What is the initial workup for rheumatoid arthritis?

From the Guidelines

The initial workup for rheumatoid arthritis should include a referral to a rheumatologist within 6 weeks after the onset of symptoms, clinical examination, and consideration of risk factors for persistent and/or erosive disease, including number of swollen joints, acute phase reactants, rheumatoid factor, ACPA, and imaging findings 1. The initial evaluation should focus on joint symptoms, duration, pattern of involvement, morning stiffness, and functional limitations.

• Laboratory testing should include:
  • Rheumatoid factor (RF)
  • Anti-citrullinated protein antibodies (ACPA/anti-CCP)
  • Erythrocyte sedimentation rate (ESR)
  • C-reactive protein (CRP)
  • Complete blood count (CBC)
• Imaging studies should include plain radiographs of affected joints to evaluate for erosions, joint space narrowing, or other structural changes.
• Ultrasound or MRI may be considered for early disease detection when conventional radiographs appear normal 1. The main goal of the initial workup is to establish the diagnosis, assess disease activity, and identify patients at risk of persistent arthritis, who should be started on DMARDs as early as possible, ideally within 3 months 1. Additional laboratory tests such as antinuclear antibodies (ANA), liver and kidney function tests, and hepatitis serology may be appropriate before initiating treatment. Early diagnosis is crucial as prompt treatment within the "window of opportunity" (first few months of symptoms) can significantly improve outcomes and potentially prevent irreversible joint damage. The 2017 EULAR recommendations 1 provide a comprehensive framework for the initial workup and management of rheumatoid arthritis, emphasizing the importance of early referral to a rheumatologist, clinical examination, and consideration of risk factors for persistent and/or erosive disease.

From the Research

Initial Workup for Rheumatoid Arthritis

The initial workup for rheumatoid arthritis involves several steps to diagnose and assess the disease. Some key components include:

• Clinical evaluation: assessing signs and symptoms such as joint swelling and tenderness, morning stiffness, and fatigue 2
• Laboratory tests:
  • Rheumatoid factor or anti-citrullinated protein antibody 3
  • C-reactive protein level or erythrocyte sedimentation rate 3, 2
  • Complete blood count with differential and assessment of renal and hepatic function 3
• Imaging studies:
  • Plain film radiography to assess the extent of anatomic changes in rheumatoid arthritis patients 2
  • Ultrasonography to study joint, tendon, and bursal involvement in RA 2
  • Other imaging techniques such as magnetic resonance, computed tomography, and scintigraphy may provide useful information about both the features and the extent of anatomic damage in selected rheumatoid arthritis patients 2

Disease Activity Assessment

Disease activity in rheumatoid arthritis can be evaluated using various measures, including:

• Signs and symptoms: counts of tender and swollen joints, morning stiffness, and patient-reported pain and global assessment of disease activity 4
• Laboratory measures: acute phase response, which is a direct reflection of the underlying inflammatory activity 4
• Composite indices: to assess disease activity or a disease activity state at any point in time and inform the physician (and patient) about improvement (or deterioration) in disease activity 4

Laboratory Evaluation

Initial laboratory evaluation should include:

• Complete blood count with differential and assessment of renal and hepatic function 3
• Patients taking biologic agents should be tested for hepatitis B, hepatitis C, and tuberculosis 3