Gout

Question 1

What is gout?

Answer 1

Common inflammatory arthropathy characterised by painful and swollen joints

Question 2

Epidemiology

Answer 2

Males
30-60
Increases with age

Question 3

Aetiology

Answer 3

Hyperuricaemia is necessary for gout to occur BUT not all patients with hyperuricaemia will develop gout

1. Inherited error of metabolism of purine synthesis/renal excretion of uric acid
2. Disorders that increase UA production (myeloproliferative) or disorders that reduce UA secretion (chronic renal failure)

Question 4

Risk factors

Answer 4

Renal disease
High cell turnover (psoriasis, leukaemia, lymphoma)
Alcohol consumption
High fructose, meat, seafood
Obesity
Medications; chemo, diuretics, cyclosporin

Question 5

Pathophysiology

Answer 5

Disorder of purine metabolism –> hypeuricaemia
Prolonged hyperuricaemia –> deposition of urate crystals in joints/tissues/tendons
- Crystals trigger inflammatory response (e.g. TNFalpha)
- Temp and pH of synovium may have an impact?

Question 6

What are the clinical stages of gout

Answer 6

1. Acute gouty arthritis
   - Monoarthritis: 1st MTP joint, knee, ankle, wrist
   - Rapid clinical onset, low grade fever, leucocytosis
2. Chronic tophaceous gout
   - After repeated attacks –> rate crystals deposited in bone, joints and cartilage
   - Form a nodule = TOPHI that resorbs and erodes bone

Question 7

What is the typical history

Answer 7

• Monoarticular in first attack
• Rapid onset severe pain
• may be after beer or fatty foods
• Erythema, decreased ROM, warmth
• Nocturnal mostly!!!!
• Joint stiffness

Question 8

Podagra

Answer 8

MTP of big toe

Question 9

Gonagra

Answer 9

Knee

Question 10

Chiragra

Answer 10

joints of thumb

Question 11

What are the features on Ex

Answer 11

Severe pain with redness, swelling, tenderness, heart
Progressive joint destruction
Tophi formation (painless, hard nodules on the extensor surfaces/dorsal of hands, feet, helix of ears) Look white and chalky

Question 12

What Ix

Answer 12

Bloods:
- Serum increased uric acid
- leucocytosis and increased CRP/ESR in acute attacks

Arthrocentesis:
- Polarised light microscopy: needle shaped negatively bifringent rate crystals
- >2000 WCC
- Glucose lower than blood

Imaging:
- USS: double contour +/- tophi
- X-Ray = not useful in acute gout but for chronic you can see lytic lesions, radio-opaque soft tissues, joint space narrowing late

Question 13

DDx

Answer 13

pseudo gout/CPDD

Question 14

Mx of acute attack

Answer 14

High dose NSAIDs
Colchicine if NSAIDs contraindicated
Steroids intra-articular (not systemic)

Question 15

Mx of chronic/prophylaxis

Answer 15

Indicated if you have >1 attack per year, renal stones, tophi

• Allopurinol: xanthine oxidase inhibitor. Start 2 weeks post-attack

Question 16

Non-pharmacologic Mx:

Answer 16

Rest and elevate joint
Icepacks
Limit dietary red meat, seafood, alcohol, high fructose foods
Weight management

Question 17

Complications

Answer 17

Nephrolithiasis
Uric acid nephropathy
Joint destruction