Gout

Question 1

what is gout

Answer 1

microcrystal synovitis caused by deposition of MSU in synovium
caused by chronic hyperuricaemia (uric acid > 450 umol/l)

Question 2

acute mx of gout?

Answer 2

first-line: NSAIDs, colchicine

Question 3

when should max dose NSAID be prescribed?

Answer 3

1-2 days after sx have settled
gastroprotection, e.g. PPI, also maybe indicated

Question 4

how does colchicine work?

Answer 4

inhibits microtubule polymerisation by binding to tubulin, interfering with mitosis
also inhibits neutrophil motility and activity

Question 5

colchicine disadvantages

Answer 5

slower onset of action
diarrhoea is main side effect

Question 6

what is used if NSAIDs and colchicine are CI in gout acute mx?

Answer 6

oral steroids - usually prednisolone 15mg/day

Question 7

what should be done if the pt is already taking allopurinol in gout?

Answer 7

continue with allopurinol (don’t stop it)

Question 8

what are indications for urate-lowering hterapy?

Answer 8

give to all pt after first gout attack

particularly recommended if 2 or more attacks in 12mo, tophi, renal disease, uric acid renal stones, prophylaxis if on cytotoxics or diuretics

Question 9

what is first-line in urate-lowering therapy?

Answer 9

allopurinol (100mg od with dose titrated every few weeks to aim for serum uric acid of <300umol/l)

lower initial doses if pt has reduced egfr

consider colchicine or NSAID cover (for 6mo)

Question 10

when should urate-lowering therapy be delayed until?

Answer 10

best delayed until inflammation has settled as ult better discussed when pt is not in pain

Question 11

what is second-line in urate-lowering therapy?

Answer 11

if allopurinol is not tolerated or ineffective, use febuxostat (xanthine oxidase inhibitor)

Question 12

what is third-line in urate-lowering hterapy?

Answer 12

uricase (urate oxidase)
pegloticase (x1 infusion every 2wks) - persistent symptomatic and severe gout despite ULT

Question 13

lifestyle modifications in gout?

Answer 13

reduce alc intake, avoid in acute attack
lose weight if obese
avoid purine-rich food (liver, kidney, seafood, mackerel/sardines, yeast products)

Question 14

what drugs may be stopped in gout?

Answer 14

thiazides

Question 15

why may losartan be suitable in gout management?

Answer 15

has specific uricosuric action so may be suitable for pt who have coexistent HTN

Question 16

why may increasing vitamin C intake improve gout?

Answer 16

decreases serum acid levels

may be recommended either as supplements or normal diet

Question 17

how long do gout flares last?

Answer 17

several days usualy
acute develop maximal intensity within 12h

Question 18

features of a gout flare?

Answer 18

pain - often v sig
swelling
erythema

Question 19

around 70% of first gout presentations affect?

Answer 19

1st MTP, but other commonly affected = ankle, wrist, knee

historically called podagra

Question 20

what can happen if acute episodes of gout are left untreated?

Answer 20

more chronic joint issue

Question 21

ix of gout?

Answer 21

IMMEDIATE
joint aspiration for synovial fluid analysis - needle-shaped -ve birefringent MSU crystals under polarised light (rule out sa)
CRP (rule out sa, in which case would be raised)
x-ray

LATER
uric acid - once acute episode has settled (~2wks) as may be high/normal/low during the attack

Question 22

differentials for a hot, swollen joint

Answer 22

gout
septic arthritis

Question 23

why are cytotoxic drugs a risk factor for gout?

Answer 23

they increase cell breakdown, releasing products degraded into uric acid -> hyperuricaemia (a rf for gout)

Question 24

radiological features of gout?

Answer 24

early sign: joint effusion

punched-out erosions with sclerotic margins in a juxta-articular distribution
overhanging edges
soft tissue swelling

normal joint space until late disease

no periarticular osteopenia (unlike RA)

soft tissue tophi maybe

Question 25

predisposing factors for gout?

Answer 25

decreased uric acid excretion: diuretics, ckd, lead toxicity
increased uric acid production: myelo/lymph proliferative disorder, cytotoxic dtugs, severe psoriasis
lesch-nyhan syndrome

Question 26

what are features of lesch-nyhan syndrome?

Answer 26

hypoxanthine-guanine phosphoribosyl transferase deficiency
x-linked recessive - so only seen in men

features: gout, renal failure, neuro deficits, learning difficulties, self-mutiliation