RheumatoidAthritisRecording

Introduction to Rheumatoid Arthritis

• Definition: Chronic systemic autoimmune inflammatory disease affecting synovial joints.

• Key Term: Synovitis - inflammation of the synovial membrane.

• Autoimmune Mechanism: Body's immune system mistakenly attacks its own cells.

Epidemiology and Risk Factors

• Demographics: Predominantly affects women, particularly those of older age.

• Risk Factors:

  • Smoking

  • Obesity

  • Female gender

  • Increasing age

  • Genetic predisposition and family history.

Clinical Presentation

• Symmetrical Joint Involvement: Primarily affects distal small joints (e.g., hands, wrists, feet).

• Common Deformities:

  • Ulnar Deviation: Rupture of collateral ligaments in MCP joints.

  • Swan Neck Deformity: Rupture of the palm and sole plate of PIP joints.

  • Boutonniere Deformity: Rupture of central extensor tendons.

• Possible Manifestations: Muscle wasting and tendon ruptures.

Pathogenesis

• Underlying Mechanism: Triggered in genetically susceptible individuals by exposure to unknown antigens.

• Cellular Activation:

  • Activation of CD4 T cells leads to release of inflammatory mediators and cytokines.

  • Prominent cytokines involved are Tumor Necrosis Factor (TNF) and Interleukin-1 (IL-1).

• Progressive Damage: Results in joint destruction through mechanisms such as osteoclast activation.

Importance of Synovial Membrane

• Normal Function: Synovium is thin (1-3mm), acting as a barrier and nutrient source for cartilage.

• Thickening in RA: Can expand to 8-10mm leading to synovitis and cartilage destruction.

Diagnosis of Rheumatoid Arthritis

• Criteria for Diagnosis: Need to meet 4 out of 7 criteria:

  • Morning stiffness lasting at least 1 hour for 6 weeks.

  • Soft tissue swelling for at least 6 weeks.

  • Swelling in specific joints (PIP, MCP, wrist).

  • Symmetrical joint swelling for 6 weeks.

  • Presence of subcutaneous nodules.

  • Positive rheumatoid factor or anti-CCP antibodies.

  • Radiographic features of RA.

Treatment Options

• Early Treatment Goals: Focus on improving quality of life and achieving remission.

• First-line Treatment: DMARDs (Disease-Modifying Antirheumatic Drugs) are essential for RA management.

  • Methotrexate: Preferred DMARD, requires monitoring due to potential side effects such as hepatotoxicity.

  • Other DMARDs:

    • Leflunomide: Inhibits pyrimidine synthesis; requires loading dose.

    • Sulfasalazine: Effective with significant anti-inflammatory and antimicrobial effects.

    • Hydroxychloroquine (Plaquenil): Often used in combination; regular eye exams needed due to potential toxicity.

• Biologic DMARDs:

  • TNF Inhibitors: For patients unresponsive to DMARDs, include Enbrel, Humira, and Remicade.

  • Nontumor Necrosis Factor Inhibitors: Such as Rituxan (depletes B cells) mean targeting different mechanisms in the inflammatory pathway.

Treatment Algorithm Overview

• Initial Approach: Start treatment with DMARD upon diagnosis.

• Monitoring: Necessary for treatment efficacy and side effects; adjust based on patient response and disease activity.

Additional Considerations

• Potential Complications: Increased risk for cardiovascular events, other systemic manifestations, and possible increased cancer risk in RA patients.

• Non-Pharmacological Treatments: Include physical therapy and lifestyle adjustments.

Conclusion

• Importance of Education: Understanding the pathophysiology of RA is crucial for effective treatment and patient outcomes.

• Ongoing research is crucial for developing newer therapies and improving patient care.