JUVENILE MYOCLONIC EPILEPSY (JANZ-SYNDROM E) - A WELL-KNOWN EPILEPSY SYNDROME

Juvenile myoclonic epilepsy (JME) was described electroclinically by J anz and Christian in 1957 and consists of myoclonic jerks in varying c ombination with the absence of seizures and generalized tonic-clonic s eizures, a typical circadian distribution on awakening, sleep deprivat ion,alcohol consumption and flickering stimuli as characteristic preci pitating factors, typical EEG abnormalities with generalized epileptif orm discharges, normal physical and neuroradiological findings, and of ten a family history of epilepsy. although the misdiagnosis of this we ll-classified and easily treatable syndrome is supposed to occur rarel y in Germany, we retrospectively investigated how often the wrong init ial classification had been made among patients who were finally treat ed in our outpatient epilepsy unit. Between 1993 and 1995, 30 patients with a typical JME-like symptom constellation were identified who had been misdiagnosed initially. In all patients, localization-related ep ilepsy had been classified, although regional EEG abnormalities were r are (n=5). All patients reported the typical circadian distribution, a bnormal neuroradiological findings were absent, and typical EEG abnorm alities were present in all cases. Under treatment with appropiate ant iepileptic drugs 97% of the patients became almost completely seizure- free. Even 40 years after the first description of the syndrome,JME is an underdiagnosed illness. The generally positive course underlines t he importance of its correct identification.