Crystal Arthritis: Gout, Pseudogout

Question 1

Gout

• risk factors
• pathophysiology

Answer 1

High urate => urate crystal formation

Older males
Red meats, shellfish, alcohol
CKD

Thiazides, ACEi, ARBs (CCBs are protective)
Cytotoxics
-myelo/lymphoproliferative malignancies

Question 2

Gout

• presentation
• investigation, diagnosis
• management

Answer 2

Flares

• significant pain, swelling, red
• big toe, ankle, wrist, knee

DEFINITIVE - joint aspiration => -ve birefringent needles

Acute - NSAID + cont allopurinol if already using it

• colchicine if NSAID not an option
• CS if colchicine not an option

Maintenance - allopurinol
-2nd line febuxostat

Conservative

• reduce alcohol, red meat, shellfish
• weight loss

Question 3

Pseudogout

• risk factors
• pathophysiology
• presentation
• diagnosis, investigation

Answer 3

Deposition of calcium pyrophosphate crystals in joints

• increasing age
• high PTH (high Ca, low PO4)
• low Mg

Knee, wrist, shoulders

DEFINITIVE - joint aspiriation => positively birefringent rhomboid crystals

Acute - NSAID

• colchicine if NSAID not an option
• CS if colchicine not an option