gout . Flashcards
what is gout
erosive inflammatory arthritis caused by the deposition of monosodium urate crystals into joints and soft tissues
what is the cause of gout
usually high serum uric acid levels (hyperuricaemia)
causes of hyperuricaemia
increased urate production and/ or reduced urate excretion
what are causes of increased urate production
high dietary purine intake (red meat, corn syrup)
alcohol
psoraisis
inherited enzyme defects (dontleaarn specifics - usually an unknown deficiency, idiopathic)
causes of reduced urate excretion
chronic renal impairment
volume depletion e.g. heart failure
hypothyroidism
diuretics
cytotoxics e.g. cyclosporin
risk factors for gout
age - rare under 20, decreases over 80
men (oestrogen is protective, women after menopause)
describe the pathophysiology of gout
excess uric acid - more purine breakdown
gout = acute inflammatory response to increased MSU crystals
chronic gouty arthritis and gouty tophi = chronic granulomatous inflammatory repsonse
histology of gouty tophi
eosinophilic debris and inflammation (giant cells)
clinical presentation of acute gout
first MTP is classic first site of disease, ankle and knee are other common
severe pain, hot swollen joint (may mimic septic arthritis)
sudden onset
settles in 10 days with no treatment, 3 with treatment
clinical presentation of chronic tophaceous gout
gouty tophi - painless accumulations of uric acid
MCP, PIP and DIPs
often diuretic associated
may get acute attack
what can chronic gout lead to
destructive and erosive arthritis
Ix used in suspected gout
bloods - serum uric acid, inflammatory markers, renal function
aspiration of synovial fluid
X rays in long standing
blood results in gout
raised serum uric acid - may be normal during an acute attack
raised inflammatory markers
what can be seen on x ray in long standing gout
erosion
why would you aspirate synovial fluid in gout
rule out sepic arthritis in cute disease
gram stain and culture
