Epilepsia mioclónica progresiva secundaria a enfermedad por cuerpos de Lafora / Progressive myoclonic epilepsy secondary to Lafora's body disease

La enfermedad de Lafora es infrecuente; sin embargo, es una de las causas más comunes de epilepsia mioclónica progresiva. Presentamos el caso de una mujer de 19 años sin comorbilidades y pautas madurativas normales, que inició a los 8 años con convulsiones y que a partir de los 15 años agregó deterioro cognitivo progresivo. Fue internada en nuestra institución con diagnóstico de estatus epiléptico super refractario. Se diagnosticó enfermedad de Lafora, confirmada por la anatomía patológica, y posteriormente se realizó un test genético que informó una variante patogénica del gen EPM2A, que confirmó el diagnóstico. Presentamos una causa de epilepsia mioclónica progresiva, con un pronóstico ominoso y un tratamiento orientado a medidas paliativas, por lo que es importante analizar los diagnósticos diferenciales con otras entidades, a fin de establecer un pronóstico, ofrecer mejor calidad de vida, asistencia médica adecuada y brindar asesoría genética a los familiares.

Lafora's disease is infrequent. However, it is one of the most common causes of progressive myoclonus epilepsy. We present the case of a 19-year-old woman, without comorbidities and normal development that started at 8 years with seizures and that from 15 years, had progressive cognitive deterioration. She was admitted to our institution with a diagnosis of super refractory status epilepticus. The diagnosis of Lafora's disease was made through pathological anatomy, later a genetic test was performed that reported a pathogenic variant of the EPM2A gene, confirming the diagnosis. We present a cause of progressive myoclonic epilepsy, with an ominous prognosis and a treatment oriented to palliative measures, so it is important to analyze the differential diagnoses with other entities, in order to establish a prognosis, offer better quality of life, adequate medical care and provide genetic counseling to family members.

CLN6 Mutation in a Patient with Progressive Myoclonus Epilepsy / 대한소아신경학회지

Neuronal ceroid lipofuscinoses (NCLs) are inherited neurodegenerative disorders, which are caused by the accumulation of lipopigment in lysosomes. Variant forms of late infantile NCLs (vLINCLs) characterized by a later onset of seizures and visual impairment (3–8 years) than in the classic form (2–4 years) are caused by mutations of the gene encoding ceroid lipofuscinosis neuronal protein 6 (CLN6). In a girl with progressive myoclonus epilepsy, we found heterozygous variants of CLN6 (NM_017882.2; NP_060352.1): c.296A>G (p.Lys99Arg) and c.307C>T (p.Arg103Trp). They were identified with whole-exome sequencing and verified with Sanger sequencing. At 7 years and 9 months, our patient had developed multiple types of seizures, prominent myoclonus with photosensitivity, regression in motor and language skills, pyramidal and extrapyramidal signs, and brain atrophy in brain images, all of which were progressive and were compatible with vLINCLs. However, this first Korean report shows no visual impairment, which resembles the previously reported Japanese case.

First Molecular Diagnosis of a Patient with Unverricht-Lundborg Disease in Korea

Unverricht-Lundborg disease (ULD) is a form of progressive myoclonus epilepsy characterized by stimulation-induced myoclonus and seizures. This disease is an autosomal recessive disorder, and the gene CSTB, which encodes cystatin B, a cysteine protease inhibitor, is the only gene known to be associated with ULD. Although the prevalence of ULD is higher in the Baltic region of Europe and the Mediterranean, sporadic cases have occasionally been diagnosed worldwide. The patient described in the current report showed only abnormally enlarged restriction fragments of 62 dodecamer repeats, confirming ULD, that were transmitted from both her father and mother who carried the abnormally enlarged restriction fragment as heterozygotes with normal-sized fragments. We report the first case of a genetically confirmed patient with ULD in Korea.

Successful Treatment with Olanzapine of Psychosis in Dentatorubral-pallidoluysian Atrophy: A Case Report

Patients with dentatorubral-pallidoluysian atrophy occasionally elicit psychosis. So far, one study reported first generation antipsychotics drugs may provide an effective treatment; however, there is no literature on the benefits of second generation antipsychotics. We report on a 44-year-old man with dentatorubral-pallidoluysian atrophy whose psychotic symptoms were effectively treated with olanzapine. Our observation suggests some second generation antipsychotics provide a therapeutic option for ameliorating psychosis in dentatorubral-pallidoluysian atrophy.

