Crystal arthropathies Flashcards
Gout vs pseudogout
Gout: urate crystals, negatively birefringent, needle crystals
Pseudogout: calcium pyrophosphate crystals, positively birefringent, rhomboid shaped crystals
Treatment for acute gout
Naproxen first line
If contraindicated give colchicine
If renal impairment give steroids
Treatment for chronic gout
Allopurinol with initial cover by steroids/NSAID/colchicine
MoA of allopurinol
Xanthine oxidase inhibitor therefore no effect in acute
CI for allopurinol
Azathioprine as leads to very high 6-MP levels
How does gout progress over time
Acute episodes more severe
More joints affected
Periods between acute episodes shorten
Appearance of gout
Pain, erythema, stiffness and swelling of one joint
Tophi due to urate crystal deposition
X ray appearance
Juxta-articular punched out erosions
What can precipitate attack of gout
Trauma
Surgery
Diuretics (thiazides)
Infection
What should you screen for in someone with chronic gout
CKD
Hypertension
Diabetes
Dyslipidaemia
Lifestyle advice in gout
Avoid alcohol, purine rich meat ad low dose aspirin
Lose weight
Side effects of allopurinol
Rash
Fever
Neutropenia
When should gout prophylaxis be initiated
More than 1 attack within 1 year
Tophi
Renal stone
Risk factors for pseudogout
Hyperparathyroidism
Haemochromatosis
Hypophosphataemia
