dextromethorphan and Precursor-Cell-Lymphoblastic-Leukemia-Lymphoma

Acute lymphoblastic leukemia is the most common malignancy in children. Long-term survival exceeds 90%; however, therapy-induced toxicity remains a concern. Methotrexate neurotoxicity (MTX-NT) is common, often necessitating alterations in chemotherapy regimens. Dextromethorphan has been used as an abortive and prophylactic treatment for MTX-NT. The authors report a case series of 7 pediatric patients with acute lymphoblastic leukemia with prior episodes of MTX-NT given a single dose of dextromethorphan (1 to 2 mg/kg) on the day of MTX administration and 7 days later. No subsequent episodes of MTX-NT occurred after 40 intravenous and 81 intrathecal administrations. This specific regimen of secondary prophylaxis may prevent MTX-NT.

Topics: Adolescent; Adult; Antimetabolites, Antineoplastic; Child; Child, Preschool; Dextromethorphan; Excitatory Amino Acid Antagonists; Female; Follow-Up Studies; Humans; Injections, Intravenous; Injections, Spinal; Male; Methotrexate; Neurotoxicity Syndromes; Precursor Cell Lymphoblastic Leukemia-Lymphoma; Prognosis; Retrospective Studies; Secondary Prevention; Young Adult

Acute lymphoblastic leukemia (ALL) is the most common form of childhood leukemia. The treatment of ALL involves multimodality therapy, and methotrexate (MTX) remains a mainstay of treatment. A complication of MTX therapy includes acute, subacute, and chronic neurotoxocity. Signs and symptoms may range from headaches, dizziness, and mood disorders to seizures and stroke-like symptoms.. An 18-year-old woman with a history of ALL presented to the emergency department with acute onset of right-sided facial paralysis, right upper extremity flaccid paralysis, and right lower extremity weakness after receiving MTX therapy 3 days earlier. Diagnostic studies were unremarkable and the patient was treated with oral dextromethorphan for presumed MTX-induced neurotoxicity. The patient's symptoms began to improve within hours and she was discharged home within 48 hours with no neurologic deficits. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Emergency physicians should be aware of this complication of MTX therapy given the sensitivity in regards to time with respect to cerebral vascular accidents. An awareness of this complication in the setting of the appropriate history and physical examination can lead to an accurate diagnosis and intervention and the avoidance of administering thrombolytics.

Topics: Adolescent; Antimetabolites, Antineoplastic; Combined Modality Therapy; Dextromethorphan; Emergency Service, Hospital; Excitatory Amino Acid Antagonists; Facial Paralysis; Female; Humans; Lower Extremity; Methotrexate; Muscle Hypotonia; Muscle Weakness; Neurotoxicity Syndromes; Precursor Cell Lymphoblastic Leukemia-Lymphoma; Stroke; Upper Extremity