Gout and Pseudogout

Question 1

What is Gout?

Answer 1

A crystal arthropathy associated with chronically high uric acid levels.

Question 2

What are gout tophi?

Answer 2

Subcutaneous deposits of uric acid, typically affecting small joints and connective tissue in hands, elbows and ears.

Question 3

How does gout present?

Answer 3

A single acutely hot, swollen and painful joint.

Question 4

What is an important differential of gout?

Answer 4

Septic arthritis

Question 5

Which joints are most commonly affected by gout?

Answer 5

• Metatarsophalangeal joint of the big toe
• Carpometacarpal joint (base of the thumb)
• Big joints e.g. knee and ankle

Question 6

What are the risk factors for gout?

Answer 6

• Male sex
• Obesity
• High purine diet e.g. meats and seafood
• Alcohol
• Diuretics
• CVS or Kidney disease
• Family history

Question 7

How is gout diagnosed?

Answer 7

• Clinically

- Aspiration of fluid from the joint (excluding septic arthritis)

Question 8

What will aspiration show in gout?

Answer 8

• No bacterial growth
• Needle shaped crystals
• negative birrefringente of polarised light
• Monosodium urate crystals

Question 9

What will an XR show in gout?

Answer 9

• Joint space is maintained
• Lytic lesions on the bone
• Punched out erosions
• Erosions can have sclerotic borders with overhanging edges

Question 10

How is acute gout managed?

Answer 10

• NSAIDs (first line)
• Colchicine (second line)
• Steroids (third line)

Question 11

When is colchicine used?

Answer 11

• Inappropriate for NSAIDs e.g. renal impairment, significant heart disease

Question 12

What is a notable side effect of colchicine and how is it fixed?

Answer 12

• GI upset (diarrhoea)

- Dose dependent so reducing dose should resolve

Question 13

What is the prophylactic treatment for gout?

Answer 13

Allopurinol

Question 14

How does allopurinol work?

Answer 14

Xanthine oxidate inhibitor, works by reducing the serum urate level

Question 15

What lifestyle changes protect from gout?

Answer 15

• Weight loss
• Hydration
• Minimise alcohol
• Reduce purine based foods e.g. meats and seafood

Question 16

What is pseudogout?

Answer 16

Crystal arthropathy, but with calcium pyrophosphate crystals

Question 17

What is pseudogout also called?

Answer 17

Chondrocalcinosis- calcium deposition in the joint

Question 18

How does pseudogout present?

Answer 18

• Older adult
• Hot, swollen and painful joint
• Typically affects the knee, but also shoulders, wrists and hips
• Can also be asymptomatic/incidental on XR

Question 19

How is pseudogout diagnosed?

Answer 19

• Exclude septic arthritis
• Tends to be milder than gout
• Definitive diagnosis is by aspirating synovial fluid

Question 20

What will aspiration show in pseudogout?

Answer 20

• Calcium pyrophosphate crystals
• Rhomboid crystals
• Positive birefringent of polarised light

Question 21

What will and XR show in pseudogout?

Answer 21

• Chondrocalcinosis (calcification of the chondral surface)
• Thin white line in the middle of the joint space
• LOSS (Same as OA)

Question 22

What is the pneumonic LOSS for a joint XR?

Answer 22

Loss of joint space
Osteophytes
Subarticular sclerosis
Subchondral cysts

Question 23

How is pseudogout managed?

Answer 23

• Asymptomatic cases need no treatment
• Symptoms themselves usually resolve over several weeks
• NSAIDs
• Colchicine
• Joint aspiration and steroid injection
• Oral steroids