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Rheumatoid Arthritis Management_Spring2025-

Overview of Rheumatoid Arthritis (RA)

Introduction to Rheumatoid Arthritis (RA)

  • RA is a systemic autoimmune inflammatory disease.

  • It is characterized by symmetric and chronic destructive synovitis, which is the inflammation of the synovial membrane lining joints.

Objectives

  • Define RA: Understand the nature of RA and its systemic effects.

  • Epidemiology and Risk Factors: Discuss prevalence and contributing factors.

  • Pathogenesis: Identify how RA develops in the body.

  • Clinical Presentation: Review signs and symptoms associated with RA.

  • Diagnostic Criteria: Understand the necessary criteria for RA diagnosis.

  • Treatment Algorithm: Examine pharmacologic and non-pharmacologic treatment methods.

Clinical Features of RA

Common Joint Involvement

  • Typically affects small joints: proximal interphalangeal, metacarpophalangeal joints, wrists, and ankles.

  • More significant affectation of:

    • Proximal interphalangeal and metatarsophalangeal joints.

    • Cervical spine joints.

  • Hips are less commonly involved.

Hand Deformities Associated with RA

  • Ulnar deviation: due to collateral ligament rupture at MCP joints.

  • Swan neck deformity: caused by rupture of the volar plate at PIP joints.

  • Boutonnière deformity: due to rupture of the central extensor of fingers.

  • Additional symptoms may include muscle wasting and tendon rupture.

Pathogenesis

  • RA is believed to be triggered by an autoimmune response, typically involving exposure to unknown arthritogenic antigens in genetically predisposed individuals.

  • Key processes:

    • Activation of CD4+ T cells and production of inflammatory mediators leading to joint destruction.

    • Cytokines like TNF and IL-1 stimulate inflammatory processes damaging synovial tissues and bone.

Role of Cytokines

  • Cytokines (e.g., TNF, IL-1):

    • Produced by macrophages and activated synovial lining.

    • Lead to joint damage by promoting inflammation and activating osteoclasts.

Formation of Pannus

  • Hyperplastic synovium rich in inflammatory cells invades joint surfaces, leading to cartilage destruction and bone erosion.

  • Release of IL-1 and growth factors from the pannus promotes joint degeneration.

Diagnostic Criteria for RA

ACR/EULAR Criteria

  • Individuals must meet four of the seven criteria:

    • Morning stiffness for at least one hour for six weeks.

    • Soft tissue swelling (arthritis) in three or more joints for at least six weeks.

    • Swelling in specific joints (e.g., proximal interphalangeal) for six weeks.

    • Symmetrical joint involvement for six weeks.

    • Presence of subcutaneous nodules.

    • Positive test for rheumatoid factor.

    • Radiographic features showing erosion or periarticular osteopenia in hand/wrist joints.

Treatment Approaches

Treatment Algorithm for RA

  1. Early RA: Less than 6 months of symptoms.

  2. Established RA: Symptoms present for at least 6 months.

Pharmacologic Therapies

  • DMARDs (Disease-Modifying Antirheumatic Drugs): Methotrexate is the preferred first-line treatment due to its rapid onset.

  • Biologics: TNF inhibitors (Etanercept, Infliximab etc.) are administered for moderately to severely active RA.

  • Glucocorticoids: Used as adjunct therapy to manage inflammation.

Other Treatment Methods

  • Physical Therapies: Exercise and physiotherapy are essential for joint function.

  • Dietary Interventions: Nutritional support can help manage symptoms.

Monitoring and Follow-up

  • Regularly monitor disease activity using validated tools such as the Disease Activity Scale (DAS).

  • Assess and manage potential adverse effects of treatments, particularly for DMARDs and biologics.