Gout

Elderly male patient with history of HTN, cardiovascular disease, and excess meat/pate/beer/high-fructose corn syrup consumption presents with painful first metatarsal joint swelling. Pain present x 1 day and reports similar, previous flares in the same joint. Denies fever, chills, trauma at affected site. Recently started on a diuretic for control of hypertension. Family history positive for gout. Unilateral first metatarsal joint inflammation and tophi noted on exam.

  • Obtain CBC, uric acid level

  • Diagnosis

    • Risk for gout ≥ 82.5% per Acute Gout Diagnosis Rule

    • Evaluation of joint aspirate with compensated polarized light microscopy shows negatively birefringent monosodium urate crystals

  • Treatment

    • Stop thiazide and/or loop diuretic and start losartan

    • Acute therapy

      • CrCl > 30: Indomethacin 50 mg TID

      • CrCl < 30: Colchicine 0.3 mg daily until flare resolves

      • Concern for pseudogout: Prednisone 40 mg x 4 days, then 20 mg x 4 days, then 10 mg x 4 days

    • Recurrent gout: Start allopurinol 100 mg qd s/p flare and increase by 100 mg (max 800 mg qd) every 2-4 weeks until serum urate < 6 mg/dL

  • Counseling

    • Pt advised to reduce consumption of meats, alcohol, and beverages sweetened with high-fructose corn syrup to reduce risk of gout flares

    • Pt encouraged to lose weight

Notes

  • Pathophysiology

    • Due to precipitation of monosodium urate crystals in joint space

    • Repeat flares can permanently damage joints leading to chronic pain

  • Risk factors

    • Age: Present in > 10% of patients > 80 years old

    • Loop and thiazide diuretics that increase uric acid levels

    • Purine-rich foods such as red meat, organ meats (liver), and shellfish

    • Two or more beer or spirit drinks per day; no increase risk with wine

    • Beverages sweetened with high-fructose corn syrup

  • Protective factors

    • Female sex: Hormones increase uric acid excretion (i.e. protective); gout is rare in premenopausal women

    • Losartan increases uric acid excretion

  • Diagnosis

    • Rule out trauma, infection and consider possibility of pseudogout

    • Diagnosis per American College of Rheumatology requires either

      • Identification of uric acid crystals in joint aspirate

      • Presence of ≥ 6 clinical, laboratory, or radiologic findings

  • Treatment

    • NSAIDs are first line; consider intra-articular injection to limit systemic absorption

    • Colchicine has no analgesic properties and has limited effect if started 72 to 96 hours s/p symptom onset

    • Patients of Korean, Chinese, or Thai descent are at higher risk for a severe skin hypersensitivity reaction when starting allopurinol

    • Stop thiazide diuretics and start losartan in their place as it lowers gout risk