What is the appropriate workup and management for a middle-aged to elderly male patient presenting with sudden onset joint pain suspected to be gout?

Gout Workup

For a middle-aged to elderly male with suspected acute gout, immediately perform joint aspiration with synovial fluid analysis for monosodium urate (MSU) crystals under polarized light microscopy—this is the gold standard diagnostic test with near 100% sensitivity and specificity when performed by experienced operators. 1

Initial Clinical Assessment

Key Diagnostic Features to Identify

• Rapid onset of severe pain reaching maximum intensity within 6-12 hours strongly suggests gout rather than other arthropathies 1
• First metatarsophalangeal joint involvement (podagra) is the classic presentation, though polyarticular involvement can occur, especially in patients with multiple comorbidities 2, 3
• Overlying erythema combined with rapid-onset severe pain is highly suggestive of gout 1
• History of recurrent attacks with similar presentation increases diagnostic probability 1

Critical Risk Factors to Document

• Diuretic use (thiazide or loop diuretics)—the most common iatrogenic cause with relative risk of 1.72 4, 1
• Obesity (relative risk 3.81), hypertension (relative risk 3.93), and chronic kidney disease (relative risk 4.95) 2, 1
• Alcohol consumption (especially beer and spirits) and diet high in meat, seafood, and high-fructose corn syrup 2, 4
• Medications including low-dose aspirin, cyclosporine, and tacrolimus 4, 1

Definitive Diagnostic Workup

Joint Aspiration (Gold Standard)

• Arthrocentesis with synovial fluid analysis is mandatory when septic arthritis cannot be clinically excluded, when the presentation is atypical, or for first suspected gout attack 1
• MSU crystals appear as needle-shaped, negatively birefringent crystals under polarizing microscopy with sensitivity and specificity approaching 100% 1
• Always perform Gram stain and culture even when MSU crystals are identified, as gout and septic arthritis can coexist 1

Laboratory Testing

• Serum uric acid level should be obtained immediately, though hyperuricemia alone does not diagnose gout and normal levels do not exclude it during an acute flare 1, 5
• Normal serum uric acid essentially rules out gout in the clinical context of recurrent monoarticular pain 1
• Inflammatory markers (ESR, CRP) and complete blood count to assess inflammation severity and rule out infection 1
• Renal function (creatinine, eGFR) to guide medication dosing and assess for chronic kidney disease 4, 1

Imaging Studies

When joint aspiration is not feasible or diagnosis remains uncertain:

• Ultrasound is the first-line imaging modality with the "double contour sign" on cartilage surfaces having 74% sensitivity and 88% specificity 1
• Always scan the first metatarsophalangeal joint bilaterally, even if asymptomatic, as this is the disease-specific target site 1
• Dual-Energy CT (DECT) has 85-100% sensitivity and 83-92% specificity for detecting MSU crystal deposits, but is more expensive and involves radiation exposure 1, 6
• Plain radiographs have limited value for diagnosing acute gout but can identify chronic changes and rule out other conditions 1

Acute Treatment (Initiate Immediately)

Choose one of the following anti-inflammatory agents 2:

First-Line Options

• Low-dose colchicine: 1.2 mg loading dose, then 0.6 mg one hour later (total 1.8 mg) 2, 4

  • Equally effective as high-dose with fewer adverse effects 2
  • Reduce to 0.5 mg daily or every other day if creatinine clearance 30-50 mL/min 4, 7

• Oral corticosteroids: Prednisolone 30-35 mg/day for 3-5 days 4

  • Preferred in patients with renal impairment or contraindications to NSAIDs 4

• NSAIDs: Full anti-inflammatory doses 2

  • Avoid in patients with significant renal impairment, cardiovascular disease, or gastrointestinal risk 4

Long-Term Management Considerations

When to Initiate Urate-Lowering Therapy (ULT)

• Do NOT initiate ULT after a first gout attack or in patients with infrequent attacks 2
• Initiate ULT in patients with:
  • Two or more gout flares per year 3
  • Presence of tophi 3
  • Radiographic evidence of gouty arthropathy 3
  • Multiple high-risk comorbidities (chronic kidney disease, hypertension, diabetes) 4

ULT Initiation Protocol (If Indicated)

• Start allopurinol at 100 mg daily, increasing by 100 mg every 2-4 weeks until serum uric acid <6 mg/dL 4, 8
• Target serum uric acid <6 mg/dL (360 μmol/L) for most patients; <5 mg/dL for patients with tophi 4, 3
• Mandatory flare prophylaxis for the first 6 months when starting ULT with colchicine 0.5-1 mg daily 4
• Never stop ULT during an acute flare—this perpetuates the cycle of recurrent attacks 4, 1

Lifestyle Modifications (Essential for All Patients)

• Weight loss if obese 4, 5
• Avoid alcohol, especially beer and spirits 4, 5
• Eliminate sugar-sweetened drinks and foods high in fructose 4, 5
• Reduce intake of red meat and seafood 4, 5
• Encourage low-fat dairy products, particularly skim milk 4
• Regular exercise to reduce mortality associated with hyperuricemia 4

Medication Adjustments

• If taking thiazide or loop diuretics, substitute if possible 4
• Switch to losartan (which has modest uricosuric effects) or calcium channel blockers for hypertension management 4
• Consider fenofibrate for hyperlipidemia, which has uricosuric properties 4

Common Pitfalls to Avoid

• Do not diagnose gout based on hyperuricemia alone—up to 80% of patients with hyperuricemia never develop gout 1
• Do not rely on serum uric acid to exclude gout during an acute flare—levels can be normal or even low during attacks 1, 5
• Do not stop aspirin in patients taking it for cardiovascular indications despite its mild uric acid-elevating effects 4
• Do not initiate ULT during an acute flare without concurrent anti-inflammatory prophylaxis—this will trigger mobilization flares 4
• Ultrasound sensitivity is significantly lower in early disease (<2 years) with only 50% sensitivity versus 63% in late disease 1