Frontal ataxia: historical aspects and clinical definition / Ataxia frontal: aspectos históricos e definição clínica

Abstract Frontal ataxia, originally described by Bruns, is characterized by the presence of signs of frontal lobe dysfunction, such as perseveration, paratonia, frontal release signs, cognitive changes, and urinary difficulty, associated with imbalance, slow gait, broad-based, the presence of postural instability and falls, retropulsion, and bradykinesia in the lower limbs. The goal of the present study is to recall the historical aspects of this condition, to draw attention to the importance of this clinical finding for the differential diagnosis of ataxias and to review the main semiological differences between primary ataxias (frontal, cerebellar, and sensory ataxia).

Resumo A ataxia frontal, originalmente descrita por Bruns, caracteriza-se pela presença de sinais de disfunção do lobo frontal, como perseveração, paratonia, sinais de liberação frontal, alterações cognitivas e dificuldade urinária, associados a desequilíbrio, marcha lenta, base ampla, presença de instabilidade postural e quedas, retropulsão e bradicinesia em membros inferiores. O objetivo do presente trabalho é recordar os aspectos históricos desta condição, ressaltar a importância deste achado clínico para o diagnóstico diferencial das ataxias e revisar as principais diferenças semiológicas entre as ataxias primárias (ataxia frontal, cerebelar e sensitiva).

Ataxia telangiectasia: a diagnostic challenge. case report

ABSTRACT Introduction: Ataxia-telangiectasia (AT) is a neurodegenerative syndrome with low incidence and prevalence worldwide, which is caused by a mutation of the ATM gene. It is an autosomal recessive disorder that is associated with defective cell regeneration and DNA repair mechanisms. It is characterized by progressive cerebellar ataxia, abnormal eye movements, oculocutaneous telangiectasias and immunodeficiency. Early diagnosis is critical to initiate a timely interdisciplinary treatment, improve acute symptoms, and control the multiple comorbidities of the disease. The following is the case of a patient who presented with the aforementioned characteristics and had an adequate response to the established medical treatment. Case presentation: A 7-year-old female patient from Bogotá, who presented clinical signs of global neurodevelopmental delay, cerebellar ataxia, frequent respiratory infections and ocular telangiectasias. Symptoms were associated with elevation of alpha fetoprotein and immunodeficiency, which allowed for a diagnosis of AT and the initiation of a timely interdisciplinary treatment. Conclusion: AT is a chromosomal instability syndrome with characteristic signs and symptoms. It is essential to know the etiopathogenesis, clinical manifestations, diagnostic criteria, and therapeutic options, emphasizing that early detection and clinical suspicion could favor the proper management of the comorbidities and improve the progressive course of the disease.

RESUMEN Introducción. La ataxia-telangiectasia (AT) es un síndrome neurodegenerativo con baja incidencia y prevalencia mundial que es causado por una mutación del gen ATM, es de herencia autosómica recesiva y se asocia a mecanismos defectuosos en la regeneración y reparación del ADN. Este síndrome se caracteriza por la presencia de ataxia cerebelosa progresiva, movimientos oculares anormales, telangiectasias oculocutáneas e inmunodeficiencia. El diagnóstico oportuno de la AT es muy importante para poder iniciar un manejo interdisciplinario temprano, mejorar la sintomatología aguda y controlar las múltiples comorbilidades que causa. A continuación se presenta el caso de una paciente con las características clásicas de esta enfermedad y una adecuada respuesta y evolución al manejo médico instaurado. Presentación de caso. Paciente femenina de 7 años de edad, procedente de Bogotá, quien presentó cuadro clínico inicial de retraso global del neurodesarrollo, ataxia cerebelosa, infecciones respiratorias frecuentes y telangiectasias oculares. La sintomatología se asoció a elevación de alfa fetoproteína e inmunodeficiencia, lo que permitió plantear el diagnóstico de AT e iniciar de manera oportuna el manejo interdisciplinario. Conclusión. La AT es un síndrome de inestabilidad cromosómica con signos clínicos y síntomas característicos, por lo que es primordial conocer la etiopatogenia, el cuadro clínico, los criterios diagnósticos y las propuestas terapéuticas, pues la detección y la sospecha clínica temprana pueden favorecer el manejo precoz de las diferentes comorbilidades y mejorar el curso progresivo.

Pure-Tone Hearing Thresholds and Brainstem Auditory Evoked Potentials in Sporadic Ataxia

Abstract Introduction Spinocerebellar ataxia (SCA) is part of a genetic and clinical heteroge- neous group of neurodegenerative diseases characterized by progressive cerebellar ataxia. Objective To describe the results of audiological and electrophysiological hearing evaluations in patients with sporadic ataxia (SA). Methods A retrospective cross-sectional study was carried out with 11 patients submitted to the following procedures: anamnesis, otorhinolaryngological evaluation, tonal and vocal audiometry, acoustic immittance and brainstem auditory evoked potential (BAEP) tests. Results The patients presented with a prevalence of gait imbalance, of dysarthria, and of dysphagia; in the audiometric and BAEPs, four patients presented with alterations; in the acoustic immittance test, five patients presented with alterations, predominantly bilateral. Conclusion The most evident alterations in the audiological evaluation were the prevalence of the descending audiometric configuration between the frequencies of 2 and 4 kHz and the absence of the acoustic reflex between the frequencies of 3 and 4 kHz bilaterally. In the electrophysiological evaluation, the patients presented changes with a prevalence of increased I, III and V wave latencies and the interval in the interpeak I-III, I-V and III-V. In the present study, it was observed that auditory complaints did not have a significant prevalence in this type of ataxia, which does not occur in some types of autosomal recessive and dominant ataxia.

