title: Etiology of pneumonitis in children with leukemia.
mesh_terms: D007945:Leukemia, Lymphoid / Q000150:complications* / Q000188:drug therapy; D008727:Methotrexate / Q000009:adverse effects / Q000627:therapeutic use; D011658:Pulmonary Fibrosis / Q000139:chemically induced / Q000209:etiology*
chemical_list: D008727:Methotrexate