Crystal Arthropathies

Question 1

Gout is a disorder of what metabolism

Answer 1

Uric acid metabolism

Question 2

What causes gout

Answer 2

Deposition of mono sodium rate crystals in soft tissues due to disordered uric acid metabolism

Question 3

What triggers a gout attack

Answer 3

Uncoated mono sodium rate crystals or sudden large change in crystal concentration

Question 4

Are monosodium irate crystals inert or active when coated with serum proteins

Answer 4

Inert

Question 5

Cycle of gout attack

Answer 5

Attack starts -> crystals form -> WBC attack -> cell popped by crystals -> proteins released -> further inflammation + pain -> proteins decr pH allowing more crystals to form

Question 6

Is gout usually mono or polyarticular

Answer 6

Monoarticular

Question 7

Podagra

Answer 7

Gout affecting 1st MTP joint in big toe

Question 8

Most common joints effected by gout

Answer 8

1st MTP
other small lower extremity joints

Question 9

How does a gout attack begin

Answer 9

Suddenly
Max intensity in 8-12hrs

Question 10

Are men or women affected by gout more

Answer 10

Men

Question 11

Characteristics of gout affected joint

Answer 11

Red
Hot
Exquisitely tender
Pain starts acutely usually at night

Question 12

Why do untreated 1st attacks resolve spontaneously in less than 2 weeks

Answer 12

Crystals get coated by serum proteins or phagocytosed

Question 13

How does gout progress over time

Answer 13

Attacks get closer,more painful, and last longer
Attacks eventually become continuous
Becomes polyarticular
Can affect other synovial structures

Question 14

Gouty tophi

Answer 14

Nodular masses of monosodium urate crystals in soft tissues

Question 15

What cells surround ms urate crystals in tophi

Answer 15

Lymphocytes
Macrophages
Foreign body giant cells

Question 16

Uric acid is an end stage by product of which metabolism

Answer 16

Purine metabolism

Question 17

How is Uric acid removed

Answer 17

Urine
Faeces

Question 18

What serum urate level is saturation

Answer 18

6.8mg/dL

Question 19

What is high serum urate called

Answer 19

Hyperuricemia

Question 20

Gout risk factors

Answer 20

Foods high in purines
Under excretion of Uric acid - renal insufficiency, dehydration, diuretics

Question 21

How many characteristics on the gout criteria are needed for a probable gout diagnosis

Answer 21

6+

Question 22

What is needed for a definitive gout diagnosis

Answer 22

Urate crystals in joint fluid during attack and joint fluid culture negative for organisms during attack

Question 23

Gout synovial fluid characteristics

Answer 23

Inflammatory
High WBCs
Polymorphonuclear neutrophils
Urate crystals

Question 24

What level of hyperuricemia requires treatment

Answer 24

11mg/dL+

Question 25

How does gout effect joint space

Answer 25

No effect

Question 26

Gout characteristics on XR and ultrasound

Answer 26

Soft tissue swelling Incr blood flow Erosion outside joint capsule Rate bite erosions

Question 27

What imaging type can detect and measure Uric acid crystals

Answer 27

Dual energy computed tomography DECT

Question 28

How can tophi lead to bone erosion

Answer 28

Produce pro inflammatory cytokines which stimulate osteoclasts via RANKL

Question 29

Acute gout attack treatment

Answer 29

NSAIDS Colchicine - used less now Corticosteroids IL1 biologicals - rilonacept canakinumab anakinra

Question 30

How long should NSAID dose be changed during and after a gout attack

Answer 30

High for 2-3 days Taper over 2 wks Keep taking until symptoms absent for 2 days

Question 31

Why is colchicine used less for gout now

Answer 31

Narrow therapeutic window Toxicity risk

Question 32

Colchicine MOA

Answer 32

Blocks mitosis by preventing Tubulin polymerisation decreasing neutrophil numbers

Question 33

Why is coffee mildly protective against gout

Answer 33

Increase urate excretion

Question 34

Chronic gout treatment

Answer 34

Decr Uric acid level Allopurinol Probenecid Rasburicase

Question 35

Allopurinol MOA

Answer 35

Inhibits Xanthine oxidase -> decr Uric acid generation

Question 36

Probenecid MOA

Answer 36

Incr uric acid excretion

Question 37

Rasburicase MOA

Answer 37

catalyses conversion of uric acid to allantoin

Question 38

What is calcium pyrophosphate deposition disease also known as

Answer 38

Pseudogout

Question 39

Calcium pyrophosphate deposition disease

Answer 39

Acute deposition of calcium pyrophosphate crystals in and around joints due to excess Ca and PO4

Question 40

Pseudogout/CPDD symptoms

Answer 40

Pseudo OA symptoms or asymptomatic

Question 41

Pseudogout/CPDD X-ray findings

Answer 41

Osteophytes Soft tissue calcification Chondrocalcinosis

Question 42

What causes joint inflammation in Pseudogout/CPPD

Answer 42

Release of CPDD crystals into joint space -> phagocytosis of crystals -> cytokine release -> inflammation

Question 43

What triggers acute Pseudogout/CPDD attacks

Answer 43

Trauma Rapid serum ca conc decr

Question 44

Gout crystal shape and charge

Answer 44

Negative charge Needle shape

Question 45

CPDD crystal charge and shape

Answer 45

Positive charge Rhomboid shape

Question 46

Pseudogout/CPDD treatment’s

Answer 46

Intra articular corticosteroids NSAIDs

Question 47

What condition can rarely have cholesterol and lipid crystals in the synovial fluid

Answer 47

RA