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Flashcards in Crystal Arthritis Deck (36)
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1
Q

what is gout?

A

inflammation in the joint triggered by uric acid crystals

2
Q

who more commonly gets gout, F or M?

A

M

rate of gout for F starts to increase after menopause

3
Q

what causes uric acid crystal deposition?

A

hyperuricaemia

encouraged by low temperature of synovial fluid

4
Q

what are the 3 main reasons for hyperuricaemia?

A

excess consumption
over production
under excretion

5
Q

why can psoriasis cause hyperuricaemia?

A

causes increased urate production

6
Q

why can chronic renal impairment cause hyperuricaemia?

A

causes reduced urate excretion

7
Q

why can a high alcohol intake cause hyperuricamia?

A

causes increased urate production

8
Q

why can a high red meat or seafood intake cause hyperuricaemia?

A

causes increased urate production

9
Q

why do diuretics cause hyperthyroidisim?

A

cause reduced urate production

10
Q

in acute gout, usually only one joint is involved, which are the most likely joints?

A
  1. first metatarsalpharyngel (MTP)
  2. ankle
  3. knee
11
Q

compare rates of acute gout settling- treatment or no treatment?

A

no treatment- 10 days

treatment- 3 days

12
Q

compare the serum urate levels of acute to gout to chronic gout?

A

acute gout- urate levels may be normal

chronic gout- urate levels are high

13
Q

compare acute gout to chronic gout in terms of the number of joints involved

A

acute- only one joint involved

chronic- multiple joints

14
Q

why can chronic gout cause renal impairement?

A

uric acid crystallisation can occur in the glomeruli and damage the kidneys

15
Q

what is the gold standard way to diagnose gout?

A

polarising microscopy of synovial fluid

16
Q

what are the 3 main medications used in the treatment of acute gout?

A

NSAIDs
Colchicine
Steroids

17
Q

what treatments are used in the prophylaxis of recurring gout?

A
allopurinol
febuxostat
uricosurics
(2-4 weeks after acute attack)
initiially treat acute attack with NSAID, colchine or steroids
18
Q

what crystals are deposited in joints in pseudogout?

A

calcium pyrophosphate

19
Q

compare the shape of calcium pyrophosphate crystals to uric acid crystals?

A

calcium pyrophosphae- blunt

uric acid crystals- long and sharp

20
Q

what is the treatment of acute pseudogout?

A

NSAIDs
Colchicine
Steroids
Rehydration

21
Q

what is the treatment of chronic pseudogout?

A

no long term treatment, treat acute episodes

22
Q

what is milwaukee shoulder?

A

destructive shoulder arthropathy due to hydroxyapatite crystal deposition in/around joint

23
Q

what is the treatment of hydroxyapatite crystal deposition?

A

NSAIDs
intra-articula steroid injecionts
physiotherapy (to mobilise joint)
partial or total arthroplasty

24
Q

what nucleotides are broken down to form uric acid?

A

purines (adenine and guanine)

25
Q

what is the name of gout affecting the first metatarsalphalangeal (MTP) joint?

A

podagra

26
Q

how does gout present?

A

intensely painful, red, hot swollen joint

27
Q

what diagnosis looks similar to gout but is much more serious?

A

septic arthritis

28
Q

what are gout tophi?

A

painless white accumulations of uric acid which occasionally erupt through the skin near a joint

29
Q

what do uric acid crystals display under polarised microscopy?

A

negative birefringence

30
Q

what is chondrocalcinosis?

A

calcium pyrophosphate deposition in cartilage and other soft tissues
(no acute inflammation)

31
Q

what are the 2 conditions that can occur in calcium pyrophosphate deposition disease?

A

pseudogout

chondrocalcinosis

32
Q

what enzyme do allopurinol and febuxostat work on?

and what is the mechanism?

A

xanthine oxidase

they are xanthine oxidase inhibitors so prevent xanthine being converted to uric acid

33
Q

why should patients on azathioprine not be prescribed allopurinol?

A

interaction causing irreversible bone marrow failure

34
Q

what should you do when giving allopurinol to a patient with renal impairment?

A

lower dose of allopurinol

35
Q

when is febuxostat used over allopurinol in the prophylaxis of gout?

A

in those who cannot tolerate allopurinol

36
Q

what patients should febuxostat be used in caution?

A

patients with ischaemic heart disease