Gout (crystal arthropathy)

Question 1

Define gout

Answer 1

Disorder of uric acid metabolism causing recurrent bout of acute arthritis caused by deposition of monosodium urate crystals in joints, also soft tissues & kidneys

Question 2

Aetiology of gout

general + 2 types of causes

Answer 2

Main metabolic disturbance is hyperuricaemia

Increased urate intake or production

Decreased renal excretion

Question 3

Aetiology of gout - increased urate intake/production

3

Answer 3

Increased dietary intake

Increased nucleic acid turnover - e.g. lymphoma, leukaemia, psoriasis

Increased synthesis of urate - e.g. Lesch-Nyhan syndrome

Question 4

Aetiology of gout - decreased renal excretion

3

Answer 4

Idiopathic

Drugs (e.g. ciclosporin, alcohol, loop diuretics)

Renal dysfunction

Question 5

Epidemiology of gout

gender, rare, common group

Answer 5

10x more common in males
Very rare pre puberty & rare in pre menopausal women
More common in HIGHER social class

Question 6

Presenting symptoms & signs of gout - acute attack

7

Answer 6

Sudden excruciating monoarticular pain
Usually affects metatarsophalangeal joint of great toe (podagra)
Symptoms peak at 24 hrs
Resolve over 7-10 days
Can present w/ cellulitis, polyarticular or periarticular involvement
Attacks often recurrent
Symptom free between attacks

Question 7

Presenting symptoms & signs of gout - acute attack precipitating factors
(5)

Answer 7

trauma
infection
alcohol
starvation
introduction/withdrawal of hypouricaemic agents

Question 8

Presenting symptoms & signs of gout - intercritical gout

Answer 8

asymptomatic period between acute attacks

Question 9

Presenting symptoms & signs of gout - chronic tophaceous

3

Answer 9

Follow repeated acute attacks
Persistent low grade fever
Polyarticular pain w/ painful tophi (urate deposits)
Best seen on tendons & pinna of ear

Question 10

Presenting symptoms & signs of gout - urate urolithiasis

Answer 10

Renal calculi symptoms

Question 11

Investigations for gout

3 types

Answer 11

Synovial fluid aspirate
Bloods
AXR/KUB film

Question 12

Investigations for gout - synovial fluid aspirate

4

Answer 12

Monosodium urate crystals will be seen
Needle shaped
NEGATIVE birefringence under polarised light microscopy
Microscopy & culture to exclude septic arthritis

Question 13

Investigations for gout - bloods

4

Answer 13

FBC - raised WCC
U&Es
Raised urate
Raised ESR

Question 14

Investigations for gout - AXR/KUB

Answer 14

Uric acid renal stones may be seen