CSF2 and Decreased total neutrophil count: Similarly, pancytopenia was shown in 82.1 % of patients in a study by Kivity et al., with almost one-third of the patients developing severe neutropenia (neutrophil count less than 500). While the administration of leucovorin and GM-CSF are both important in the treatment of methotrexate toxicity, it is important to note that the outcomes can be unfavorable.