Clinical and electroencephalographic findings in juvenile type DRPLA

Periodic Epileptiform Discharges in Children With Advanced Stages of Progressive Myoclonic Epilepsy

Huntington's disease (HD) and dentatorubral-pallidoluysian atrophy (DRPLA) are monogenic forms of neurodegenerative disorders with autosomal dominant inheritance. Compared with adult-onset HD and DRPLA, children with these disorders are more severely affected and are known to manifest the devastating symptoms of progressive myoclonic epilepsy (PME) syndrome. In this report, we present a 6-year-old girl with HD from a family, and 2 siblings with DRPLA from another unrelated family. Serial neuroimaging and electroencephalography (EEG) studies showed that periodic epileptiform discharges and synchronized paroxysmal activity became prominent with their disease progression. Periodic complexes in EEG may emerge at advanced stages of childhood PME as a consequence of rapidly degenerating processes of their brain functions.

Juvenile dentatorubral-pallidoluysian atrophy: new clinical features

Dentatorubral-pallidoluysian atrophy is a rare autosomal-dominant neurodegenerative disorder caused by an expansion of a CAG repeat in the atrophin-1 gene on chromosome 12. Dentatorubral-pallidoluysian atrophy is characterized clinically by prominent anticipation and a wide variety of symptoms that depend on age of onset and number of trinucleotide repeats. The juvenile type of dentatorubral-pallidoluysian atrophy, like Huntington's disease, is most commonly inherited via paternal transmission of the gene and most frequently presents with early-onset progressive myoclonus epilepsy with mental retardation and ataxia. We present six affected individuals with dentatorubral-pallidoluysian atrophy from a black family living in North America. This pedigree includes two severe juvenile-onset cases, one of maternal transmission and the other of paternal transmission. Both cases of juvenile-onset disease presented with autistic features and seizures. Interestingly, cranial magnetic resonance imaging performed on the more affected child revealed only mild cerebellar atrophy. The present family expands the clinical description of juvenile-onset dentatorubral-pallidoluysian atrophy and emphasizes the importance of considering dentatorubral-pallidoluysian atrophy in children with progressive myoclonus epilepsy.

Chorea and its disorders

Chorea (Greek for "dance") refers to irregular, rapid, flowing, non-stereotyped and random involuntary movements that often possess a writhing quality, referred to as choreoathetosis. When mild, it may be difficult to differentiate from restlessness. The movements can be strikingly asymmetric, as in hemichorea, or generalized. When chorea is proximal and of large amplitude, it is called ballism. Chorea is worsened by stress and anxiety and subsides during sleep. Movements can interfere with the completion of many daily activities, making fastening a button a substantial effort. Chorea often is incorporated into a purposeful activity in an attempt to disguise it. Motor impersistence is a common associated feature, demonstrated by varying intensity of grip strength (milkmaid's grasp) or by an inability to sustain eye closure or tongue protrusion.