75% off all plans

Rheumatoid Arthritis

On this page

RA Basics - Joint Under Siege

  • Chronic, systemic autoimmune inflammatory disorder causing symmetrical, erosive polyarthritis.
  • Epidemiology: ~1% global (India ~0.75%); F:M 3:1; peak onset 30-50 yrs.
  • Risk Factors:
    • Genetic: HLA-DR4 (Shared Epitope), PTPN22.
    • Environmental: Smoking (major!), infections (P. gingivalis, EBV).
  • Pathogenesis:
    • T/B cell dysregulation → autoantibodies (RF, ACPA).
    • Key cytokines (TNF-α, IL-1, IL-6) drive synovitis, pannus formation, leading to cartilage & bone erosions. RA vs OA Joint Damage

⭐ Smoking is the most significant modifiable environmental risk factor for developing RA, especially seropositive RA (ACPA+).

RA Signs - The Body's Complaint

  • Articular (Joints):
    • Symmetrical polyarthritis (MCP, PIP, MTP, wrists). Spares DIPs.
    • Morning stiffness > 1 hour, eases with activity.
    • Pain, swelling, tenderness.
    • Late deformities: Swan neck, Boutonnière, ulnar deviation.
    • Atlantoaxial subluxation (C1-C2).
  • Extra-articular Manifestations:
    • Systemic: Fever, fatigue, weight loss.
    • Rheumatoid nodules (extensor surfaces).
    • Pulmonary: Pleurisy, nodules, ILD. Caplan syndrome (RA + pneumoconiosis).
    • Cardiac: Pericarditis, ↑CV risk.
    • Ocular: Scleritis, episcleritis, Sjogren's.
    • Heme: Anemia of chronic disease.
    • 📌 Felty's Syndrome: RA + Splenomegaly + Neutropenia.
    • Vasculitis (nail-fold infarcts).
    • Neuro: Carpal tunnel syndrome.

Late stage RA hand deformities

⭐ Felty's syndrome (RA, splenomegaly, neutropenia) is a classic triad associated with severe, long-standing RA and increased risk of infections.

RA Detective - Cracking the Case

  • 2010 ACR/EULAR Criteria: Score ≥ 6/10 for diagnosis.
    • Key domains:
      • Joints: Number & size (small > large).
      • Serology: RF, Anti-CCP (ACPA) levels.
      • Acute Phase Reactants: ESR, CRP.
      • Symptom Duration: ≥ 6 weeks.
  • Key Investigations:
    • Serology:
      • Rheumatoid Factor (RF): Positive in ~70-80%; not specific.
      • Anti-CCP (ACPA): Highly specific (~95%); often positive early.

        ⭐ Anti-CCP antibodies are more specific for RA than RF and may predict more severe, erosive disease.

    • Inflammatory Markers: ↑ ESR, ↑ CRP (correlate with disease activity).
    • Imaging:
      • X-rays (Hands & Feet): Periarticular osteopenia, joint space narrowing, marginal erosions (characteristic but late).
      • Ultrasound/MRI: Detect synovitis, early erosions.
    • Synovial Fluid Analysis: Inflammatory (WBC 2,000-50,000/µL, >50% PMNs, sterile, poor mucin clot).

RA Battle Plan - Taming the Flame

Goal: Remission or Low Disease Activity (LDA). Employ Treat-to-Target (T2T) strategy. Monitor disease activity (DAS28, CDAI) every 1-3 months.

  • Non-Pharmacological:

    • Patient education, physiotherapy, occupational therapy.
    • Lifestyle: Smoking cessation, weight management, joint protection.
  • Pharmacological:

    • Bridge Therapy: Glucocorticoids (low-dose, short-term, e.g., Prednisolone ≤10 mg/day), NSAIDs for symptom relief.
    • csDMARDs (Conventional Synthetic):
      • Methotrexate (MTX): Anchor drug. Start within 3 months of diagnosis. Dose: 7.5-25 mg/week. Folic acid supplementation (1-5 mg/day or 5 mg/week 24-48h post-MTX).
      • Alternatives/Adjuncts: Leflunomide (LEF), Sulfasalazine (SSZ), Hydroxychloroquine (HCQ - mild RA/combo).
    • bDMARDs (Biologic): If csDMARDs fail (inadequate response after 3-6 months of optimal therapy).
      • TNF-α inhibitors: Etanercept, Infliximab, Adalimumab.
      • Others: Rituximab (anti-CD20), Tocilizumab (anti-IL6R), Abatacept (CTLA4-Ig).
      • ⚠️ Screen for latent TB, HBV, HCV before initiating.
    • tsDMARDs (Targeted Synthetic - JAK inhibitors): Tofacitinib, Baricitinib, Upadacitinib. Oral. For csDMARD/bDMARD failure/intolerance.

⭐ Methotrexate (MTX) is the cornerstone DMARD; initiation within 3 months of RA diagnosis is crucial for better prognosis.

Rheumatoid Arthritis Treatment Algorithm

High‑Yield Points - ⚡ Biggest Takeaways

  • Symmetrical polyarthritis of small joints (MCP, PIP) with morning stiffness > 1 hour.
  • Key serology: Rheumatoid Factor (RF) and highly specific Anti-CCP antibodies.
  • Common extra-articular features: rheumatoid nodules, interstitial lung disease, vasculitis.
  • X-ray shows juxta-articular osteoporosis, erosions, and joint space narrowing.
  • Early DMARD (e.g., Methotrexate) therapy is crucial to prevent joint damage.
  • Felty's syndrome: RA triad of arthritis, splenomegaly, and neutropenia.
  • Caplan syndrome: RA with pneumoconiosis and intrapulmonary nodules.

Continue reading on OnCourse

Sign up for free to access the full lesson, plus unlimited questions, flashcards, AI-powered notes, and more.

CONTINUE READING — FREE

or get the app

Rezzy AI Tutor

Have doubts about this lesson?

Ask Rezzy, our AI tutor, to explain anything you didn't understand

Practice Questions: Rheumatoid Arthritis

Test your understanding with these related questions

A 30-year-old woman complains of bilateral pain and stiffness in the small joints of her hands, worse in the morning and improving throughout the day. What is the most likely diagnosis?

1 of 5

Flashcards: Rheumatoid Arthritis

1/10

_____ criteria is used for the diagnosis of Rheumatoid arthritis

TAP TO REVEAL ANSWER

_____ criteria is used for the diagnosis of Rheumatoid arthritis

EULAR

browseSpaceflip

Enjoying this lesson?

Get full access to all lessons, practice questions, and more.

START FOR FREE
Rezzy AI Tutor