Nonconvulsive status epilepticus due to ifosfamide

To report 2 cases of nonconvulsive status epilepticus (NCSE) following infusion of ifosfamide.

Two patients who received ifosfamide-containing chemotherapy developed NCSE. One woman received ifosfamide 1000 mg/m2 (1 h infusion on days 1-5); confusion, lethargy, and speech deterioration developed on day 3. The second patient developed similar symptoms on day 3 of treatment with 2500 mg/m2. Both patients responded to intravenous administration of diazepam 10 mg and were given levetiracetam as maintenance therapy.

The severity and presentation of central nervous system toxicity due to ifosfamide varies greatly and involves a spectrum ranging from subclinical electroencephalogram changes to coma. NCSE, an epileptic disorder in which typical convulsive activity is absent, has previously been reported in only 4 patients receiving ifosfamide. Levetiracetam may be used for maintenance antiepileptic therapy after diazepam administration.

Among the many presentations of ifosfamide neurotoxicity, clinicians should consider NCSE as a possible explanation for changes in consciousness in a patient receiving this agent. An objective causality assessment by use of the Naranjo probability scale revealed that NCSE due to ifosfamide was probable.