Concurrent acute megaloblastic anaemia and pneumonitis: a severe side-effect of low-dose methotrexate therapy during rheumatoid arthritis.

In a patient suffering from rheumatoid arthritis, we report the first simultaneous occurrence of two side effects of low-dose methotrexate: an acute megaloblastic anaemia and a pneumonitis. A combination of methotrexate suspension, folinic acid and corticosteroids led to recovery. The correlation between the haematologic and pneumologic toxicity is discussed.