Abstracts

Rett Syndrome (RS) is a neurodevelopmental disorder, preferentially found in females, that has a classical clinical presentation and typical EEG findings. The electroencephalogram (EEG) is invariably abnormal and shows characteristic, though not diagnostic, changes: loss of expected developmental features; the appearance of focal, multifocal, and generalized epileptiform abnormalities; and the occurrence of rhythmic slow (theta) activity primarily in the frontal-central regions. Epileptic seizures are reported to occur frequently in RS (70-80%). However, many events presumed to be seizures have no EEG correlate during video-EEG monitoring, suggesting the possibility of a nonepileptic mechanism. Status epilepticus (SE) in RS is not uncommon. However, SE may go unrecognized, particularly in cases of nonconvulsive SE.
To describe clinical and electrographic characteristics of four patients with RS who presented nonconvulsive SE. We studied four girls with confirmed RS who presented nonconvulsive status epilepticus. Clinical and EEG findings were tabulated with the Clinical Stage System of Hagberg and Witt-Engerström. Previous EEG findings were correlated. All patients were in transition of stage II to III and had antecedent of seizures. Clinical findings were suggestive of behavioral arrest, cyanosis and diminishment of movements, hand manipulations and episodes of hyperventilation. EEG was characterized by continuous partial activity in centroparietal or temporal area (2 patients), generalized ictal theta activity (1) and ictal generalized delta activity (1). Diagnosis of nonconvulsive SE in RS is sometimes difficult to be defined. Correlation with clinical and EEG findings is important in the treatment and follow up of these patients. (Supported by Instituto Israelita de Ensino e Pesquisa Albert Einstein.)