Advances in research of SCARB2 functions and related disorders / 中华医学遗传学杂志

SCARB2 (scavenger receptor class B, member 2) is a lysosomal membrane glucoprotein, which is encoded by SCARB2 gene. It takes vital parts in the physiological and pathological processes including the transportation of beta-glucocerebrosidase to the lysosome, infection of EV71 and load-induced cardiac myocyte hypertrophy. This article has reviewed the molecular structure and functions of SCARB2 gene and its protein, as well as their relationship with diseases.

Genetics and clinical study of Chinese kindreds with dentatorubral pallidoluysian atrophy / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To investigate genetics and clinical characteristics of dentatorubral-pallidoluysian atrophy (DRPLA) in Chinese kindreds.</p><p><b>METHODS</b>Fragment analysis with laser-induced fluorescence in capillary electrophoresis was performed for the cytosine-adenine-guanine (CAG) repeats of DRPLA gene in 708 probands of autosomal dominant ataxia pedigrees and 119 sporadic ataxia cases.</p><p><b>RESULTS</b>Expanded CAG repeats of DRPLA gene were detected in probands of three ataxia pedigrees, with the numbers of repeats being 16/58, 16/58 and 14/54, respectively. In addition to ataxia, patients with adult-onset disease also exhibited spasm and neck torsion.</p><p><b>CONCLUSION</b>Only three cases of DRPLA have been identified among 827 cases, which suggested that DRPLA is a relatively rare subtype of SCA in Chinese population. Clinical variation among the patients suggested DRPLA has a wide spectrum of phenotype.</p>

Clinical and genetic analysis of 29 Brazilian patients with Huntington's disease-like phenotype / Análise clínica e genética em 29 pacientes Brasileiros com fenótipo doença de Huntington-símile

Huntington's disease (HD) is a neurodegenerative disorder characterized by chorea, behavioral disturbances and dementia, caused by a pathological expansion of the CAG trinucleotide in the HTT gene. Several patients have been recognized with the typical HD phenotype without the expected mutation. The objective of this study was to assess the occurrence of diseases such as Huntington's disease-like 2 (HDL2), spinocerebellar ataxia (SCA) 1, SCA2, SCA3, SCA7, dentatorubral-pallidoluysian atrophy (DRPLA) and chorea-acanthocytosis (ChAc) among 29 Brazilian patients with a HD-like phenotype. In the group analyzed, we found 3 patients with HDL2 and 2 patients with ChAc. The diagnosis was not reached in 79.3 percent of the patients. HDL2 was the main cause of the HD-like phenotype in the group analyzed, and is attributable to the African ancestry of this population. However, the etiology of the disease remains undetermined in the majority of the HD negative patients with HD-like phenotype.

A doença de Huntington (DH) é uma doença neurodegenerativa caracterizada por coréia, alterações comportamentais e demência, causada por uma expansão patológica do trinucleotídeo CAG no gene HTT. Vários pacientes têm sido descritos com o fenótipo típico para a DH porém sem a mutação esperada. O objetivo deste estudo foi avaliar a ocorrência de doenças como doença de Huntington-símile 2 (DHS-2), ataxias espinocerebelares tipo 1, 2, 3 e 17, atrofia dentatorubral-palidoluisiana e coreo-acantocitose (CAc) entre 29 pacientes brasileiros com fenótipo doença de Huntington-símile. No grupo analisado, encontramos 3 pacientes com DHS-2 e 2 pacientes com CAc. O diagnóstico permaneceu obscuro em 79,3 por cento dos pacientes. DHS-2 foi a principal causa do fenótipo DH-símile no grupo analisado, provavelmente devido a ancestralidade africana na população brasileira. Entretanto, a etiologia permaneceu indeterminada na maioria dos pacientes avaliados.

