crystal diseases Flashcards
what is gout
inflammation of a joint caused by uric acid crystals
how do crystals form in gout
from purines (adenine and guanine) normally excreted from kidneys, this causes too much urea in blood which causes crystals
who is likely to get gout
obese, white men
what causes hyperuricaemia
increased urate production, decreased urate excretion
what causes increased urate production
enzyme defects, psoriasis, haemolytic (cancer), alcohol, diet (red meat and seafood)
what causes decreased urate excretion
renal disease, volume depletion eg HF, hypothyroidism, diuretics
what are the symptoms of acute gout
monoartropathy, common in big toe, abrupt onset (usually at night), painful tender and swollen
what happens in chronic gout
chronic joint inflamm, high serum uric acid, usually diuretics, Tophi, 2 or more bouts a year
what investigations can be done for gout
joint microscopy aspiration, serum uric acid, inflamm markers, renal function, X ray
what treatment is there for acute gout
NSAIDs eg naproxen, colchicine, steroids, can settle in 10 days with no treatment
what treatment is there for prophylaxis of gout
allopurinol and febuxostat (xanthase oxidase inhibitor),
when should prophylactic gout treatment be started and what must it always be prescribed with
2-4 weeks after an acute attack, always cover with NSAIDs
what is seen on joint microscopy aspiration of gout
needle crystals, negative birefringence, polarizing microscopy
what is CPPD/ pseudogout
calcium phyrophosphate deposits in hyaline and fibrocartilage, mimicking gout
what joints are commonly affected in CPPD and who normally gets it
elderly with familial pattern, knees, wrists, ankles
