How do I diagnose and treat rheumatoid arthritis in an adult presenting with symmetric small‑joint polyarthritis and prolonged morning stiffness?

Diagnosis and Management of Rheumatoid Arthritis

Immediate Action: Urgent Rheumatology Referral

Refer this patient urgently to a rheumatologist within 6 weeks, even before serologic results return, because symmetric small-joint polyarthritis with prolonged morning stiffness is highly suggestive of rheumatoid arthritis, and early treatment within 3 months of symptom onset dramatically improves long-term outcomes including work disability, joint destruction, and mortality. 1, 2, 3

• Do not delay referral based on negative rheumatoid factor or normal inflammatory markers—these can be absent in early disease yet the patient still requires urgent specialist evaluation 1, 4
• The window for optimal intervention is narrow: 80% of patients remain employed at 2 years but only 68% at 5 years, and life expectancy is shortened by 3-5 years without aggressive early treatment 1

Diagnostic Workup

Clinical Assessment

Perform a systematic 28-joint examination documenting tender and swollen joints, focusing on the MCPs, PIPs, wrists, MTPs, and knees—the hallmark pattern is symmetric involvement of small joints with fusiform soft tissue swelling. 4, 3

• Morning stiffness lasting ≥1 hour (not just >30 minutes) is characteristic of RA and distinguishes it from mechanical arthritis 1
• Document functional impairment using the Health Assessment Questionnaire Disability Index 3
• Assess patient global disease activity on a visual analog scale 3

Serologic Testing

Order both rheumatoid factor (RF) and anti-citrullinated protein antibodies (ACPA/anti-CCP) simultaneously in every patient with synovitis—these are the diagnostic cornerstone. 3, 1

• ACPA has superior specificity (90%) with moderate sensitivity (60%), making it especially valuable for confirming RA 1, 3
• RF shows 60-80% sensitivity and ~70% specificity, rising to 80% in established disease 3
• High-positive results (>3× upper limit of normal) contribute 3 points to classification criteria; low-positive results contribute 2 points 3
• If RF is negative but clinical suspicion remains high, ACPA testing is essential before considering combination DMARD therapy 1, 3

Inflammatory Markers

Measure C-reactive protein (CRP) at baseline—it is preferred over ESR because it is more reliable, not age-dependent, and provides both diagnostic and prognostic information. 3

• Do not order both CRP and ESR simultaneously as this provides no additional clinical value 3
• An abnormal CRP or ESR adds 1 point to the 2010 ACR/EULAR classification score 3

Imaging Studies

Obtain plain radiographs of the hands, wrists, and feet at baseline—these are the initial imaging modality of choice. 3, 4

• Look for periarticular osteoporosis, soft tissue swelling, and marginal erosions 3
• The presence of erosions at baseline predicts persistent disease and contributes 5 points to classification criteria 3
• Repeat radiographs at 12 months to assess progression 3
• Consider ultrasound with power Doppler of the wrists and MCPs when clinical findings are equivocal—this can detect subclinical synovitis and active inflammation not apparent on examination 4, 3
• MRI of hands/wrists may be used when diagnosis remains uncertain, as it detects synovitis, bone marrow edema, and erosions invisible on plain films 3
• Avoid routine MRI or ultrasound for initial assessment—reserve these for diagnostically challenging cases 3

Additional Baseline Tests

• Obtain complete blood count, comprehensive metabolic panel (renal and hepatic function) before initiating DMARDs 5
• Do not order genetic testing or HLA-B27 routinely—HLA-B27 is only useful if spondyloarthropathy is suspected based on axial symptoms or enthesitis 1, 3
• Do not perform synovial biopsy routinely—reserve this for persistent monoarthritis when the differential diagnosis remains unclear (e.g., infection, malignancy) 1, 3

Classification Criteria (2010 ACR/EULAR)

A score ≥6 out of 10 classifies the patient as having definite RA, provided at least one joint has definite clinical synovitis not better explained by another disease. 1, 3

Scoring Components:

• Joint involvement (0-5 points): 1 large joint = 0 points; 2-10 large joints = 1 point; 1-3 small joints = 2 points; 4-10 small joints = 3 points; >10 joints with ≥1 small joint = 5 points 3
• Serology (0-3 points): Negative RF and ACPA = 0 points; low-positive RF or ACPA = 2 points; high-positive RF or ACPA = 3 points 3
• Acute-phase reactants (0-1 point): Normal CRP and ESR = 0 points; abnormal CRP or ESR = 1 point 3
• Symptom duration (0-1 point): <6 weeks = 0 points; ≥6 weeks = 1 point 3

Treatment Strategy

Treatment Goals and Monitoring

The treatment target is remission or low disease activity, assessed every 1-3 months using composite measures, with treatment adjustments made rapidly until the target is reached. 2

• This "treat-to-target" approach has transformed outcomes, with more patients maintaining employment and fewer requiring joint replacement surgery 1, 2
• Treatment decisions should be made through shared decision-making between patient and rheumatologist 2

First-Line Pharmacologic Management

Start methotrexate (MTX) 15 mg weekly as soon as the diagnosis is made, escalating to 20-25 mg weekly as tolerated—MTX should be part of the first treatment strategy in all patients with active RA. 2, 3

• Add folic acid 1 mg daily to reduce MTX toxicity 2
• Add low-to-moderate dose glucocorticoids (e.g., prednisone 5-10 mg daily) as initial short-term bridging therapy, then taper as rapidly as clinically feasible 2
• If MTX is contraindicated or not tolerated, use leflunomide or sulfasalazine as alternative first-line DMARDs 2

Escalation to Biologic Therapy

If the treatment target is not achieved with first DMARD strategy and poor prognostic factors are present (high disease activity, positive RF/ACPA, early erosions), add a biologic DMARD. 2

• TNF inhibitors (adalimumab, certolizumab, etanercept, golimumab, infliximab) are typically the first biologic agents used and should be combined with MTX 2
• If a first TNF inhibitor fails, switch to another TNF inhibitor, abatacept, rituximab, or tocilizumab 2
• Before initiating biologics, test for hepatitis B, hepatitis C, and tuberculosis 5

Refractory Disease

For severe refractory RA or when biologics are contraindicated, consider azathioprine, cyclosporine A, or in exceptional cases cyclophosphamide 2

De-escalation in Remission

• Consider tapering biologic DMARDs in patients achieving persistent remission, especially if combined with a synthetic DMARD 2
• In sustained long-term remission, cautious reduction of synthetic DMARD dosage may be considered 2

Non-Pharmacologic Management

Implement a multidisciplinary approach involving rheumatology nurses, physical therapists, occupational therapists, and when needed, psychologists. 2

• Provide patient education about disease pathophysiology, self-management skills, and joint protection principles 2
• Prescribe dynamic exercise programs incorporating both aerobic exercise and progressive resistance training—these improve fitness and strength without exacerbating disease activity 2
• Refer to occupational therapy for joint protection instruction and prescription of assistive devices, orthotics, and splints 2

Common Pitfalls to Avoid

• Never delay rheumatology referral waiting for positive serology—seronegative RA exists and early treatment is critical 1, 4
• Never use NSAIDs alone as initial therapy—they provide symptomatic relief but do not prevent joint destruction 6
• Never start DMARDs without baseline hepatic and renal function testing 5
• Never continue ineffective therapy for >3 months—adjust treatment aggressively to reach target 2
• Never abruptly stop glucocorticoids—taper gradually to avoid adrenal insufficiency 2