GOUT

Question 1

What are the two main joints affected by gout?

Answer 1

• Base of great toe
• Knee

Question 2

A patient with long-standing gout presents with the following. Explain what this shows and what causes it. Do you expect this condition to be painful? Where else can it occur?

Answer 2

Tophi → chunks of uric acid (monosodium urate) crystals accumulate in and around joints as result of advanced gout.

• Usually not painful or tender
• Can occur in ears, tendons, bursa

Question 3

What type of kidney stone would you expect in somebody with gout?

Answer 3

Uric acid kidney stones

Question 4

Where can urate deposit in kidneys? What can this cause in people with gout?

Answer 4

Renal medulla + pyramids

→ Gout nephropathy

Question 5

Why can renal failure, volume depletion, diuretics all cause gout attacks?

Answer 5

All reduce GFR and reduce uric acid excretion further

Question 6

What are the three main sources of purines?

Answer 6

Ultimately: DNA breakdown

• ​Red meat
• Seafood
• Trauma/surgery (tissue breakdown)

Question 7

How does alcohol trigger gout? Two main points

Answer 7

• Metabolism consumes ATP → contains adenosine (purine) → converted into uric acid
• Lactic acid is produced in alcohol metabolism → activates urate transporter-1 in PCT (URAT1) → reabsorbs uric acid in exchange for anions such as lactate

Question 8

Why are people with myeloproliferative disorder is more likely to get gout?

Answer 8

High cell turnover → increased purine metabolism

Question 9

A male child with hypotonia, chorea, self-mutilation and gout has which syndrome?

Answer 9

Lesch-Nyhan Syndrome

Question 10

How do you diagnose gout?

Answer 10

Arthrocentesis with synovial fluid analysis

+ serum uric acid level

+ USS/XR

Question 11

What is an important DDx of acute gout and septic arthritis? How do you differentiate? What is the main prophylaxis?

Answer 11

Pseudogout AKA calcium pyrophosphate deposition disease (2/3 of patients with haemochromatosis have this condition)

• arthrocentesis differentiates between them
• colchicine preventative therapy

Question 12

Chondrocalcinosis is a key feature of which condition? What is it?

Answer 12

Calcium pyrophosphate deposition disease

Calcification of hyaline cartilage seen on x-ray → often asymptomatic

Question 13

What are the two main flares of pseudogout?

Answer 13

• Illness e.g. trauma, surgery
• Parathyroidectomy

Question 14

Chronic pseudogout mimics which other joint condition? How is it treated?

Answer 14

Osteoarthritis

→ treated the same way as OA in chronic disease