What are the steps to diagnose and treat rheumatoid arthritis?

Diagnosis and Treatment of Rheumatoid Arthritis

Early referral to a specialist for suspected rheumatoid arthritis is essential for prompt diagnosis and treatment to prevent joint damage and disability.

Diagnosis of Rheumatoid Arthritis

Clinical Presentation

• Persistent synovitis (joint swelling) that cannot be explained by another disease
• Small joints of hands or feet are commonly affected
• Multiple joint involvement (symmetric polyarthritis)
• Morning stiffness lasting more than 30 minutes

When to Refer for Specialist Opinion

Refer urgently for specialist assessment if a patient has:

• Small joint involvement of hands or feet
• More than one joint affected
• Symptoms persisting for 3 months or longer 1

Laboratory Tests

1. Essential laboratory tests:

   • Rheumatoid Factor (RF) - sensitivity 69-84%, specificity 78-85% 2
   • Anti-Citrullinated Protein Antibodies (ACPA)/Anti-CCP - sensitivity 67-78.5%, specificity 95-98% 2
   • Erythrocyte Sedimentation Rate (ESR)
   • C-Reactive Protein (CRP)
   • Complete blood count with differential
   • Renal and hepatic function tests 3

2. Testing approach:

   • Test for RF in all patients with suspected RA who have synovitis 1
   • Consider anti-CCP testing if RF is negative and combination therapy is being considered 1
   • Anti-CCP has the highest specificity for RA diagnosis 2

Imaging

• Plain radiographs - baseline assessment
• Ultrasound - detects synovitis
• MRI - more sensitive for early erosions and synovitis 2

Diagnostic Criteria

According to the 2010 ACR/EULAR criteria, a score of ≥6 indicates definite RA 2

Treatment Approach

Treatment Goals

• Achieve remission (SDAI ≤3.3) or at minimum low disease activity (SDAI ≤11) 2
• Prevent joint damage and disability
• Maintain work and personal activities 4

First-Line Treatment

• Methotrexate is the preferred first-line DMARD 2, 4
  • Starting dose: 7.5-15mg weekly
  • Escalate to 20-25mg weekly as needed
  • Subcutaneous administration preferred over oral due to better bioavailability 2
• Add short-term glucocorticoids as bridge therapy to rapidly control inflammation 2

Monitoring Disease Activity

• Use composite measures such as:
  • Disease Activity Score 28 (DAS28)
  • Simplified Disease Activity Index (SDAI)
  • Clinical Disease Activity Index (CDAI) 2
• Monitor monthly for patients with high/moderate disease activity
• Monitor every 6 months for patients in sustained low disease activity or remission 2

Treatment Adjustments

• Assess response at 3 months - should see at least 50% improvement
• Target should be reached by 6 months
• If inadequate response to methotrexate, add or switch to:
  • Other conventional DMARDs, or
  • Biologic agents (TNF inhibitors, abatacept, tocilizumab), or
  • Janus kinase inhibitors (JAKi) 2

Biologic Therapy

• Indicated after inadequate response to at least one DMARD
• Options include:
  • TNF inhibitors
  • Rituximab (for patients with inadequate response to TNF inhibitors) 5
  • Other biologics (abatacept, tocilizumab) 2
• Screen for hepatitis B, hepatitis C, and tuberculosis before starting biologic therapy 3

Adjunctive Therapies

• NSAIDs for symptomatic relief
• Local glucocorticoid injections for persistent joint inflammation 2

Long-Term Management

Treatment De-escalation

• Consider tapering therapy after sustained remission for ≥1 year
• Sustained drug-free remission possible in 15-25% of patients 2

Monitoring for Complications

• Cardiovascular risk assessment (RA increases risk by 50%)
• Screen for depression and other psychosocial factors
• Monitor for chronic kidney disease, hypothyroidism, and periodontitis
• Regular urinalysis for proteinuria 2

Pitfalls to Avoid

• Delaying referral to specialist for patients with persistent synovitis
• Failing to start DMARD therapy early in disease course
• Not adjusting therapy when treatment targets aren't met
• Overlooking screening for comorbidities and complications
• Neglecting to screen for infections before starting biologic therapy

By following this structured approach to diagnosis and treatment, rheumatoid arthritis can be effectively managed in up to 90% of patients, preventing irreversible joint damage and disability.