Is it juvenile myoclonic epilepsy?

A 21-year old man with marked developmental delay was referred for the diag nosis of myoclonic jerks (MI), which were sometimes responsible for sudden falls without loss of consciousness, that had begun 2 years before, and for a recent generalized tonic-clonic seizure preceded by a cluster of MJ. Phy sical examination revealed a small stature, bilateral pyramidal signs, seve re mental retardation, and retinis pigmentosa. Etiological factors for this encephalopathy were not found (muscle and skin biopsies, karyotype and ext ensive blood chemistry). Waking interictal EEC showed a normal background a ctivity and generalized poly-spike-and wave (PSW) discharges. Photic stimul ation disclosed a marked photoparoxysmal response, sometimes associated wit h myoclonic jerks. Three spontaneous jerks accompanied by a burst of genera lized PSW were recorded on awakening from a nap. The MRI disclosed wide ven tricles, a thin corpus callosum, brainstem atrophy and a so-called "redunda nt gyration"; these changes were evocative of acquired perinatal damage. Ju venile myoclonic epilepsy (JME) was diagnosed and valproate was started res ulting in complete control of seizures. During a 5-year follow-up, the pati ent has remained seizure-free and the EEG consistently normal. In our opini on, JME can be diagnosed in very uncommon settings, including patients with significant brain damage, as long as all the other criteria for the diagno sis are present.