Crystal Arthropathy

Question 1

What causes gout?

Answer 1

> Lesch nyan Syndrome
under-secretion causing hyperuricaemia
over production causing hyperuricaemia

Question 2

what is lesch nyan syndrome?

Answer 2

x linked recessive condition with HGPRT deficiency causing:
> gout
> renal disease

Question 3

what can cause overproduction of uric acid?

Answer 3

> malignancy
> severe exfoliative psoriasis
> inborn error of metabolism
> HGPRT deficiency
> cytotoxic drugs
> ethanol

Question 4

what can cause under-secretion of uric acid?

Answer 4

> hypertension
> renal impairment
> lead poisoning
> dehydration
> starvation
> exercise
> drugs
 - diuretics
 - low dose aspirin
 - alcohol

Question 5

what supplies the body with urate?

Answer 5

> degradation of purines (2/3rds)

> diet

Question 6

how is uric acid eliminated?

Answer 6

> kidney 70%

> biliary tract converted to allantoin

Question 7

how does gout present?

Answer 7

> tophi (uric acid accumulation)
> acutely painful
> lasts 1 week to 10 days
> usually 1st metatarsal joint
> sudden onset
> red
> shiny
> can get peeling of the overlying skin

Question 8

hoe is gout diagnosed?

Answer 8

aspiration chowing needle shaped crystals

Question 9

how is gout managed?

Answer 9

> acute flare:
 - colchicine
 - NSAIDs
 - steroids (IM, IA, oral)
> cardiovascular risk factors
 - purine rich food (fish)
 - obesity

Question 10

when does hyperuricaemia need treatment?

Answer 10

> 2nd attack in one year
> prophylactically prior to malignancy treatment
> first attack and
 - tophaceous gout
 - polyarticular gout
 - renal insufficiency
 - urate calculi

Question 11

how is uric acid lowered in hyperuricaemia?

Answer 11

> XANTHINE OXXIDASE INHIBITOR [allopurinol]
febux osteal
uricosuric agents
canakinumab

Question 12

what are the rules for lowering uric acid in hyperuricaemia?

Answer 12

> wait until acute attack has settled
use prophylactic NSAIDs/steroids until urate levels normalise
adjust allopurinal according to renal function

Question 13

what is the aetiology of pseudogout?

Answer 13

> idiopathic
> familial
> metabolic
> trauma
> incurrent illness

Question 14

how does pseudogout present?

Answer 14

> erratic flares
knee
elderly females

Question 15

what is pseudogout?

Answer 15

> chondrocalcinosis

> phosphate crystals

Question 16

how is pseudogout managed?

Answer 16

> NSAIDs
IA steroids
rest and splint

Question 17

what is the relationship between polymyalgia rheumatica, giant cell arteritis and high ESR anaemia?

Answer 17

giant cell arteritis leads to polymyalgia rheumatica and high ESR anaemia (which in turn leads to polymyalgia rheumatica)

Question 18

how does polymyalgia rheumatica present?

Answer 18

> sudden onset shoulder stiffness (+/- pelvic girdle)
> usually over 70yrs
> F2:1M
> esr more than 45
> anaemia
> arthralgia/synovitis
> general
 - fever
 - malaise
 - weight loss
 - depression

Question 19

how is polymyalgia rheumatica diagnosed?

Answer 19

> compatible history
more than 50 yrs old
ESR more than 50
dramatic steroid response

Question 20

a 68 year old presents with sudden onset shoulder stiffness, anaemia, depression and malaise.
what is your differential?

Answer 20

> POLYMYALGIA RHEUMATICA
> hypo/hyperthyroidism
> fibromyalgia
> bilateral shoulder capsulitis
> underlying malignancy
> myalgic onset of inflammatory joint disease

Question 21

how is polymyalgia rheumatica treated?

Answer 21

prednisolone 15mg per day 18-24 month course as bone prophylaxis