Gout and pseudogout

(Redirected from Gout)

Pathophysiology

  • Primarily an illness of middle-aged males and elderly adults
    • Gout in females usually occurs only after menopause
  • Gout is most common form of inflammatory joint disease in men >40yr
  • Presence of crystals does not exclude septic arthritis

Precipitants

Clinical Features

Gout affecting the first MP joint (podagra)
  • Joint pain may develop over period of hours
  • Primarily involves first MTP, knee, ankle

Differential Diagnosis

Monoarticular arthritis

Algorithm for Monoarticular arthralgia

Evaluation

  • Synovial fluid aspiration
    • Gout: yellow monosodium urate; negatively birefringent; needle-shaped
    • Pseudogout: calcium pyrophosphate; positively birefringent; rhomboid-shaped
  • Serum uric acid levels are not helpful (30% of patients with gout attack have normal levels)
    • Uric acid during attacks can be low due to the precipitation of gout crystals
    • High uric acid is >6.8
  • ESR may be elevated
  • no bacteria on Gram Stain
  • Pseudogout: XR of joint space may have radiolucent calcium pyrophosphate formation

Arthrocentesis of synoval fluid

Synovium Normal Noninflammatory Inflammatory Septic
Clarity Transparent Transparent Cloudy Cloudy
Color Clear Yellow Yellow Yellow
WBC <200 <200-2000 200-50,000

>1,100 (prosthetic joint)

>25,000; LR=2.9

>50,000; LR=7.7

>100,000; LR=28

PMN <25% <25% >50%

>64% (prosthetic joint)

>90%

Culture Neg Neg Neg >50% positive
Lactate <5.6 mmol/L <5.6 mmol/L <5.6 mmol/L >5.6 mmol/L
LDH <250 <250 <250 >250
Crystals None None Multiple or none None
  • Viscosity of synovial fluid may actually be decreased in inflammatory or infectious etiologies, as hyaluronic acid concentrations decrease
  • The presence of crystals does not rule out septic arthritis; however, the diagnosis is highly unlikely with synovial WBC < 50,000[1]

Management

Patients usually only require opioid and NSAID treatment in the ED with continued NSAID treatment as an oupatient. However any combination of the following treatments are acceptable[2]

NSAIDs

  • Do not give to patients with renal insufficiency (use opioids instead)
  • Substantial pain relief should occur within 2hr
  • Options:

Other options

Colchicine

  • Can be used as alternative agent to NSAIDs in patient with normal renal/hepatic function
  • 1.2mg PO (load), followed by 0.6mg one hour later x 1 [3]
  • May use to maximum of x3 doses, with more aggressive regimens totaling max dose up to 6mg[4]
  • Wait at least x3 days before starting another round of colchicine therapy
  • Renal impairment not absolute contraindication for acute flare but may consider dose reduction.
  • Dose adjustments for CYP3A4 inhibitors (HARRT, Calcium Channel Blockers, fluconazole, erythromycin, clarithromycin)
  • Colchicine should not be administered intravenously

Initial: 0.6-1.2mg, followed by 0.6 every 1-2 hours; some clinicians recommend a maximum of 3 doses; more aggressive approaches have recommended a maximum dose of up to 6mg. Wait at least 3 days before initiating another course of therapy

Steroids

  • Prednisone 30 to 50mg initially, and gradually tapered over 10 days, results in clinical resolution without rebound pain or complications[5][6]

Glucocorticoid injection

  • Even if gout has been diagnosed in the past, be cautious with glucocorticoid joint injection if the current clinical picture is uncertain since a septic joint can coexist with gout and a steroid injection would then worsen the patient's clinical status.

All patients

  • Hold diuretics
  • Consider starting losartan to replace diuretic (has modest uricosuric effect)
  • Alcohol and dietary counseling
  • Continue uric acid-lowering agents if already on prophylactic regimen (do not start)
  • Follow up with Primary Doctor or Rheumatology if having continued flares

Disposition

  • Generally outpatient treatment

See Also

References

  1. Shah K, Spear J, Nathanson LA, Mccauley J, Edlow JA. Does the presence of crystal arthritis rule out septic arthritis?. J Emerg Med. 2007;32(1):23-6.
  2. Khanna D. et al. 2012 American College of Rheumatology guidelines for management of gout. Part 2: Therapy and antiinflammatory prophylaxis of acute gouty arthritis. Arthritis Care Res. Oct 2012;64(10):1447-61
  3. Terkeltaub RA et al. High versus low dosing of oral colchicine for early acute gout flare: Twenty-four-hour outcome of the first multicenter, randomized, double-blind, placebo-controlled, parallel-group, dose-comparison colchicine study. Arthritis Rheum. 2010;62(4):1060.
  4. GlobalRPH. http://www.globalrph.com/gout.htm*colchicine
  5. Groff GD et al. Systemic steroid therapy for acute gout: a clinical trial and review of the literature. Semin Arthritis Rheum. 1990;19(6):329
  6. Janssens H. et al. Use of oral prednisolone or naproxen for the treatment of gout arthritis: a double-blind, randomised equivalence trial. Lancet. 2008;371(9627):1854.