Crystal induced arthritis

Question 1

3 main types of crystal induced arthritis

Answer 1

• gout
• calcium pyrophosphate dihydrate deposition disease
• basic calcium phosphate deposition disease

Question 2

Definition of gout

Answer 2

A form of arthritis caused by deposition of monosodium urate crystals within joints, associated with chronic hyperuricaemia

Question 3

At what concentration of urate is there risk of MSU crystal formation?

Answer 3

0.38 mmol/L

Question 4

Pro-inflammatory mediators that cause problems in gout

Answer 4

• IL- 1B
• TNF a
• IL-8

Question 5

Factors that influence uric acid production

Answer 5

• purine ingestion
• de-novo synthesis of purine in cells
• recycling
• degradation function of xanthine oxidase

Question 6

Which transporter is responsible for reabsorption of urate by kidneys?

Answer 6

URAT1

Question 7

Name for gout in big toe

Answer 7

Podagra

Question 8

Factors that might trigger acute gouty attacks

Answer 8

• alcohol
• meat and seafood
• fasting
• trauma
• surgery
• drugs

Question 9

What characterises chronic gout?

Answer 9

• destructive polyarticular involvement
• low-grade joint involvement
• joint deformity
• tophi

Question 10

Characteristics of gout under polraised microscopy

Answer 10

• strongly bifringent

- appear very bright

Question 11

Most common type of gout-related nephropathy

Answer 11

Kidney stones

Question 12

Treatment of acute gout attackes

Answer 12

• high dose NSAIDs
• colchicine (0.5mg 2-4 times a day)
• corticosteroids

Question 13

Treatment of hyperuricaemia

Answer 13

Uricostatic drugs (XO inhibitors - allopurinol)
Uricosuric drugs (URAT1 inhibitors - losartan, probenecid)
Uricolytic drugs (recombinant uricase - pegloticase)

Question 14

Prophylaxis for gout

Answer 14

• colchicine 0.5mg 2 times a day for 3-6 months

- low dose NSAIDs for 6-12 weeks

Question 15

Possible presentations of CPPD

Answer 15

• acute inflammatory arthritis (psuedogout)
• pseudo-OA
• OA-like presentation with discrete acute attacks
• pseudo-RA
• Psuedo-Charcot
• asymptomatic chondrocalcinosis on X-rays

Question 16

Where is chondrocalcinosis often found?

Answer 16

• knee
• wrist
• symphysis pubis

Question 17

Conditions associated with chondrocalcinosis

Answer 17

• hyperparathyroidism
• haemochromatosis
• hypophosphatasia
• hypomagnesemia
• gout, Wilson’s disease

Question 18

Diagnostic tests for CPPD

Answer 18

• CPPD crystals in synovial fliud
• plain radiograph
• U/S
• CT scan
• new MRI modalitis
• EM and X-ray diffraction

Question 19

What do CPPD crystals look like

Answer 19

positively bifringent rhomboid-shaped crystals

Question 20

Treatment of CPPD

Answer 20

• resting the joint
• NSAIDS
• intra-articular steroid injections
• colchicine (psuedogout)
• systemic corticosteroids
• hydroxychloroquine (chronic arthritis)

Question 21

Types of basic calcium phosphate crystals

Answer 21

• carbonate-substituted hydroxyapatite
• tricalcium phosphate
• otacalcium phosphate

Question 22

What is BCP deposition disease associated with?

Answer 22

• Milwaukee Shoulder syndrome
• OA
• calcific periarthritis, bursitis and tendinitis
• limited systemic sclerosis
• dermatomyositis
• mixed crystal deposition disease
• chronic renal failure
• hypercalcaemia

Question 23

Treatment of BCP arthropathy

Answer 23

• NSAIDs
• intra-articular steroid injection
• physiotherapy