Polymyalgia Rheumatica

Snapshot

• A 50-year-old woman presents to her physician’s office for muscle pain and stiffness in the morning. She reports that this has been going on for a few months now and has been getting increasingly more painful. As a hair stylist, she reports that she now has to schedule her appointments in the afternoon, as her muscles are too stiff and sore to cut and style hair. She also reports that she occasionally gets low-grade fever with no other signs of infection. Physical exam reveals normal strength and slightly reduced range of movement. Laboratory exam reveals elevated erythrocyte sedimentation rate and C-reactive protein. Serum rheumatoid factor and antinuclear antibodies are normal. She is given systemic low-dose corticosteroids.

Introduction

• Clinical definition
  • chronic and inflammatory rheumatic disease characterized by muscle pain and stiffness
• Epidemiology
  • demographics
    • female > male
    • > 50 years of age
  • risk factors
    • winter months
    • viral infections
• Pathogenesis
  • pathogenesis is unclear but may be triggered by environmental factors such as winter or viral infections and inflammatory cytokines play a key role
• Associated conditions
  • giant cell arteritis (in ~20% of patients) 
• Prognosis
• ~50% of patients experience relapse

Presentation

• Symptoms
  • muscle pain and stiffness in the neck, shoulders, or pelvis for > 2 weeks
    • stiffness is more prominent in the morning
    • difficulty rising out of chair or lifting arms above head
  • constitutional symptoms
    • fatigue
    • low-grade fevers
    • weight loss
  • headache may indicate giant cell arteritis
• Physical exam
  • normal muscle strength
  • may have reduced active and passive range of movement
• joint swelling may be appreciated

Studies

• Labs
  • ↑ inflammatory markers
    • erythrocyte sedimentation rate
    • C-reactive protein
  • normal creatine kinase
  • autoantibodies typically absent
• Making the diagnosis
• based on clinical presentation and laboratory studies

Differential

• Rheumatoid arthritis 
• Spondyloarthropathy
• Adhesive capsulitis
• Fibromylagia

Treatment

• Management approach
  • if patients do not rapidly respond to low-dose corticosteroids, consider an alternative diagnosis
  • nonsteroidal anti-inflammatory drugs usually do not have any effect
• Medical
  • systemic low-dose corticosteroids
    • indications
      • initial therapy for patients with polymyalgia rheumatica
        • low-dose steroid response is usually rapid
        • consider supplementing with calcium and vitamin D for prevention of osteoporosis
  • methotrexate
    • indications
      • added to treatment regimen for patients on prolonged therapy, with inadequate response to steroids
• used in patients in whom steroids are contraindicated

Complications

• Blindness caused by giant cell arteritis