Gout Flashcards
What does the epidemiology of gout look like?
- Increased age and males at risk
- Linked to comorbid conditions, diet, and medications
What is the concentration where uric acid starts becoming insoluble?
6.7 mg/dL
What disease states can promote hyperuricemia?
- Diabetes
- HLD
- Obesity
- Renal insufficiency/CKD
- HTN
- Organ transplantation
- CHF
What are uricosuric foods/drinks? (can lower uric acid)
- Coffee
- Dairy
- Vitamin C
What foods/drinks can raise uric acid?
- Meat
- Seafood
- Beer/liquor
- Soft drinks
- Fructose
What medications can raise uric acid?
- Thiazides
- Loops diuretics
- Nicotinic acid
- Low dose aspirin
What medications can lower uric acid?
Losartan (use over thiazides)
Fenofibrate (use over nicotinic acid)
What does a gout flare look like?
- <24 severe pain, erythema, swelling
- Single or multiple joints (usually big toe)
What can exacerbate gout flares?
- Alcohol
- High purine ingestion
- Stress
- Certain medications (including UA lowering)
How is acute gout treated?
(Reduce pain and duration of attacks)
NSAIDs
Colchicine
Corticosteroids (oral, IA)
When should NSAIDs be used for a flare?
<24h of flare onset
When should you avoid NSAIDs?
- Renal insufficiency/failure
- Bleeding disorders or anticoagulated
- PUD
- CHF
- Age >75
How should colchicine be dosed for a flare?
1.2 mg PO then 0.6 mg 1 hour later
(may require more)
How should colchicine be dosed for prophylaxis?
0.6 mg PO QD or QOD
When should you avoid colchicine?
- GI problems
- Renal dysfunction/elderly (rhabdomyolysis risk)
- CYP3A4, PGP, fibrates, statins (myopathy)
- Severe hepatic impairment
- Dose adjust for renal/hepatic impairment
T/F: you must lower the dose of colchicine if a patient is on a CYP3A4/PGP inhibitor and has renal failure
FALSE: it is contraindicated in this situation
Which strong CYP3A4 inhibitors interact with colchicine?
- Clarithromycin
- Darunavir/ritonavir
- Itraconazole
- Ketoconazole
Which moderate CYP3A4 inhibitors interact with colchicine?
- Diltiazem
- Erythromycin
- Fluconazole
- Verapamil
Which PGP inhibitors interact with colchicine?
- Cyclosporine
- Amiodarone
- Ranolazine
How should colchicine be adjusted with strong CYP3A4 inhibitors?
Acute: 0.6 mg then 0.3 mg 1 hour later, dose repeated no earlier than 3 days
Prophylaxis: 0.3 QOD to 0.3 QD
How should colchicine be adjusted with moderate CYP3A4 inhibitors?
Acute: 1.2mg, dose repeated no earlier than 3 days
Prophylaxis: 0.3-0.6 mg QD
How should colchicine be adjusted with PGP inhibitors?
Acute: 0.6 mg, dose repeated no earlier than 3 days
Prophylaxis: 0.3 mg QOD to 0.3 QD
How should intra-articular triamcinolone be dosed?
Large joint (knee): 40 mg
Medium joint (wrist, ankle, elbow): 30 mg
Small joint (toe, finger): 10 mg
When should steroids be used?
Only 1-2 joints involved (intra-articular or oral)
When are SYSTEMIC steroids required?
Polyarticular attacks
When should you avoid steroids?
- DM
- CHF
- GERD
- PUD
T/F: Steroids can be used in renal impairment
TRUE
What drugs increase the risk of rash with allopurinol?
- Amoxicillin
- Thiazides
- Ampicillin
- ACEi
What should you do if you develop a rash with allopurinol?
Discontinue -> might progress to SJS or DRESS
What drugs should be avoided with allopurinol?
6-MP, azathioprine, theophylline, drugs that increase risk of rash
What should you do if a patient is on allopurinol and warfarin?
Decrease their dose of allopurinol
How is allopurinol dosed?
100 mg QD usually, increase q2-5 weeks until uric acid <6 mg/dL
50 mg QD for CKD stage 4 or worse
Max 800 mg QD
When should you avoid febuxostat?
- CrCl <30 mL/min
- CV disease
T/F: Febuxostat can be used as monotherapy anytime
FALSE: should be used with colchicine and an NSAID to prevent flares for the first 6 months
T/F: Chronic therapy does not need to be stopped during a flare
TRUE
What is the BBW on febuxostat?
Cardiovascular death with established CV disease
What are contraindications to febuxostat?
6-MP, azathioprine, or theophylline
When should probenicid be avoided?
- CrCl <50 mL/min
- History of nephrolithiasis
- Use of penicillin, methotrexate, carbapenems, salicylates
How should pegloticase be given?
IV 8 mg every 2 weeks for at least 2 hours
Premedicate with antihistamines and corticosteroids
Use with low dose colchicine or NSAIDs for first 6 months to prevent flares
What is the BBW for pegloticase?
Infusion reactions
What indicates a need for chronic therapy?
At least 1:
- Subcutaneous tophi
- Radiographic evidence of damage from gout
- Frequent flares (at least 2 per year)
When can chronic therapy be considered?
- History of 1 attack but less than 2 attacks per year
- First gout flare with CKD (stage 3+), UA >9 mg/dL, urolithiasis
T/F: Uric acid lowering treatment should be started during the flare if it is determined to be indicated
TRUE
What is the first line agent for chronic therapy?
Allopurinol
When should UA be monitored?
Every 2-5 weeks with increases in ULT intensity until goal is reached
What is the general treatment flow chart for chronic therapy?
Allopurinol or febuxostat titrated to maximum dose, then add probenecid if needed
When should flare prophylaxis be started?
When ULT is started
Continue for 3-6 months based on resolution of symptoms and presence of tophi
When is prednisone or prednisolone indicated for prophylaxis?
NSAIDs/colchicine not tolerated or contraindicated
When should we consider combination therapy for a gout flare?
- Polyarticular attack
- Not responding to monotherapy
Can you use colchicine for a flare if they’re already using it for prophylaxis?
YES, as long as they haven’t used colchicine to treat a gout flare in the past 14 days
How should steroids be dosed for a flare (not intra-articular)?
Prednisone 0.5 mg/kg per day for 5-10 days
Which combination therapy should we avoid?
NSAIDs + PO steroids
