Benign myoclonic epilepsy of infancy evolving to Jeavons syndrome.

Benign myoclonic epilepsy of infancy is a rare idiopathic generalized epileptic syndrome occurring below the age of 3 years. Although benign outcome is presumed, some recent studies suggest less favorable outcome. A 14-year-old boy had a history of repeated episodes of myoclonic jerks of the shoulders and upper limbs in infancy (age 5 months). An ictal electroencephalogram indicated generalized spike-wave discharges associated with the myoclonic seizures, and the diagnosis of benign myoclonic epilepsy of infancy was made. Valproate treatment resulted in control of the myoclonic seizures, and the drug was withdrawn when the patient was 5 years of age. At the age of 10, he presented with episodes of eyelid jerks associated with brief lapses in concentration triggered by sunlight. Electroencephalography revealed photosensitivity and a pattern of eye-closure sensitivity. These features were compatible with the diagnosis of eyelid myoclonia with absences, or Jeavons syndrome. Lamotrigine eliminated the seizures. The evolution of benign myoclonic epilepsy of infancy to eyelid myoclonia with absences has been reported in one other case. A possible continuum of myoclonic epileptic syndromes, mediated by a common genetic abnormality, suggests the need for longer monitoring of patients with benign myoclonic epilepsy of infancy.