Hypersensitivity Pneumonitis Associated with Leflunomide Therapy

NEIL MARTIN, J. ALASTAIR INNES, C. MICHAEL LAMBERT, COLIN M. TURNBULL, and WILLIAM A.H. WALLACE

ABSTRACT.

Disease progression in rheumatoid arthritis is controlled with disease modifying drugs, many of which have toxic side effects. Pulmonary side effects are common and this has resulted in the development of newer medications with less pulmonary toxicity. We observed that even these newer drugs can be associated with potentially very serious pulmonary toxicity, with hypersensitivity pneumonitis developing after the initiation of leflunomide therapy. We urge caution in the use of leflunomide in patients with pulmonary side effects from other drugs or who have underlying pulmonary disease. (First Release July 1 2007; J Rheumatol 2007;34:1934-7)

Key Indexing Terms:

HYPERSENSITIVITY PNEUMONITIS
LEFLUNOMIDE
RHEUMATOID ARTHRITIS

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From Western General Hospital and Edinburgh Royal Infirmary, Edinburgh, United Kingdom.

N. Martin, BSc, MRCP(UK), MFSEM, SpR Respiratory and General (Internal) Medicine; J.A. Innes, BSc, PhD, FRCPE, Consultant Chest Physician; C.M. Lambert, MD, FRCP, Consultant Rheumatologist; C.M. Turnbull, BSc, FRCPE, FRCR, Consultant Radiologist, Western General Hospital; W.A.H. Wallace, PhD, FRCPE, FRCPath, Consultant Pathologist, Edinburgh Royal Infirmary.

Address reprint requests to Dr. N. Martin, SpR Respiratory Medicine, Respiratory Medicine Unit, Western General Hospital, Crewe Road South, Edinburgh, EH4 2XU, UK. E-mail: nmartin@doctors.org.uk

Accepted for publication May 3, 2007.

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