-Spinocerebellar ataxias (SCAs) constitute a heterogeneous group of neurodegenerative diseases characterized by progressive cerebellar ataxia in association with some or all of the following conditions: ophthalmoplegia, pyramidal signs, movement disorders, pigmentary retinopathy, peripheral neuropathy, cognitive dysfunction and dementia. Objective: To carry out a clinical and genetic review of the main types of SCA. Method: The review was based on a search of the PUBMED and OMIM databases. Results: Thirty types of SCAs are currently known, and 16 genes associated with the disease have been identified. The most common types are SCA type 3, or Machado-Joseph disease, SCA type 10 and SCA types 7, 2, 1 and 6. SCAs are genotypically and phenotypically very heterogeneous. A clinical algorithm can be used to distinguish between the different types of SCAs. Conclusions: Detailed clinical neurological examination of SCA patients can be of great help when assessing them, and the information thus gained can be used in an algorithm to screen patients before molecular tests to investigate the correct etiology of the disease are requested.KEY WORDS: spinocerebellar ataxias, cerebellar atrophy, genotype, phenotype. Ataxias espinocerebelaresResumo -As ataxias espinocerebelares (AECs) compreendem um grupo heterogeneo de enfermidades neurodegenerativas, que se caracterizam pela presença de ataxia cerebelar progressiva, associada de forma variada com oftalmoplegia, sinais piramidais, distúrbios do movimento, retinopatia pigmentar, neuropatia periférica, disfunção cognitiva e demência. Objetivo: Realizar uma revisão clínico-genética dos principais tipos de AECs. Método: A revisão foi realizada através da pesquisa pelo sistema do PUBMED e do OMIM. Resultados: Na atualidade existem cerca de 30 tipos de AECs, com a descoberta de 16 genes. Os tipos mais comuns são a AEC tipo 3, ou doença de Machado-Joseph, a AEC tipo 10, e as AECs tipo 7, 2 1, e 6. As AECs apresentam grande heterogeneidade genotípica e fenotípica. Pode-se utilizar um algoritmo clínico para a pesquisa dos diferentes tipos de AECs. Conclusões: O exame clínico neurológico minucioso nos pacientes com AECs pode auxiliar sobremaneira na avaliação clínica destes pacientes, utilizando-se desta forma de um algoritmo, com os dados clínicos, que pode servir como um instrumento de triagem para a solicitação dos testes de genética molecular, para a correta investigação etiológica.

Knowledge of primary ataxias has been growing rapidly in recent years. Here we review different forms of primary ataxia, including inherited forms, which are subdivided into congenital, autosomal recessive cerebellar ataxias, autosomal dominant cerebellar ataxias, episodic ataxias, X-linked ataxias, and mitochondrial ataxias, as well as sporadic ataxias and idiopathic degenerative ataxias. Secondary or acquired ataxias are also reviewed and the most common causes are discussed.

Spinocerebellar ataxia type 3 or Machado-Joseph disease is the most common spinocerebellar ataxia worldwide, and the high frequency of nonmotor manifestations in Machado-Joseph disease demonstrates how variable is the clinical expression of this single genetic entity. Anatomical, physiological, clinical, and functional neuroimaging data reinforce the idea of a degenerative process involving extracerebellar regions of the nervous system in Machado-Joseph disease. Brain imaging and neuropathologic studies have revealed atrophy of the pons, basal ganglia, midbrain, medulla oblongata, multiple cranial nerve nuclei, and thalamus and of the frontal, parietal, temporal, occipital, and limbic lobes. This review provides relevant information about nonmotor manifestations and extracerebellar symptoms in Machado-Joseph disease. The main nonmotor manifestations of Machado-Joseph disease described in previous data and discussed in this article are: sleep disorders, cognitive and affective disturbances, psychiatric symptoms, olfactory dysfunction, peripheral neuropathy, pain, cramps, fatigue, nutritional problems, and dysautonomia. In addition, we conducted a brief discussion of noncerebellar motor manifestations, highlighting movement disorders. © 2013 Movement Disorder Society.

OBJECTIVE:Spinocerebellar ataxias are neurodegenerative disorders involving the cerebellum and its connections. There are more than 30 distinct subtypes, 16 of which are associated with an identified gene. The aim of the current study was to evaluate a large group of patients from 104 Brazilian families with spinocerebellar ataxias.METHODS:We studied 150 patients from 104 families with spinocerebellar ataxias who had received molecular genetic testing for spinocerebellar ataxia types 1, 2, 3, 6, 7, 8, 10, 12, 17, and dentatorubral-pallidoluysian atrophy. A statistical analysis of the results was performed using basic descriptive statistics and the correlation coefficient (r), Student's t-test, chi-square test, and Yates' correction. The statistical significance level was established for p-values <0.05.RESULTS:The results show that the most common subtype was spinocerebellar ataxia 3, which was followed by spinocerebellar ataxia 10. Moreover, the comparison between patients with spinocerebellar ataxia 3, spinocerebellar ataxia 10, and other types of spinocerebellar ataxia revealed distinct clinical features for each type. In patients with spinocerebellar ataxia 3, the phenotype was highly pleomorphic, although the most common signs of disease included cerebellar ataxia (CA), ophthalmoplegia, diplopia, eyelid retraction, facial fasciculation, pyramidal signs, and peripheral neuropathy. In patients with spinocerebellar ataxia 10, the phenotype was also rather distinct and consisted of pure cerebellar ataxia and abnormal saccadic eye movement as well as ocular dysmetria. Patients with spinocerebellar ataxias 2 and 7 presented highly suggestive features of cerebellar ataxia, including slow saccadic ocular movements and areflexia in spinocerebellar ataxia 2 and visual loss in spinocerebellar ataxia 7.CONCLUSIONS:Spinocerebellar ataxia 3 was the most common subtype examined, followed by spinocerebellar ataxia 10. Patients with spinocerebellar ataxia 2 and 7 demonstrated highly suggestive features, whereas the phenotype of spinocerebellar ataxia 3 patients was highly pleomorphic and spinocerebellar ataxia 10 patients exhibited pure cerebellar ataxia. Epilepsy was absent in all of the patients with spinocerebellar ataxia 10 in this series.

