Gout/pseudogout Flashcards
Crystals in acute gout called?
Monosodium urate monohydrate
Crystals in pseudogout called?
Calcium pyrophosphate dihydrate
plasma urate target
below 0.3
But takes a long time for crystal load to decrease after you get serum levels under control, so may still have attacks
WHilst this is going on, could consider prophylactic colchicine 0.5 mg daily or BD for first 6 months
What does the fluid look like in pseudogout
often bloodstained
hand joints but also big joints
RA and pseudogout assoc?
neg assoc
classic foot joints in pseudogout
MTP 2 and 3
treat pseudogout
aspirate joint immpobilise with splint NSAIDS IA steroids systemic steroids
educate, exercise, reduce obesity, simple analgesia
what is negatively birefringent?
YeLLow when paraLLel to polarising light = neg
Yellow up hill tilt, blue downhill tilt if see
what is BCP disease?
basic calcium phosphate hydroxyapatite
need EM for diagnosis
present with shoulder or rotator cuff or hip or knee or wrist tendonitis/bursitis
can have local tendon rupture
SHoulder x ray with calcified tendon- this is it
Can cause massive blown up shoulder because of bloody effusion- milwaukee shoulder
Gout RF
metabolic syndrome insulin resistance obesity cardiac failure organ transplant diuretics CKD
Mechanism of hyperuricaemia
usually from renal under-excretion
Why is gout more common in men?
Oestogen promotes excretion uric acid
Urate is a metabolic product of what
purine
(most from endogenous load from tissue breakdown, 30% denovo via PrPP synthase or from diet)
Excretion into gut is via ABCG2
Which diet thing PROTECTS against gout
dairy
How many attacks will have high uric acid?
half only!
Cyclosporine and gout
cyclo lowers urinary clearance
Key mediator gout inflammation
IL-1B
ACute gout
NSAIDS
colchicine
second line
IACS
systemic CS
MOA colchicine
affects NEUTROPHIL function by inhibiting microtubule polymerisation-essential for mitosis
What does nasty overdose of colchicine look like?
First GI sx
Then rhabdo and BM failure
What do you give for chronic tophaceous gout
cholchicine 0.5-1mg dailuy (though beware neuromyopathy long term)
NSAID
CS
Il-1 inhibitor (Canakinumab)
colchicine in renal impairment
allopurinol in renal impairment
Colchicine:
not for acute attack if taking prophylactic colchicine and crcl under 80
If cr cl under 30, cannot repeat within 2 weeks
CAN use but lower dose for prophylaxis
allopurinol:
start low and titrate up according to target under 0.36 or 0.3 if tophi present
strongest comorbid assoc with gout is
hypertension
the antihypertensives that increase urate clearance are losartan and amlodipine
