common inflammatory arthritis

deposition of monosodium urate crystals

4% over 20 have gout

40% of people with gout have cardiovascular diseae and or diabetes

complex interplay:

genetic

male

maori/polynesian

environmental

stages of gout

• Asymptomatic hyperuricaemia

  • biochemical finding

  • associated;

    • hypertension

    • insulin resistance and DM

    • kidney disease

    • increase cardiovascular risk

  • treatmnet not currenlty recommended

• Acute attack

  • rapid onset of joint pain

    • swelling and eryhtema

  • symptoms peak 12-24hrs

  • urate levels may be misleadingly normal in 11-49% of people

• Chronic tophaceous gout

  • recurrent gout untreated or incompletely managed with urate lowering treatment

  • tophi

  • more freuqnet anttcks

  • increase number of joints involved

  • gradual worsening of inlammatory artritis, erosive joint damage and in some cases urate neprhopathy

communication

• assess patient’s current knowledge

  • what have been told about gout

  • how noramlly manage acute attack

• build on knowledge

  • what gout is

  • difference between acute and preventative treatments

  • lifestyle aspects

• Check patient has understood

myths

• not all about food

  • although etoh(beer), read meat, offal and seafood (shellfish, oily fish), fructose and sucrose sweetned drink

• cann exercise if got gout

  • aerobic exerise may temporarily increase urate levels

  • but will be beneficial in long term

  • cardiovacular risk

Management

Acute attack

• NSAID

  • naproxen 500mg repeated 8-12 hrs then bd on following day tapering dose as attack resolves

  • +/- PPI

• Corticosteroids

  • prednisone 20-40mg daily gradually reduced over 10-14d

  • intra-articular injections if 1-2 joints affected

• colchicine

  • (low dose)

  • most effective when started early (within 12hrs)

  • 1mg stat

    • 0.5mg six hourly

    • max 2.5mg/24hrs on first day

    • 1.5mg on subsequent days

    • max 6mg over 4 dyas

      • limit prescription to 12 tabs only

  • relative CI

    • CrCl \<60

    • hepatic impairment

    • elderly

    • weight \<50jg

Lifestyle

• ideal weight

• 2L H2O

• exercise moderatley

  • during acute attack;

    • rest elevated

    • cool

• Include low fat dair, soy, vege sources of protein

• avoid:

  • dehydration

  • etoh

  • foods rich in purines

  • soft drinks with fructose or sucrose

Prophylaxis

achieve urate \<0.36 (lower target 0.3 recommended in some international guidelines)

(in order)

• Allopurinol

  • first line

  • pharmacology

    • block conversion of hypoxanthine and xanthine to urate

  • 2weeks after acute attack

  • concurrent wiht NSAID (250mg bd)

    • 3-6 months after achieving serum urate level of ≤ 0.36

  •  starting dose = 1.5mg per unit of eGFR

• Probenecid

  • uricosuric drug

  • effective as monotherapy

  • start at 250mg bd increase to 500mg bd

  • if urate target not achieved

    • increase 1g bd

  • can combine with allopurinol

  • CI in history of kidney stones

    • all patients drink 2L /day

• Febuxostat

  • 80mg od to start - increase to 120mg

    • recheck urate 2-4wk after starting

    • co-prescribe with lose dose colchicine or low dose NSAID

    • monitor LFT - initiiation then 1-3 mo after starting

  • mechanism/pharmacology

    • potent

    • non purine

    • selective inhibitor of xanthine oxidase

      • inhibits production of uric acid

        • prevents normal oxidation of purines to uric acid

    • similar mechanism to allopurinol but more potent

    • half life = 5-8hrs therefore suitable for once daily dosing with or without food

  • Special authority

    • patient >0.36 urate despite allopurinol 600mg/day and probenecid

    • or intolerable side effects

    • or both:

      • renal impairment and urate >0.36 despite optiaml therapy and

      • CrCl ≤ 30ml/min

  • adverse reactions:

    • naeusa

    • diarhroea

    • headache

    • rahs

    • gout flares

    • LFT abnormalities

      • ALT 3x ULN

      • ?lcincal signifiance

      • request LFT prior to starting

  • use with caution

    • cardiovascualr disease

  • prophylaxis essential during treatment initiation

  • ddoesn’t need dose adjustment mild - mod renal impairment

    • > 30mL/min

    • eliminated both liver and renal

• Benzbromarone

  • uricosuric agent

    • increase urate excretion by kidney

  • 100-200mg more effective than 1g probenecid daily

  • similar to 300-600mg daily allopurinol

  • mesaure LFTs frequently

    • montly first 6mo at least

  • more effective ?in polynesion

  • special aurthority

  • section 29 - need patient consent