Acute Arthritis

77 yo female presented with a painful swollen red R wrist

Differentials:
- reactive arthritis (GI infection or URTI, also sexual but not likely at this age). So ask about any recent medications
- gout. Although more common in men, usually found in women with a background of OA. So ask abt OA. Can also be precipitated by thiazide diuretics (many old people take this). Also ask abt any Hx of gout.
- pseudogout
- septic arthritis. Especially if Px has been in hospital for quite some time; has an indwelling catheter. Most common bug staph Aureus (95%)
- fracture. Ask abt any Hx of trauma, falls
- Others: RA, psoriatic arthritis

Investigations:
- Aspirate joint to exlcude gout, pseudogout and septic arthritis (if clearly no trauma/fracture)
- Skin swab
- Urine culture
- XRay of wrist : presence of calcium chondrocalcinosis at joint support that Px has pseudogout