Polynucleotide repeat expansion of nine spinocerebellar ataxia subtypes and dentatorubral-pallidoluysian atrophy in healthy Chinese Han population / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To assist the establishment of platform and provide the reference standard for mutation detection in spinocerebellar ataxia (SCA) subtypes 1, 2, 3, 6, 7, 8, 10, 12, 17 and dentatorubral-pallidoluysian atrophy (DRPLA) in Chinese Han population.</p><p><b>METHODS</b>The nucleotide repeat numbers of the 9 SCA subtypes and DRPLA were detected using fluorescence-PCR and capillary gel electrophoresis technique in 300 healthy Chinese Han individuals.</p><p><b>RESULTS</b>Among the 300 healthy controls, the range of the CAG trinucleotide repeat number was 17 to 35 in SCA1, 14-28 in SCA2, 13-41 in SCA3/MJD, 4-16 in SCA6, 5-17 in SCA7, 5-21 in SCA12, 23-41 in SCA17, and 12-33 in DRPLA; and the range of CTA/CTG trinucleotide repeat number on SCA8 locus was 12-43 and the range of ATTCT pentanucleotide repeat number on SCA10 locus was 9-32. Of which, the 12 CTA/CTG repeats of SCA8, 9 ATTCT repeats of SCA10, 23 CAG repeats of SCA17 were the shortest normal repeat number, while the 41 CAG repeats of SCA3/MJD, 32 CAG repeats of SCA10 were the largest normal number that have not been reported.</p><p><b>CONCLUSION</b>The normal ranges of polynucleotide repeats of different subtypes of SCA vary with geographical areas and ethnicities. It might be associated with the genetic and ethnic backgrounds. This is the first normal reference standard of polynucleotide repeat number of these ten SCA subtypes in Chinese Han.</p>

Progressive Myoclonus Epilepsy Associated with Macular Cherry-Red Spots

Myoclonus, generalized epilepsy, and progressive neurological decline characterize progressive myoclonus epilepsy. A 25-year-old woman was admitted for the evaluation of seizure, progressive myoclonus and ataxic gait. Her symptoms had developed since she was 13 years old. She did not have facial dysmorphism, hepatosplenomegaly, or dementia. Fundoscopic evaluation revealed cherry-red spots in both macular regions. Biochemical assays of hexosaminidase A, beta-galactosidase, and neuraminidase in leukocytes and urine mucopolysaccharides were free of any abnormality. The patient might have an unknown type of lysosomal storage disease.

A Case of Dentatorubropallidoluysian Atrophy with Progressive Myoclonus Epilepsy

The dentatorubropallidoluysian atrophy (DRPLA) is a neurodegenerative disorder with expansion of an unstable CAG trinucleotide repeat in a gene on chromosome 12 and a rare cause of progressive myoclonus epilepsy (PME). A 34-year-old female showed progressive myoclonus, choreoathetosis, generalized tonicclonic seizure, dementia and ataxia. Her uncle died during convulsion at the age of 19. Brain MRI revealed cerebral, cerebellar and brainstem atrophy accompanied by dilatation of the fourth ventricle. The demonstration of expanded CAG repeat (67/11) in the gene for DRPLA was used to confirm the diagnosis. (J Korean Neurol Assoc 19(2):173~175, 2001)

A Case of Dentatorubropallidoluysian Atrophy with Progressive Myoclonus Epilepsy

The dentatorubropallidoluysian atrophy (DRPLA) is a neurodegenerative disorder with expansion of an unstable CAG trinucleotide repeat in a gene on chromosome 12 and a rare cause of progressive myoclonus epilepsy (PME). A 34-year-old female showed progressive myoclonus, choreoathetosis, generalized tonicclonic seizure, dementia and ataxia. Her uncle died during convulsion at the age of 19. Brain MRI revealed cerebral, cerebellar and brainstem atrophy accompanied by dilatation of the fourth ventricle. The demonstration of expanded CAG repeat (67/11) in the gene for DRPLA was used to confirm the diagnosis. (J Korean Neurol Assoc 19(2):173~175, 2001)

Two Cases of Progressive Myoclonus Epilepsy due to Gaucher's Disease, Type 3

Gaucher's disease is an autosomal recessive disorder caused by a deficiency of beta-glucosidase (glucocerebrosidase) which results in an accumulation of glucocerebroside in various organs and tissues. Type 3 (juvenile or subacute neuro-pathic) Gaucher's disease, presented here as progressive myoclonus epilepsy, occurs more rarely than type 1 (adult or nonneuropathic) or type 2 (infantile or neuropathic) Gaucher's disease. Two patients (brother and sister) with type 3 Gaucher's disease had or was expected to develop typical features of progressive myoclonus epilepsy: myoclonus, seizures, dementia, and cerebellar dysfunction. One of them showed Gaucher cells in a liver biopsy specimen and decreased beta-glucosidase activity (14% of normal) in the cultured skin fibroblasts, which confirmed the clinical diagno-sis of type 3 Gaucher's disease.

