Gout and pseudogout

Pathophysiology

Monosodium urate (MSU) crystals - needle shaped negative birefringence

Precipitants

1. purine-rich food
2. EtOH
3. trauma
4. chemo
5. diuretic use
6. RI

Clinical

1. Swelling, redness, warmth evolving RAPIDLY over <12 hours (to days)
2. First MTP (podagra) 60% > ankle > midfoot > knee > wrist
3. May have constitutional complaints

Diagnosis

1. Synovial fluid aspiration (above)

Note: serum uric acid levels unhelpful; ESR/CRP may be elevated

Treatment

Acute

1. Prednisone 50mg po qd for 3-4d and/or triamcinolone 60mg IM x1
2. Indomethacin 50mg po TID for 2d, tapered to 25mg po TID until flare is over OR Naproxen 500mg po bid x 3d and taper over 4-7d (Cr < 1.8mg/dL)
3. Colchicine 1.2mg po x 1 OR 0.6mg po qh x 3 or 1mg PO f/b 0.5mg q1h until relif, GI upset, or 8mg max
4. Intraarticular: Methylprednisolone acetate or triamcinolone 40-60mg x1 +/- Bupivicaine +/- Morphine 2-4mg
5. STOP thiazide diuretics

Chronic

1. Allopurinol for urate overexcretors
2. Probenecid for urate underexcretors

Source

H-N; EMP