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Leflunomide-induced polymyositis in a patient with rheumatoid arthritis

Sae Ochi1, Ken Taniguchi, Masakazu Nagashima

  • 1Department of Rheumatology, Tokyo Metropolitan Bokutoh Hospital, 4-23-15 Kohtohbashi, Sumida-ku, Tokyo 130-8575, Japan. ochisae@bokutoh-hp.metro.tokyo.jp

Modern Rheumatology
|June 16, 2009
PubMed

Insights

A rare case of polymyositis (PM), an autoimmune muscle inflammation, developed after rheumatoid arthritis (RA) treatment with leflunomide. Clinicians should consider this rare adverse event, especially with elevated transaminases.

Area of Science:

  • Rheumatology
  • Autoimmune Diseases
  • Pharmacovigilance

Background:

  • Rheumatoid arthritis (RA) and polymyositis (PM) are significant autoimmune conditions.
  • The co-occurrence of RA and PM is infrequently observed in clinical practice.

Observation:

  • A patient with RA treated with leflunomide developed polymyositis (PM).
  • The patient's PM responded to prednisolone (PSL) and methotrexate (MTX), but RA symptoms recurred during treatment.

Findings:

  • The clinical progression suggests leflunomide-induced PM in this RA patient.
  • This case highlights a rare but potential adverse effect of leflunomide therapy.

Implications:

  • Clinicians should be vigilant for PM development in RA patients treated with leflunomide.
  • Consider leflunomide-induced myositis in patients presenting with unexplained transaminase elevation.
  • This finding contributes to understanding rare drug-induced autoimmune conditions.

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