Pseudogout

Question 1

What causes pseudogout?

Answer 1

Crystal arthropathy caused by calcium pyrophosphate crystals being deposited in the joints

Question 2

Presentation of pseudogout

Answer 2

Similar to gout

Typically an older adult with a hot, swollen, stiff and painful knee (or wrist or shoulder or hip)

Question 3

Pseudogout can be associated with

Answer 3

Haemochromatosis

Hyperparathyroidism

Low magnesium, low phosphate

Acromegaly

Wilson’s disease

Particularly expect an underlying risk factor in younger people (<60)

Question 4

Investigations in pseudogout

Answer 4

Joint aspiration:

• No bacterial growth
• Crystals are:
• Rhomboid
• Positively birefringent
• Calcium pyrophosphate crystals

Joint X-ray can show:

• Chondrocalcinosis is the classic x-ray change in pseudogout. I
• It appears as a thin white line in the middle of the joint space caused by the calcium deposition.
• May also see the LOSS features as in osteoarthritis

Question 5

Management of pseudogout

Answer 5

Joint aspiration for diagnosis and to exclude septic arthritis

NSAIDs or steroid injections/ oral steroids or colchicine can be used for symptom management

Symptoms usually resolve spontaneously over several weeks

If severe - joint washout is an option