Did you know: Gout is the only arthritic disease you can cure- there are many myths about treatment so we’ve made it a bit easier for you to understand…..
1) What is the treatment target for gout?
Normal range of urate on pathology testing is irrelevent to treatment goals
Goal for treatment of Gout 0.36mmol/L but if toplhi are present goal is 0.3mmol/L
2) When should you initiate treatment?
You should initiate treatment if any of the following apply
Tophi present (look of ears elbows fingers toes elbows if present there is a huge bodily burden of urate)
2 or more episodes of gout (60% will have another attack within 12 months)
CKD 2 or worse (ie if eGFR is <90ml/min)
Past kidney stones
3) How should I confirm diagnosis?
If at all possible a crystal diagnosis is the gold standard (patients can quite easily be misdiagnosed as a seronegative arthritis and thus might be exposed to immunosuppressant drugs)
Often a referral to radiology for joint aspiration +/- intraarticular steroid injection
if not refer to rhuematologist (Ingrid Hutton or Phillip Robinson RBH Tues pm)
4) What are the goals of treatment?
twofold firstly treat attack and secondly decrease urate
5) What is the best treatment of an acute attack?
No longer treat to diarrhea
Colchicine 2 tabs rpt in 1 hour then 1 12 hourly or
max daily doses eg Diclofenac 150mg /24 hours
Contraindications If eGFR <30ml/min or Heart Failure NO Colchicine
If patient cannot tolerate NSAIDs the prednisolone is a good alternative
0.5mg/kg for 5-10 days with 2-5 days at full dose then taper for 7-10 days
Intra-articular steroid 40-80mg into knee joint
6) Are there other cautions?
Major interaction of Allopurinol is Azothioprine (AZT)
The previous practice of underdosing of allopurinol in gout for patients with renal failure is outdated however patients with renal failure are at higher risk of Allopurinol Hypersensitivity Syndrome (this is a serious illness potentially fatal like a Stevens Johnson Syndrome – 25% mortality)
Those with HLA B58 are more at risk (2% Caucasian 8% Indian/Subcontinent)
can screen for this HLA at pathology (ask for class 1 alleles HLA B58)
If Asian descent or Asian descent +renal impairment the risk is increased x 500
Most react within 1-2 months (50% by 1 month and 90% within 3 months) IF you start with low doses (as per HANDE guidelines) then the T cells become tolerant and then up titration is possible) The Allopurinol Hypersensitivity Syndrome is not associated with steady state dosing but rather the starting dose in relation to the renal function
Take home message start low and up titrate to be safe
If normal renal function (> 60ml/min) 100mg/day
otherwise consult HANDE guidelines may be as low as 50mg twice weekly
7) Should I start allopurinol during an acute attack?
Actually the best time to start aAllopurinol is under the cover of treatment of acute attack…just start slow
8) What agent should you use for flare prevention when starting allopurinol?
1st line colchicine 0.5mg 1-2 daily OR Naproxen 250mg bd
2nd line prednisone usually 5mg daily but up to 9-10mg daily
9) How long should you continue prophylaxis when starting Allopurinol?
At least 6 months
If no tophi on careful examination continue prophylaxis for 3 months after achieivn serum urate target 0.36mmol/l
If tophi on examination after achieivng serum urate target of 0.3mml/l (this is because the treatment will disturb the the balance between serum urate and body urate
A common treatment protocol if normal renal function and no tophi would be:
100mg allopurinol 3 weeks
200mg allopurinol 3 weeks
300mg allopurinol 3 weeks
then TEST to see if target of 0.36 mmol/l
then test urate levels and renal function every 12 months
sometimes you might need the cover of colchicine 0.5mg + prednisone 5mg as some may not tolerate the effects of prolonged NSAIDs
Naprosyn 1000mg is a great NSAID to choose for flares (and lower dose for prophylaxis as it is the only NSAID that doesn’t increase CVS risk
There is some evidence that if urate is lowered renal function will improve.
Usually allopurinol is increased every 3-4 weeks to a max dose of 900mg
Don’t ever stop allopurinol (unless they get a rash)
You can always back titrate and lower than target urate is not harmful just unnecessary
10) What diet should I recommend for gout patients?
Strict dietary changes are very difficult for people to maintain and the goal is to lower serum urate so dietary advice is best kept simple and practical
Avoid seafood and alcohol and sweetened drinks eg coke (they contain added fructose for which urate is a metabolic byproduct) 90% of people with gout are obese so recommending they cut out sweetened beverages is important
11) What instructions are important for the gout patient?
Gout patients should be given 3 plans
An up titration plan with date for bloods and review
A prophylaxis plan
A plan to manage any potential flare up
Gout is so painful patients need to be very clear and their management or they risk flares and abandon treatment altogether
12) Is there an alternative to allopurinol?
Probenecid and there is a newer agent coming out called Lesinurad
Sometimes if you reach 600mg of Allopurinol you can add probenecid in order to reach target.