Gout ☺️

Question 1

Formation of uric acid and pathophysiology

Answer 1

Purine metabolised by xanthine oxidase => urate crystals

Urate precipitates in joint => macrophages trigger inflammation

Question 2

Risk factors

Answer 2

Genetics, age, male, post menopausal
Overweight
Purine rich diet 
-red meat, sea food, alcohol
Thiazides, ACEi

Cytotoxics => tumour lysis

Question 3

Presentation

Answer 3

Rapid onset, single joint
Heat, pain, redness, swelling in big toe/knee
Affects small joints
Tophi on tendon surfaces - builds over years
Symptoms of renal calculi
With/without systemic symptoms like septic arthritis

Question 4

Diagnosis

Answer 4

Synovial fluid aspiration - negatively birefringent needle crystals under polarised light

Question 5

Management

• lifestyle
• acute medical
• preventative medical
• important SE of allopurinol

Answer 5

Lifestyle

• reduce red meat, seafood, alcohol consumption
• swap ACEi/thaizide - CCB can be protective

Medical - acute
FIRST LINE - NSAID 
Colchicine
Prednisolone
SECOND LINE - anakira, canakinumab (IL1)

Ongoing
-allopurinol or febuxostat => urate lowering agent (don’t stop in acute)

Allopurinol - risk of DRESS (new skin rash)

Question 6

Investigations

Answer 6

RULE OUT SEPTIC ARTHRITIS FIRST

• FBC => leukocytosis
• high CRP, ESR
• U&E => assess for any kidney damage from renal stones

DEFINTIVE - synovial fluid aspiration
-needle shaped negative birefringent monosodium urate crystals