What is the initial workup and treatment approach for a patient presenting with inflammatory arthritis?

Workup for Inflammatory Arthritis

Initial Clinical Assessment

Patients presenting with joint swelling associated with pain or stiffness affecting more than one joint should be referred to a rheumatologist within 6 weeks of symptom onset, as early diagnosis and treatment significantly impacts long-term outcomes. 1

Key Clinical Features to Identify

• Joint examination: Assess for synovitis (joint swelling, tenderness, warmth) using systematic palpation of all peripheral joints, particularly metacarpophalangeal, proximal interphalangeal, wrist, and metatarsophalangeal joints 1
• Morning stiffness: Duration >30-60 minutes that improves with activity is highly suggestive of inflammatory arthritis 1, 2
• Pattern recognition: Symmetric polyarticular involvement is most common, though monoarticular or oligoarticular presentations occur in 25% of cases 2
• Joint count: Perform 28-joint count including proximal interphalangeal joints (1st-5th), metacarpophalangeal joints (1st-5th), wrists, elbows, shoulders, and knees bilaterally 1

Essential Laboratory Workup

Mandatory Initial Tests

The following laboratory panel must be obtained at initial presentation: 1

• Complete blood count - to assess for anemia of chronic disease and exclude hematologic disorders 1
• Erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) - elevated acute phase reactants support inflammatory process 1
• Rheumatoid factor (RF) - positive in 70-80% of RA patients 1
• Anti-cyclic citrullinated peptide (anti-CCP) antibodies - highly specific for RA and predicts erosive disease 1
• Antinuclear antibodies (ANA) - to exclude other connective tissue diseases 1
• Liver transaminases - baseline assessment before initiating disease-modifying therapy 1
• Renal function and urinalysis - baseline assessment and to exclude renal involvement 1

Prognostic Assessment

Once inflammatory arthritis is confirmed, assess the following factors that predict persistent and erosive disease: 1

• Number of swollen and tender joints (higher counts = worse prognosis) 1
• Elevated ESR or CRP levels 1
• Positive RF and/or anti-CCP antibodies (especially high titers) 1
• Presence of radiographic erosions on baseline imaging 1

Imaging Studies

Initial Radiographic Evaluation

• Plain radiographs of hands and feet - obtain baseline films to assess for erosions and periarticular osteoporosis 1
• Ultrasound with power Doppler - may be used when clinical examination is equivocal to confirm synovitis, as it is more sensitive than clinical examination alone 1
• MRI - reserved for doubtful cases or when ultrasound is unavailable, can detect early synovitis and bone edema not visible on plain films 1

Additional Imaging Considerations

• Synovial fluid analysis - should be obtained whenever possible, particularly in monoarticular presentations to exclude septic arthritis or crystal arthropathy 1
• Chest radiograph - consider if pulmonary symptoms present or before initiating biologic therapy 1

Disease Activity Measurement

Quantitative disease activity assessment using composite measures is essential for treatment decisions: 1

• Simplified Disease Activity Index (SDAI) or Clinical Disease Activity Index (CDAI) - preferred in clinical practice as they don't require complex calculations 1
• Components to measure: tender joint count (28 joints), swollen joint count (28 joints), patient global assessment (0-100mm VAS), physician global assessment (0-100mm VAS), and CRP (for SDAI) 1
• Target: Clinical remission (SDAI ≤3.3 or CDAI ≤2.8) 1

Critical Pitfalls to Avoid

• Delaying referral: Waiting beyond 6 weeks to refer patients with polyarticular synovitis significantly worsens outcomes 1
• Relying solely on serology: RF and anti-CCP can be negative in 20-30% of RA patients; diagnosis is primarily clinical 1, 3
• Missing extra-articular manifestations: Assess for rheumatoid nodules, pulmonary involvement, ocular symptoms, and vasculitis 3, 2
• Inadequate baseline assessment: Failure to obtain complete laboratory panel delays treatment initiation and prevents monitoring for drug toxicity 1
• Ignoring functional assessment: Document baseline functional status using Health Assessment Questionnaire (HAQ) for longitudinal comparison 1

Initial Treatment Approach

Immediate Symptomatic Management

NSAIDs should be initiated after evaluating gastrointestinal, renal, and cardiovascular risks, using the minimum effective dose for the shortest duration possible. 1, 4

• Intra-articular glucocorticoid injections - highly effective for oligoarticular involvement providing relief for up to 4 months 1, 5
• Systemic glucocorticoids (prednisone 10-20 mg/day) - may be used as temporary adjunctive therapy to reduce pain and swelling while awaiting DMARD effect 1

Disease-Modifying Therapy

Patients at risk of persistent or erosive disease should be started on disease-modifying antirheumatic drugs (DMARDs) as early as possible, even if they don't yet fulfill classification criteria. 1

• Methotrexate is the anchor drug and should be initiated first in patients at risk of persistent disease, typically starting at 7.5-15 mg weekly orally 1, 6
• Treatment target: Achieve clinical remission or lowest disease activity possible 1
• Monitoring frequency: Assess disease activity every 1-3 months until remission achieved 1

When to Escalate Therapy

• If inadequate response after 3 months of methotrexate monotherapy: Add biologic DMARD (TNF inhibitor, IL-6 receptor inhibitor, or T-cell costimulation blocker) 1
• For severe disease with poor prognostic features: Consider combination therapy with methotrexate plus biologic agent from onset 1

Monitoring Strategy

Regular monitoring must include: 1

• Clinical assessment: Tender/swollen joint counts, patient and physician global assessments every 1-3 months 1
• Laboratory monitoring: ESR, CRP at each visit; complete blood count and liver function tests every 4-8 weeks on methotrexate 1, 6
• Radiographic monitoring: Repeat hand and foot radiographs every 6-12 months during first few years 1
• Functional assessment: HAQ or similar patient-reported outcome measure 1

Non-Pharmacologic Interventions

• Dynamic exercises and progressive resistance training - improve fitness, strength, and are safe in active disease 1
• Occupational therapy - for joint protection techniques, assistive devices, and splinting 1
• Patient education - regarding disease pathophysiology, self-management, and treatment expectations 1
• Lifestyle modifications: Smoking cessation (strongly associated with disease progression), dental care, weight control, and vaccination status review 1