Seizures following intrathecal cytosine arabinoside in young children with acute lymphoblastic leukemia.

Two young children (3 1/2 years and 19 months) developed seizures within 24 hours of receiving intrathecal cytosine arabinoside. Both had previously received intrathecal cytosine and methotrexate as well as cranial irradiation without untoward effect. Possible mechanisms of causation are discussed and caution is stressed for use of intrathecal cytosine arabinoside in young children.