concentration is increased which leads to crystal formation
- inflammatory cascade
What are lifestyle risk factors of gout
obesity, seafood, red meat, alcohol
What are medical conditions that are risk factors of gout
DM and renal disease
What are medication risk factors for gout
thiazide diuretics, low/mod dose aspirin, ACE/ARB
What are the 4 stages of gout
- Asymptomatic
- Acute gouty arthritis
- Intercritical gout
- Chronic recurring gout
What is the treatment for a gout flare
- first line: colchicine, NSAIDs, or corticosteroids
- continue prophylaxis treatment for 3-6 months
How to treat a frequent flare of gout or 1 or more Tophi
- start urate lowering therapy
- first line - Allopurinol
- serum urate goal <6mg/dL
- Start urate lowering therapy during flare instead of after resolution
What are nonpharmacological recommendations for gout
- limit intake of alcohol, purines, and high fructose corn syrup
- Weight loss
What is the approach to managing gout?
Do not start long-term therapy following first gout flare or in those with infrequent flares (<= 2 flares per year
Acute flare treatment/prophylaxis?
NSAIDs, Colchicine, Corticosteroids
Chronic management?
Allopurinol, Febuxostat, Probenecid
What can be done if flare is severe or several joints are effected?
Combination therapy with colchicine, NSAIDs, and oral corticosteroids
What is colchicine MOA?
- Anti-inflammatory
- Prevents migration of neutrophils to sites of inflammation
- Not an analgesic - won’t directly stop pain
What is colchicine efficacy?
50% reduction in pain at 24 hours
What is the dosing for colchicine?
- tablet is 0.6 mg
- 1.2 mg within 12 hours of onset and 0.6 mg 60 minutes later (do not repeat for 3 days)
- Gout prophylaxis - 0.6 mg 1-2 times daily (max 1.2mg/day and wait 12 hours after acute gout flare before resuming prophylaxis)
Adverse effects of colchicine?
GI discomfort and diarrhea
Safety of colchicine?
> 4mg multiple organ failure and death
How does colchicine relate to NSAIDs in terms of pain relief?
More delayed onset of effect than NSAIDs for pain relief
When should corticosteroids be used for gout?
last-line agent
Adverse effects of corticosteroids?
diabetes/hyperglycemia
Nonpharmacologic prevention of recurrent gout attacks?
- Adequate hydration
- Diuretic therapy discontinuation
- low-moderate impact exercise
- restrict purine and alcohol intake
- weight reduction
What are the expectations of preventing gout attacks?
therapy goal - serum uric acid concentration <5-6 mg/dL
Evaluate serum uric acid concentrations every 3 months for the first year then annually there after
What are the Xanthine Oxidase Inhibitors?
1st line - Allopurinol (Zyloprim)
alternative - febuxostat (Uloric)
How do Xanthin Oxidase inhibitors work?
decrease uric acid production, do not lower current uric acid levels, may lead to gout flare
What is allopurinol MOA?
Urate lowering therapy
Inhibits production of uric acid by inhibiting xanthene oxidase enzyme
Allopurinol efficacy?
- prevent recurrent gouty arthritis attacks
- Reduce uric acid concentrations
How often is allopurinol taken?
Daily
Adverse effects of allopurinol?
Well tolerated
Transient rash
Safety concerns of allopurinol?
SJS
decreased excretion of allopurinol when taken with thiazide
What should be done if patient has a rash with allopurinol?
Stop using and don’t try again
When should allopurinol not be used?
asymptomatic hyperuricemia
Should allopurinol be stopped during an acute attack?
No
What is the efficacy of febuxostat?
greater efficacy for reducing uric acid concentration, but no more efficacious for preventing gout flares
What are the adverse effects of febuxostat?
Arthralgias and nausea
What is the safety of febuxostat?
- CI in patients using azathioprine, mercaptopurine, or theophylline
- Higher incidence of cardiovascular events observed compared with allopurinol
What is a specific use of febuxostat?
reduce tophi
Should febuxostat be used in patients with asymptomatic hyperuricemia?
No
What is probenecid MOA?
inhibition of a renal tubular transporter
What is the safety of probenecid?
- Avoid in patients with uric acid kidney stones
- Many drug interactions
What is important to remember when prescribing probenecid?
ineffective in patients with even mild renal insufficiency