Crystal arthropathy

Question 1

What is gout?

Answer 1

where high blood uric acid levels cause urate crystals to be deposited in the joint causing it to become inflamed

Question 2

How does gout present?

Answer 2

excruciating, acute, hot, swollen and painful joint (similar to septic arthritis!)

Question 3

What is the name given to subcutaneous uric acid deposits?

Answer 3

gouty tophi

Question 4

Name 3 sites where gouty tophi are commonly found in gout:

Answer 4

1) hands
2) elbows
3) ears

Question 5

Give 8 risk factors for gout:

Answer 5

1) male
2) alcohol consumption
3) family history
4) CVD
5) high purine diet (meat and seafood)
6) kidney disease
7) obesity
8) diuretics

Question 6

What three joints are most commonly affected by gout?

Answer 6

1) the base of the big toe (metatarsophalangeal joint)
2) the base of the thumb
3) wrist

Question 7

How is gout diagnosed?

Answer 7

clinically, supported by a raised serum urate level on blood test

Question 8

What joint aspiration finding would be in line with gout?

Answer 8

monosodium urate crystals

Question 9

Describe the composition, shape and properties of gout crystals: (3)

Answer 9

1) monosodium urate crystals
2) needle shaped
3) negatively birefringent of polarised light

Question 10

Give 4 x-ray findings associated with gout:

Answer 10

1) maintained joint space
2) lytic lesions in the bone
3) punched out erosions
4) sclerotic boarders with overhanging edges on erosions

Question 11

What is the first line drug for gout in acute episodes?

Answer 11

NSAIDs e.g. naproxen

Question 12

What drug is prescribed alongside long term NSAIDs?

Answer 12

PPI (for gastroprotection)

Question 13

What is the second line drug for gout pain relief in acute episodes?

Answer 13

colchicine

Question 14

What is the third line drug for gout pain relief in acute episodes?

Answer 14

oral steroids (e.g. prednisolone)

Question 15

What drug class is given for gout prophylaxis?

Answer 15

xanthine oxidase inhibitors

Question 16

Give two examples of xanthine oxidase inhibitors:

Answer 16

1) allopurinol
2) febuxotsat

Question 17

When is gout prophylaxis started?

Answer 17

after the first acute attack of gout

Question 18

What is pseudogout?

Answer 18

a crystal arthropathy caused by calcium pyrophosphate crystals collecting in the joints causing inflammation

Question 19

True or false: pseudogout typically presents less severely than gout

Answer 19

True

Question 20

Name 4 joints commonly affected by pseudogout:

Answer 20

1) knee
2) hip
3) shoulders
4) wrist

Question 21

How does pseudogout present? (2)

Answer 21

1) can be asymptomatic - an incidental X-ray finding
2) acute, stiff, hot, swollen joint

Question 22

What crystal is found in pseudogout joint aspiration?

Answer 22

calcium phosphate crystals

Question 23

What shape are calcium phosphate crystals?

Answer 23

rhomboid-shaped

Question 24

Describe the birefringent properties of calcium phosphate crystals:

Answer 24

positively birefringent of polarised light

Question 25

Give 5 X-ray findings associated with pseudogout:

Answer 25

1) chondrocalcinosis 2) loss of joint space 3) osteophytes 4) subarticular sclerosis 5) subchondral cysts

Question 26

Give 4 symptomatic relief treatments of pseudogout:

Answer 26

1) NSAIDs (naproxen) prescribed with a PPI for gastroprotection 2) colchicine 3) intra-articular steroid injections 4) oral steroids