Methotrexate for corticosteroid-resistant polymyalgia rheumatica and giant cell arteritis

Area of Science:

• Rheumatology
• Immunology
• Pharmacology

Background:

• Giant cell arteritis (GCA) and polymyalgia rheumatica (PMR) are common systemic vasculitides in the elderly.
• Corticosteroids, primarily prednisone, are the mainstay of treatment for GCA and PMR.
• Long-term corticosteroid use is associated with significant adverse effects.

Observation:

• Three patients diagnosed with GCA (two biopsy-proven) and PMR (one) were treated with prednisone (40-60 mg daily).
• Initial prednisone treatment yielded a good response in all patients.
• Symptom exacerbation and elevated Westergren sedimentation rates (WSR) occurred upon prednisone dose reduction.

Findings:

• The addition of methotrexate (7.5-12.5 mg/wk) to prednisone therapy led to symptom improvement.
• Methotrexate treatment resulted in a decrease in WSR, indicating reduced inflammation.
• Methotrexate demonstrated a steroid-sparing effect, allowing for lower prednisone dosages.

Implications:

• Methotrexate may be an effective steroid-sparing agent in managing GCA and PMR.
• Combining methotrexate with prednisone could mitigate long-term corticosteroid toxicity.
• Further research is warranted to confirm the efficacy and safety of methotrexate in larger cohorts.