Gout + Pseudogout

Question 1

What is gout?

Answer 1

Deposition of monosodium urate crystals in joints, kidneys and soft tissue, leading to reccurent, acute attacks of arthritis.

Question 2

Outline the epidemiology of gout

Answer 2

More common in men
Women - post-menopause
Alcoholics
Higher social class

Question 3

Outline 4 risk factors for gout

Answer 3

IHD
HTN
Obesity
DM

Question 4

Outline the 3 main causes of gout and give examples of each.

Answer 4

INCREASED URIC ACID INTAKE
- Purine-rish foods e.g. shellfish, red meat

INCREASED URIC ACID PRODUCTION
- High turnover e.g. lymphoma, leukaemia, psoriasis, polycythaemia vera

DECREASED EXCRETION

• Renal dysfunction (+ dehydration)
• DRUGS

Question 5

Which drugs can precipitate gout?

Answer 5

CANT LEAP

Cyclosporine
Alcohol
Nicotinic acid
Thiazides
Loop diuretics
Ethambutol
Aspirin
Pyrimizamide

Question 6

Outline the pathophysiology of gout.

Answer 6

Deposition of monosodium urate crystals in joints
Neutrophil infiltration and phagocytosis
Leads to release of enzymes and oxygen free radicals
Causes inflammation

Question 7

How does an acute gouty attack present?

Answer 7

Sudden, excruciating mono-articular pain, most often in big toe metatarsophalangeal joint.

Erythema around joint, restricted movement, inability to bear weight + may have low-grade fever

Peaks at 24h and resolves within 7-10 days.

Question 8

What is the asymptomatic period between acute attacks called?

Answer 8

Intercritical gout

Question 9

List 4 factors that can predispose to an acute gouty attack

Answer 9

Infection
Trauma
Alcohol
Starvation

Question 10

How does chronic gout present?

Answer 10

Persistent low-grade fever

Polyarticular pain with painful tophi – can be seen on tendons and pinna of ear.

Yellow crystals can be seen through skin e.g. pinna of ear, hands, tendons.

Question 11

How would you investigate gout?

Answer 11

BLOODS - FBC, U+Es, may have raised uric acid but not necessarily, in acute gout

SYNOVIAL FLUID ASPIRATION - should see monosodium urate crystals that are needle-shaped and negatively birefringent under polarising light

AXR/KUB film - check for uric renal stones

Question 12

Which test is diagnositc for gout?

Answer 12

Synovial fluid aspiration

Should show monosodium urate crystals

• needle shaped
• negatively birefringent under polarising light

Question 13

What is the main differential for gout? How would you rule it out?

Answer 13

Septic arthritis

Microscopy + culture

Question 14

How would you manage gout?

Answer 14

NSAIDs (or Colchine if contra)

Intra-articular steroids

Intramuscular ACTH if necessary

Surgery if large/ulcerating tophus

Question 15

Preventative measures for gout

Answer 15

lifestyle modification, weight loss, alcohol abstinence, avoid dehydration

Question 16

2 prophylactic treatments for gout?

Answer 16

Allopurinol

Urosurics e.g. colchicine/probenecid/sulfinpyrazone

Question 17

Complicatons of gout?

Answer 17

Secondary infection/ulceration of tophi

Urate urolithiasis/nephropathy/renal failure

Question 18

What is pseudogout?

Answer 18

Deposition of CPPD crystals in the joints.

Question 19

What factors can predispose to pseuqdogout?

Answer 19

Hyperparathyroidism
Hypothyroidism
Hypophosphataemia
Haemochromatosis

Question 20

How does pseudogout present?

Answer 20

Painful, swollen joint - elbow, shoulder, knee

Chronic - stiff, functional impairment

Question 21

What investigations would you do for pseudogout?

Answer 21

BLOODS may show raised WCC and ESR
Culture - exclude infective arthritis

synovial fluid aspiration - weakly positive birefringent

Question 22

How would you manage psuedogout

Answer 22

NSAIDs, intra-articular steroids, colchicine if NSAIDs contra, methotrexate may be useful.