Impairment of cerebral biogenic amine synthesis in a patient receiving high-dose methotrexate

Abstract

A transient acute neurologic syndrome occurred in a 15-year-old boy receiving high-dose methotrexate (MTX) for acute lymphoblastic leukemia. Cerebrospinal fluid analysis revealed a decrease of homovanillic acid and 5-hydroxyindoleacetic acid concentrations with a rise of biopterin levels. These findings suggest that MTX can induce a transient alteration of the metabolism of tetrahydrobiopterin leading to the defect of biogenic amine neurotransmitter synthesis.