Twenty-five years since the identification of the first SCA gene: history, clinical features and perspectives for SCA1 / Vinte e cinco anos desde a identificação do primeiro gene das SCAs: história, aspectos clínicos e perspectivas para a SCA1

ABSTRACT Spinocerebellar ataxias (SCA) are a clinically and genetically heterogeneous group of monogenic diseases that share ataxia and autosomal dominant inheritance as the core features. An important proportion of SCAs are caused by CAG trinucleotide repeat expansions in the coding region of different genes. In addition to genetic heterogeneity, clinical features transcend motor symptoms, including cognitive, electrophysiological and imaging aspects. Despite all the progress in the past 25 years, the mechanisms that determine how neuronal death is mediated by these unstable expansions are still unclear. The aim of this article is to review, from an historical point of view, the first CAG-related ataxia to be genetically described: SCA 1.

RESUMO As ataxias espinocerebelares (SCA) são um grupo clínico e geneticamente heterogêneo de doenças monogênicas que compartilham ataxia e herança autossômica dominante como características principais. Uma proporção importante de SCAs é causada por expansões de repetição de trinucleotídeos CAG na região de codificação de diferentes genes. Além da heterogeneidade genética, os aspectos clínicos transcendem os sintomas motores, incluindo aspectos cognitivos, eletrofisiológicos e de imagem. Apesar de todo o progresso feito nos últimos 25 anos, os mecanismos que determinam como se dá a morte neuronal mediada por essas expansões instáveis ainda não estão claros. O objetivo deste artigo é revisar, de um ponto de vista histórico, a primeira ataxia geneticamente relacionada com o CAG descrita: SCA 1.

The importance of central auditory evaluation in Friedreich's ataxia / A importância da avaliação auditiva central na ataxia de Friedreich

ABSTRACT Objective To assess central auditory function in Friedreich's ataxia. Methods A cross-sectional, retrospective study was carried out. Thirty patients underwent the anamnesis, otorhinolaryngology examination, pure tone audiometry, acoustic immittance measures and brainstem auditory evoked potential (BAEP) assessments. Results The observed alterations were: 43.3% in the pure tone audiometry, bilateral in 36.7%; 56.6% in the BAEP test, bilateral in 50%; and 46.6% in the acoustic immittance test. There was a significant difference (p < 0.05) in the comparison between the tests performed. Conclusion In the audiological screening, there was a prevalence of the descending audiometric configuration at the frequency of 4kHz, and absence of the acoustic reflex at the same frequency. In the BAEP test, there was a prevalence of an increase of the latencies in waves I, III and V, and in the intervals of interpeaks I-III, I-V and III-V. In 13.3% of the patients, wave V was absent, and all waves were absent in 3.3% of patients.

RESUMO Objetivo Avaliar a função auditiva central na ataxia de Friedreich (AFRD). Métodos Foi realizado um estudo retrospectivo de corte transversal. 30 pacientes realizaram anamnese, avaliações otorrinolaringológica, audiológica, imitanciométrica e do potencial evocado auditivo de tronco encefálico (PEATE). Resultados As alterações observadas foram: 43,3% no exame audiométrico sendo 36,7% dos casos, bilateralmente; 56,6% na avaliação do PEATE com 50% dos casos, bilateralmente e 46,6% no exame imitanciométrico. Houve diferença significativa (p < 0,05) na comparação entre os exames realizados. Conclusão No exame audiológico, ocorreu uma preponderância maior da configuração audiométrica descendente a partir da freqüência de 4kHz e ausência do reflexo acústico na mesma frequência. No exame do PEATE, houve prevalência do aumento das latências nas ondas I, III e V, e nos intervalos dos interpicos I-III, I-V e III-V. Em 13,3% dos casos, a onda V estava ausente, e em 3,3% dos casos, todas as ondas estavam ausentes.

