[Myoclonus epilepsy in children and adolescents].

Twelve cases of myoclonus epilepsy initiating in childhood and adolescence were studied clinically, electrophysiologically and biochemically. Myoclonic and epileptic syndromes being most pronounced, the clinical pattern presented certain polymorphism: asymmetry, hyperkinesis, myodystonia, epileptic episodes, mental disorders. The electroencephalographic picture of the disease was variable. Hyperexcretion of glycosaminoglycans and changes in their fraction composition with predominant release of heparan sulphate evidenced for deranged metabolism of mucopolysaccharides.