Master Rheumatology
for MRCP Part 1

Core Concepts

Rheumatology is the specialty concerned with the diagnosis and management of musculoskeletal conditions, primarily encompassing autoimmune and inflammatory diseases affecting joints, muscles, soft tissues, and connective tissues, often with systemic involvement. Key themes include inflammation, autoimmunity, chronic pain, and progressive organ damage. Conditions range from common inflammatory arthritides (e.g., Rheumatoid Arthritis) to rare systemic vasculitides and connective tissue disorders (e.g., Systemic Lupus Erythematosus).

Clinical Presentation

• Joint Pain & Swelling: Differentiate inflammatory (morning stiffness >30 min, improves with activity, worse at rest, symmetrical) from mechanical (worse with activity, improves with rest, localised).
• Morning Stiffness: Classic for inflammatory arthritis (e.g., RA, AS, PsA).
• Fatigue & Malaise: Common systemic symptoms across most inflammatory rheumatic diseases.
• Specific Rashes: Malar rash (SLE), Gottron's papules/heliotrope rash (dermatomyositis), psoriatic plaques (psoriatic arthritis), livedo reticularis (vasculitis, APS).
• Raynaud's Phenomenon: Vasospasm of digital arteries, often associated with connective tissue diseases (scleroderma, SLE).
• Dry Eyes/Mouth (Sicca): Suggestive of Sjogren's syndrome.
• Muscle Weakness: Proximal muscle weakness can indicate inflammatory myositis (polymyositis, dermatomyositis).
• Systemic Symptoms: Fever, weight loss, lymphadenopathy (SLE, vasculitis, malignancy mimic).
• Ocular Symptoms: Red eye (uveitis in AS/PsA), blurred vision/amaurosis fugax (GCA).
• Neurological Symptoms: Headaches (GCA, SLE), neuropathies (vasculitis, SLE).
• Respiratory Symptoms: Pleurisy, interstitial lung disease (RA, SLE, scleroderma, myositis).
• Renal Involvement: Haematuria/proteinuria (SLE nephritis, ANCA-associated vasculitis).
• Gastrointestinal Symptoms: Oral ulcers (SLE), abdominal pain (vasculitis).

Diagnosis (Gold Standard)

Diagnosis in rheumatology is often a constellation of clinical, laboratory, and imaging findings, rather than a single 'gold standard' test. However, key investigations include:

• History & Clinical Examination: Paramount for identifying patterns (e.g., symmetrical polyarthritis, oligoarthritis, spondyloarthropathy features).
• Acute Phase Reactants: ESR and CRP (elevated in inflammatory conditions).
• Autoantibodies:
  • ANA (Antinuclear Antibody): Screening for SLE, Sjogren's, scleroderma, myositis. Specific extractable nuclear antigens (ENA) confirm diagnosis.
  • RF (Rheumatoid Factor) & Anti-CCP (Cyclic Citrullinated Peptide Antibody): Highly specific for Rheumatoid Arthritis (anti-CCP more specific and predictive of erosive disease).
  • ANCA (Anti-neutrophil Cytoplasmic Antibody): p-ANCA (MPO) and c-ANCA (PR3) for ANCA-associated vasculitides (e.g., Granulomatosis with Polyangiitis, Microscopic Polyangiitis).
  • Antiphospholipid Antibodies (Lupus anticoagulant, anti-cardiolipin, anti-beta2-glycoprotein I): For Antiphospholipid Syndrome (APS).
• Joint Fluid Aspiration: Differentiates inflammatory (high WBC, no organisms), septic (pus, organisms), and crystal-induced arthritis (urate crystals in gout, CPPD crystals in pseudogout).
• Imaging:
  • X-rays: Erosions (RA), sacroiliitis (AS), joint space narrowing, periosteal reaction.
  • Ultrasound: Detects synovitis, enthesitis, erosions, guides injections.
  • MRI: Early inflammatory changes (bone oedema, synovitis) in axial and peripheral joints.
• Biopsy:
  • Temporal Artery Biopsy: Gold standard for Giant Cell Arteritis (GCA).
  • Kidney Biopsy: For lupus nephritis, ANCA-associated glomerulonephritis.
  • Skin/Muscle Biopsy: For vasculitis, inflammatory myositis, scleroderma.

Management (First Line)

• Education & Lifestyle: Patient education, exercise, weight management, smoking cessation.
• Symptomatic Relief:
  • NSAIDs: For pain and stiffness in inflammatory conditions (monitor renal, GI, CV risk).
  • Paracetamol: For mild pain.
• Disease-Modifying Anti-Rheumatic Drugs (DMARDs):
  • Conventional Synthetic DMARDs (csDMARDs): Methotrexate (first-line for RA, PsA), Sulfasalazine, Hydroxychloroquine (mild SLE, RA), Leflunomide. Require regular monitoring for side effects (e.g., liver, bone marrow).
  • Biologic DMARDs (bDMARDs): TNF-alpha inhibitors (e.g., Adalimumab, Etanercept, Infliximab), IL-6 inhibitors (Tocilizumab), B-cell depletion (Rituximab), T-cell co-stimulation inhibitors (Abatacept). Used when csDMARDs fail.
  • Targeted Synthetic DMARDs (tsDMARDs): JAK inhibitors (e.g., Tofacitinib, Baricitinib). Oral alternatives to biologics.
• Corticosteroids: Bridging therapy for acute flares, GCA, PMR, severe SLE (often pulsed IV for acute nephritis/CNS involvement). Taper slowly to avoid adrenal insufficiency.
• Specific Treatments:
  • Gout: Acute: NSAIDs, colchicine, steroids. Prophylaxis: Allopurinol or Febuxostat (urate-lowering therapy).
  • Osteoporosis: Bisphosphonates, Calcium/Vitamin D.
  • Scleroderma: Symptom-directed (e.g., PPI for reflux, CCB for Raynaud's). Immunosuppression for organ involvement.