関節リウマチに対するメトトレキセート治療中に高度の汎血球減少を来し死亡した5例の検討

Background : Methotrexate （MTX） is placed as an anchor drug of treatment for rheumatoid arthritis （RA）. However, many cases suffered from side effects of MTX such as interstitial pneumonia and hematological toxicity. We investigated ５ cases that died of severe pancytopenia under treatment with low-dose MTX for RA.
Methods : We reviewed the clinical features of ５ cases that developed severe pancytopenia and were transferred to Tokushima Prefectural Central Hospital under treatment with low-dose MTX for RA from ２０１１-２０１５.
Results : All the cases were women, and were under treatment with low-dose MTX. The periods of medication of MTX were not clear. All the cases had renal insufficiency, and had a severe infection induced by pancytopenia and some cases developed disseminated intravascular coagulation （DIC）. At once we started intensive care, but all patients died in a short term.
Conclusions : Women, the elderly, and renal insufficiency can be risk factors of severe pancytopenia induced by MTX even if low dosage. We should carefully treat these patients with MTX.