Gout & Pseudogout Flashcards
What is gout?
- inflammatory arthritis
- microcrystal synovitis caused by the deposition of monosodium urate monohydrate in the synovium. It is caused by chronic hyperuricaemia (uric acid > 0.45 mmol/l)
What is the presentation of gout?
- pain: this is often very *significant swelling
- erythema
- 70% affect 1st MTP joint
- Other joints: ankle, wrist, knee
What are the predisposing factors for gout?
Decreased excretion of uric acid:
- drugs i.e. diuretics
- chronic kidney disease
- lead toxicity
Increased production of uric acid:
- myeloproliferative/lymphoproliferative disorder
- cytotoxic drugs
- severe psoriasis
What is the management of acute gout?
- 1st: NSAIDs or colchicine are first-line
- maximum dose of NSAID should be prescribed until 1-2 days after the symptoms have settled + PPI cover
*oral steroids may be considered if NSAIDs and colchicine are contraindicated
*another option is intra-articular steroid injection
if the patient is already taking allopurinol it should be continued
Prophylactic treatment for gout?
Medication:
- Urate-lowering therapy
- Allopurinol first line
- initial dose of 100 mg od, with the dose titrated every few weeks to aim for a serum uric acid of < 300 µmol/l
Lifestyle:
- Reduce alcohol and food high in purines
- Lose weight
What the main finding is found on joint aspiration of gout?
*Negative birefringent, needle shaped crystals
What is pseudogout?
Form of microcrystal synovitis caused by the deposition of calcium pyrophosphate dihydrate crystals in the synovium.
What investigations is needed to diagnose pseudogout? Distinctive feature on investigations?
*joint aspiration: weakly-positively birefringent rhomboid-shaped crystals
What is the management of pseudogoat?
- aspiration of joint fluid, to exclude septic arthritis
* NSAIDs or intra-articular, intra-muscular or oral steroids as for gout