Myoclonus and epilepsies.

The possible associations of myoclonic phenomenae, progressive or non-progressive encephalopathies and epileptic features are reviewed, with special emphasis on pediatric age. This leads to recognize the following five groups of conditions: (1) Myoclonus without encephalopathy and without epilepsy; (2) Encephalopathies with non-epileptic myoclonus; (3) Progressive encephalopathies presenting myoclonus seizures of epileptic syndromes (Progressive myoclonus epilepsies); (4) Epileptic encephalopathies with myoclonic seizures; (5) Myoclonic epilepsies. Within the first group, which also includes physiologic myoclonus, a more thorough description of "Benign sleep myoclonus of newborn" and "Benign myoclonus of early infancy" is given. Characteristics of group 2 are "Kinsbourne Syndrome" and certain types of "Hyperekplexia" which pose interesting differential diagnosis with stimulus-sensitive epilepsies. In group 3, the concept of progressive encephalopathies is stressed. The fourth group refers to severe epilepsies, mainly on infancy and childhood, which lead to mental retardation irrespective of their aetiology. Group 5 comprises the true myoclonic epilepsies, differentiating syndromes recognized as idiopathic--such as "Benign myoclonic epilepsy of infancy" and "Juvenile myoclonic epilepsy"--from those which are cryptogenic and carry a more cautious prognosis--as "Cryptogenic myoclonic and myoclonoastatic epilepsies" and "Severe myoclonic epilepsy of infancy". Other epileptic syndromes not usually considered as myoclonic epilepsies, but presenting sometimes as myoclonic seizures, are finally referred.

A Case of Myoclonus Epilepsy and Ragged-red Fiber Syndrome

Myoclonus epilepsy and ragged-red fiber (MERRF) syndrome is one of the common etiologies of progressive myoclonus epilepsy. The clinical features of MERRF syndrome are myoclonus, seizure, dementia, ataxia, neuropathy, myopathy, deafness, and lipouta. The patients with MERRF syndrome have a point mutation in mitochondrial DNA at 8344 or 8356 nucleotide. We are reporting a patient who developed myoclonus and seizure at the age of eighteen. He later showed cerebellar ataxia, peripheral neuropathy, and cognitive dysfunction. Skeletal muscle biopsy failed to demonstrate ragged-red fibers. He was diagnosed as MERRF syndrome by the mitochondrial DNA analysis. He had 86% mutant mitochondrial genomes (A-)G(8%) mutation) in leukocytes, and his asymptomatic mother had 66%. The absence of ragged-red fibers does not rule out the possibility of MERRF syndrome. Demonstration of mitochondrial DNA mutation is the most convincing method for establishing the diagnosis of MERRF.

Two Cases of Lafora's Disease

Lafora's disease is one of the major causes of progressive myoclonic epilepsy. The main clinical manifestrations are epilepsy, both generalized and focal, severe and progressive myoclonus, progressive dementia and cerebellar sign, then leading to death within 2-10 years. The definite diagnosis depends on the detection of the characteristic PAS positive inclusions, which are present in various tissues including the brain, liver, muscle and skin. We presented two brothers who showed typical clinical features of this disorder, confirmed by skin and muscle biopsy.

Two Cases of Unverricht-Lundborg Disease

Unverricht-Lundborg disease(Baltic myoclonus) is one of the major causes of progressive myoclonus epilepsy. It is characterized by stimulus sensitive myoclonic seizure, generaized tonic-clonic seizure, generally synchronous polyspike and wave discharges on EEG and absence of severe or early dementia. It has usually been described in the countries around the Baltic area. But recently, it is regarded as the most common form of progressive myoclonus epilepsy in the other countries as well. We report, with the review of the literature, two patients who showed the typical features of this disorder.