Prevention of neurotoxicity by high-dose folinic acid rescue after high-dose methotrexate and intrathecal methotrexate without compromising cure inspite of previous transient leukoencephalopathy after intrathecal methotrexate.

Dear Editor, Methotrexate (MTX) is a frequently used chemotherapeutic agent in the treatment of childhood acute lymphoblastic leukaemia (ALL) and lymphoma. Besides oral and intravenous MTX, intrathecal MTX is an essential component of chemotherapy for ALL and is effective in preventing recurrences of central nervous system (CNS) leukaemia. Acute, subacute and chronic neurotoxicity have been observed after the administration of high-dose intravenous and/or intrathecal MTX.1 The incidence varies with the route of administration, with less than 10% of those treated intravenously developing some neurotoxicity compared with up to 40% of patients treated intrathecally in combination with intravenous therapy.2