[A 5-year-old boy with nonconvulsive status epilepticus induced by theophylline treatment]

A normally developed 5-year-old boy with no history of convulsive disorder presented with a generalized tonic-clonic convulsion on the second day of oral theophylline therapy. Although the convulsive seizure was abolished by an intravenous bolus of diazepam, he did not regain consciousness. Emergency electroencephalography disclosed continuous irregular seizure activity, occurring predominantly over the right hemisphere, indicating a diagnosis of nonconvulsive status epilepticus (NCSE). The serum theophylline concentration was 19.7 microg/mL. Treatment with an initial intravenous bolus of midazolam (0.26 mg/kg) largely restricted seizure activity to the right hemisphere, with activity then diminishing to continuous right occipital spikes. An additional 0.24 mg/kg bolus followed by continuous infusion at a rate of 0.20 mg/kg/hr completely abolished electrical status. Our case suggests that theophylline treatment can provoke NCSE even after successful control of a brief convulsion by initial antiseizure treatment in some patients predisposed toward localization-related epilepsy. This possibility should be kept in mind in any child receiving theophylline who presents with sustained unconsciousness.