Clinical features, electroneurophysiology, neuroimaging and gene analysis of one juvenile dentatorubral-pallidoluysian atrophy pedigree

Abstract

Objective To explore the clinical features, electroneurophysiology, neuroimaging and gene characteristics of one juvenile dentatorubral-pallidoluysian atrophy (DRPLA) pedigree with an onset of epilepsy. Methods The clinical data of the elder sister and younger brother in a family with juvenile DRPLA were collected. Furthermore, their clinical manifestations, electroneurophysiology results, neuroimaging characteristics and atrophin-1 gene CAG repeat numbers were detected and analyzed in detail. Results There were four patients in this family in total. The probands were two siblings, and they both had the onset manifestation of epilepsy. The younger brother had frequently epileptic seizure, marked cerebellar ataxia, involuntary movement and mental retardation. Compared with her younger brother, the sister had light symptoms such as mild memory deterioration without ataxia and involuntary movement, and she could undertake some simple work. The spike wave and sharp wave complex can be detected in electroencephalogram (EEG) examination, the cortical center segment lesions pathological changes were revealed in somatosensory evoked potentials (EP), and the latency period of P300 was prolonged in the both siblings. Magnetic resonance imaging (MRI) showed that the younger brother had marked atrophies in the cerebral cortex, brainstem and cerebellum. Furthermore, MRI showed that the elder sister had only mild atrophies in the cerebral cortex, brainstem and cerebellum, and that on the contrary some abnormally high signals were observed in cerebral cortex but not white matter. DRPLA gene detection revealed that the numbers of CAG repeats were 15/68 (the younger brother) and 15/64 (the elder sister), respectively. Conclusions Epilepsy, especially the myoclonus, is a common clinical manifestation for juvenile DRPLA, and many other types of epileptic seizures may arise with the development of DRPLA. DRPLA has diverse clinical heterogeneity. EEG, EP and brain MRI examination are great for DRPLA diagnosis and differential diagnosis, and the specific gene detection can be helpful for a definitive diagnosis. Key words: Dentatorubral-pallidoluysian atrophy; Electrophysiology; Magnetic resonance imaging; Genetic testing