Crystal arthropathy- gout Flashcards
(13 cards)
what is gout
a form of microcrystal synovitis caused by the deposition of monosodium urate monohydrate in the synovium
caused by chronic hyperuricaemia
drugs that cause gout
diuretics: thiazides, furosemide
ciclosporin
alcohol
cytotoxic agents
pyrazinamide
aspirin
presentation of gout
pain
swelling
erythema
flare ups last several days
70% affect 1st metatarsophalangeal joint
investigations in gout
uric acid: > 360umol/L
synovial fluid analysis: needle shaped negatively birefringent monosodium urate crystals under polarised light
radiological: joint effusions, punched out erosions, eccentric erosions, soft tissue tophi
acute management of gout
NSAIDs or colchicine first line
oral steroids if NSAIDs and colchicine contraindicated
contraindications for colchicine
reduce dose if eGFFR 10-50
avoid if eGFR < 10
main side effect is diarrhoea
indications for urate lowering therapy
offer to all patients after their first attack of gout
urate lowering therapy
allopurinol first line- titrate to serum acid level < 360
febuxostat
lifestyle modifications to reduce gout
reduce alcohol intake
lose weight
avoid food high in purine: liver, kidneys, seafood, oily fish and yeast products
what is pseudogout
form of microcrystal synovitis caused by the deposition of calcium pyrophosphate dihydrate crystals in the synovium
risk factors for pseudogout
usually associated with increasing age
patients under 60 usually have underlying risk factors:
- haemochromatosis
- hyperparathyroidism
- low magnesium, low phosphate
- acromegaly, wilson’s disease
features of pseudogout
knee, wrist and shoulder most commonly affected
joint aspiration: weakly-positively birefringent rhomboid-shaped crystals
xray: chondrocalcinosis
management of pseudogout
aspiration of joint fluid
NSAIDs or intra-articular, intra-muscular or oral steroids
