Flashcards in Crystal arthropathies Deck (13):
What is gout?
Deposition of urate crystals (negatively birefringent, needle shaped)
Acute inflammatory response with phagocytosis of crystals
What is the cause of hyperuricaemia?
-increased urate production
-reduced urate excretion
INCREASED URATE PRODUCTION
Inherited enzyme defects
Alcohol (beer, spirits)
High dietary purine intake (red meat, seafood, corn syrup
REDUCED URATE EXCRETION
Chronic renal impairment
Volume depletion eg heart failure
Cytotoxics eg cyclosporin
-what is seen in gout?
-how long does it take to settle with/without treatment?
-what is the nature of onset?
Usually monoarthropathy:- 1st MTP > ankle > knee
Settles in about 10 days without treatment
Settles in about 3 days with treatment
Abrupt onset, often overnight
May have normal uric acid during acute attack
What is chronic tophaceous gout?
-what is this assoc. with?
A chronic form of gout. Nodular masses of uric acid crystals (tophi) are deposited in different soft tissue areas of the body.
Often diuretic associated
High serum uric acid
Tophi may ulcerate and extrude uric acid
May get acute attacks
What investigations are done for gout?
Serum uric acid raised (may be normal during acute attack)
Raised inflammatory markers
Polarised microscopy of synovial fluid
Renal impairment (may be cause or effect
What is the acute treatment of gout?
What is the treatment for gout prophylaxis?
Allopurinol – 1st line
Febuxostat – 2nd line
Start 2-4 weeks after acute attack
If start acutely ureate drops quickly and this can cause a flare up as a big change so wait until calmed down. Then you taper up until serum ureate becomes normal.
Require cover with NSAID etc
-what is this?
All the ‘P’s
-pyrophosphate (calcium pyrophosphate)
-positive alignment needles
-how is this different from gout clinically??
Commoner in elderly
Chondrocalcinosis increases with age
Related to osteoarthritis
Affects fibrocartilage - knees, wrists, ankles
What is the pathogenesis of pseudogout?
Acute attacks related to shedding of calcium pyrophosphate crystals (pseudogout)
Calcium pyrophosphate crystals-envelope shaped, mildly positively birefringent
Marked rise in inflammatory markers
What is the treatment for pseudogout?
What is hydroxyapatite?
-who does this affect?
What is it?
Hydroxyapatite crystal deposition in or around the joint.
Release of collagenases, serine proteinases and IL-1
Acute and rapid deterioration.
Females, 50-60 years