[Pancytopenia induced by two low-dose injections of methotrexate in a patient treated for ulcerative colitis].

A 72 year-old man with steroid-dependent ulcerative colitis was treated with methotrexate at 25 mg subcutaneous weekly. Three days after the second injection of methotrexate a pancytopenia occurred associated with a Klebsiella pneumoniae septicemia which evolution was favourable under treatment. Pancytopenia is a rare but severe adverse effect of low-dose methotrexate therapy. In our patient the risk factors were age upper than 65 years, renal insufficiency and hypoalbuminemia. This report emphasizes the need for a close monitoring of hematologic tests after onset of methotrexate particularly if some risk factors are present.