Charcot e o Brasil RESUMO -

Introduction Nonmotor symptoms (NMS) have been described in several neurodegenerative diseases but have not been systematically evaluated in spinocerebellar ataxia type 10 (SCA10). Objective To compare the frequency of NMS in patients with SCA10, Machado-Joseph disease (MJD) and healthy controls. Methods Twenty-eight SCA10, 28 MJD and 28 healthy subjects were prospectively assessed using validated screening tools for chronic pain, autonomic symptoms, fatigue, sleep disturbances, psychiatric disorders, and cognitive function. Results Chronic pain was present with similar prevalence among SCA10 patients and healthy controls, but was more frequent in MJD. Similarly, autonomic symptoms were found in SCA10 in the same proportion of healthy individuals, while the MJD group had higher frequencies. Restless legs syndrome and REM sleep behavior disorder were uncommon in SCA10. The mean scores of excessive daytime sleepiness were worse in SCA10 group. Scores of fatigue were higher in the SCA10 sample compared to healthy individuals, but better than in the MJD. Psychiatric disorders were generally more prevalent in both spinocerebellar ataxias than among healthy controls. The cognitive performance of healthy controls was better compared with SCA10 patients and MJD, which showed the worst scores. Conclusions Although NMS were present among SCA10 patients in a higher proportion compared to healthy controls, they were more frequent and severe in MJD. In spite of these comparisons, we were able to identify NMS with significant functional impact in patients with SCA10, indicating the need for their systematic screening aiming at optimal treatment and improvement in quality of life.

Lafora disease is characterized by pathognomonic inclusions, Lafora bodies (LB), in neurons and other cell types. In skin, LB have been reported in either eccrine sweat glands or in apocrine sweat glands. The disease is caused by mutations in either the EPM2A gene or in a second yet-unknown gene. Here the authors determine whether a genotype-phenotype correlation exists between the genetic form of the disease and the skin cell type affected by LB formation. Also is described an important source of false positivity in the use of axillary biopsies for disease diagnosis.

Spinocerebellar ataxia type 3 (SCA3) involves cerebellar, pyramidal, extrapyramidal, motor neuron and oculomotor systems with strong phenotypic heterogeneity, that lead us to classify the disorder into different clinical subtypes according to the predominantly affected motor systems. Method: The series comprises 167 SCA3 patients belonging to 68 pedigrees, studied from 1989-2013. These patients were categorized into seven different subphenotypes. Results: SCA3 cases were clustered according to the predominant clinical features. Three most common forms were subphenotype 2, characterized by ataxia and pyramidal symptom was observed in 67.5%, subphenotype 3 with ataxia and peripheral signs in 13.3%, and subphenotype 6 with pure cerebellar syndrome in 7.2%. Conclusion: Our study was the first to systematically classify SCA3 into seven subphenotypes. This classification may be particularly useful for determination of a more specific and direct phenotype/genotype correlation in future studies.Keywords: Machado-Joseph disease, subphenotypes, spinocerebellar ataxia type 3. RESUMOA ataxia espinocerebelar do tipo 3 (AEC3) envolve os sistemas cerebelar, piramidal, extrapiramidal, do neurônio motor e oculomotor, com uma grande heterogeneidade fenotípica, o que nos levou a classificar essa desordem em diferentes subtipos clínicos de acordo com o sistema predominantemente afetado. Método: Nossa série compreende 167 pacientes com AEC3, pertencentes a 68 famílias, avaliados de 1989 a 2013. Esses pacientes foram classificados em 7 diferentes subtipos. Resultados: Os pacientes com AEC3 foram agrupados de acordo com as características clínicas predominantes. As três formas mais comum foram o subfenótipo 2, caracterizado por ataxia e sintomas piramidais, observado em 67,5% dos pacientes, subfenótipo 3 com ataxia e sinais periféricos, em 13,3%, e subfenótipo 6 com síndrome cerebelar pura, em 7,2%. Conclusão: Nosso estudo foi o primeiro a classificar sistematicamente AEC3 em sete subtipos. Esta classificação pode ser particularmente útil para correlacionar fenótipo/genótipo com mais especificidade em futuros estudos.Palavras-chave: doença de Machado-Joseph, subfenótipos, ataxia espinocerebelar tipo 3.