Nonconvulsive status epilepticus in adults and children.

Nonconvulsive status epilepticus (SE) accounts for approximately one-quarter of all cases of SE. The actual proportion may be higher because patients with nonconvulsive SE may go unidentified. This disorder may be divided into generalized (absence) or partial (complex partial) forms. Nonconvulsive SE may occur de novo or in patients with epilepsy. Absence SE is considered more frequent and is characterized by a continuous neurocognitive alteration. Complex partial SE may be associated with recurrent seizure activity and a cycling of the clinical states. Treatment includes antiepileptic drug(s) (AEDs) and avoidance of seizure precipitants. Electrophysiological studies are necessary to confirm the diagnosis of nonconvulsive SE and to monitor the response to AED therapy. Prompt recognition and treatment may be necessary to avoid neurological morbidity in select patients. Epilepsy with continuous spikes and waves during slow sleep (ESES) and the Landau-Kleffner syndrome are two rare childhood disorders that are difficult to classify but may be appropriate to include in a discussion of nonconvulsive SE.