Clinical characteristics of patients with rheumatoid arthritis and methotrexate induced pneumonitis

J Rheumatol. 1997 Dec;24(12):2299-303.

Abstract

Objective: To determine the clinical features of methotrexate (MTX) pneumonitis in patients treated for rheumatoid arthritis (RA).

Methods: The medical records of 284 patients with RA who had been treated with oral MTX (mean followup 33.2 mo) were reviewed retrospectively.

Results: MTX induced interstitial pneumonitis developed in 6 patients (2.1%). The affected patients were significantly older than those without MTX pneumonitis (67.3 +/- 9.8 vs 52.4 +/- 12.6 yrs, respectively; p < 0.005). The cumulative MTX dose ranged from 65 to 580 mg at the time pneumonitis developed. Five of the patients (83%) had preexisting interstitial abnormalities, while only 29 of the 278 patients without MTX pneumonitis (10%) had such abnormalities (p < 0.001). The frequency of adverse effects due to previous treatment with disease modifying antirheumatic drugs (DMARD) was 66.7% in MTX pneumonitis patients and 14.3% in the other 278 patients (p < 0.01).

Conclusion: Advanced age, preexisting interstitial abnormalities, and previous adverse reactions to DMARD may be associated with MTX pneumonitis. Patients with these characteristics require careful monitoring during MTX therapy.

MeSH terms

  • Adult
  • Aged
  • Antirheumatic Agents / adverse effects*
  • Arthritis, Rheumatoid / drug therapy*
  • Creatinine / blood
  • Cytomegalovirus Infections / diagnosis
  • Diagnosis, Differential
  • Female
  • Humans
  • Male
  • Methotrexate / adverse effects*
  • Middle Aged
  • Pneumonia / chemically induced*
  • Pneumonia / diagnosis
  • Pneumonia / epidemiology
  • Pneumonia, Pneumocystis / diagnosis
  • Retrospective Studies
  • Risk Factors

Substances

  • Antirheumatic Agents
  • Creatinine
  • Methotrexate