Novel compound heterozygous mutations of ATM in ataxia-telangiectasia: A case report and calculated prevalence in the Republic of Korea

Ataxia-telangiectasia (AT; OMIM 208900) is a rare autosomal recessive inherited progressive neurodegenerative disorder, with onset in early childhood. AT is caused by homozygous or compound heterozygous mutations in ATM (OMIM 607585) on chromosome 11q22. The average prevalence of the disease is estimated at 1 of 100,000 children worldwide. The prevalence of AT in the Republic of Korea is suggested to be extremely low, with only a few cases genetically confirmed thus far. Herein, we report a 5-year-old Korean boy with clinical features such as progressive gait and truncal ataxia, both ankle spasticity, dysarthria, and mild intellectual disability. The patient was identified as a compound heterozygote with two novel genetic variants: a paternally derived c.5288_5289insGA p.(Tyr1763*) nonsense variant and a maternally derived c.8363A>C p.(His2788Pro) missense variant, as revealed by next-generation sequencing and confirmed by Sanger sequencing. Based on claims data from the Health Insurance Review and Assessment Service Republic of Korea, we calculated the prevalence of AT in the Republic of Korea to be about 0.9 per million individuals, which is similar to the worldwide average. Therefore, we suggest that multi-gene panel sequencing including ATM should be considered early diagnosis.

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.

Otoneurological Abnormalities in Patients with Friedreich's Ataxia

Abstract Introduction Friedreich's ataxia is a neurodegenerative disease and progressive by nature. It has autosomal recessive inheritance and early onset inmost cases. Nystagmus and hearing loss (in some cases) make up some of the common symptoms seen in this disorder. Objective The objective of this study is to examine vestibular disorders in patientswith Friedreich ataxia. Methods We conducted a retrospective cross-sectional study. We evaluated 30 patients with ages ranging from six to 72 years (mean age of 38.6 ( 14.7). The patients underwent the following procedures: anamnesis, ENT, and vestibular evaluations. Results Clinically, the patients commonly had symptoms of incoordination of movement (66.7%), gait disturbances (56.7%), and dizziness (50%). In vestibular testing, alterations were predominantly evident under caloric testing (73.4%), gaze nystagmus testing (50.1%), rotational chair testing (36.7%), and optokinetic nystagmus testing (33.4%). The presence of alterations occurred under examination in 90% of subjects, with the majority occurring in those with central vestibular dysfunction (70% of the examinations). Conclusion The most evident neurotological symptoms were incoordination of movement, gait disturbances, and dizziness. Alterations in vestibular examinations occurred in 90% of patients, mostly in the caloric test, with a predominance of deficient central vestibular system dysfunction.

Novel spastic ataxia of Charlevoix-Saguenay gene compound heterozygous mutations in late onset autosomal recessive spastic ataxia of Charlevoix-Saguenay / 中华神经科杂志

Objective To investigate the clinical features and laboratory results in a patient with late onset autosomal recessive spastic ataxia of Charlevoix-Saguenay ( ARSACS ) carrying novel SACS ( spastic ataxia of Charlevoix-Saguenay ) gene heterozygous mutations .Methods A 26-year-old Chinese man developed since the age of 13 a progressive weakness and stiffness of his bilateral lower limbs and gait unsteadiness.He had pyramidal tract sign in his bilateral lower limbs , cerebellar ataxia and sensory-motor polyneuropathy , with hyperelastica and swan neck-like deformities of the fingers , pes cavus and hammer toes.Funduscopy and optical coherence tomography , brain and cervical MRI , conduction velocity of peripheral nerve , motor evoked potentials , visual and brainstem auditory evoked potentials , ultrasound of peripheral nerve , hips and legs MRI , electronystagmography , and targeted capture and next generation sequencing were performed .Results Funduscopy and optical coherence tomography revealed thickening of the retinal nerve fiber layer with unclear margined optic disc .MRI revealed symmetrical linear hypointensity lesions in the pons on T 2 and T2 FLAIR weighted images , thickened bilateral cerebellar peduncles , and flattened and atrophied cervical and upper thoracic spinal cord .Nerve conduction studies showed sensory nerve action potentials were absent in four limbs , motor conduction velocity was slowed , amplitude of muscle response was significantly decreased in lower-limb nerves ( decreased by 80% -100%) but normal in upper-limb nerves.Central motor conduction time of motor evoked potential was prolonged .Targeted capture and next generation sequencing revealed novel SACS compound heterozygous mutations , c.12637 _12638delGA (p.Glu4213ArgFs*3) and c.11274_11276delAAC (p.Ile3758_Thr3759delinsMet) derived from each parent respectively , which were confirmed by Sanger sequencing analyses . Conclusions Recognizing ARSACS triad and its characteristics on fundus and brain MRI is helpful for correct diagnosis . Our findings expand the clinical and genetic spectrum of ARSACS .

Ataxia espinocerebelar tipo 6: relato de caso / Spinocerebellar ataxia type 6: a case report

O objetivo deste estudo foi verificar as alterações vestibulococleares observadas em um caso de ataxia espinocerebelar tipo 6. O caso foi encaminhado do Hospital de Clínicas para o Laboratório de Otoneurologia de uma Instituição de Ensino e foi submetido aos seguintes procedimentos: anamnese, inspeção otológica, avaliações audiológica e vestibular. O caso retrata uma paciente com diagnóstico genético de ataxia espinocerebelar tipo 6, do sexo feminino, com 57 anos de idade, que referiu desequilíbrio à marcha com tendência a queda para a esquerda, disartria e disfonia. Na avaliação audiológica apresentou configuração audiométrica descendente a partir da frequência de 4kHz e curva timpanométrica do tipo "A" com presença dos reflexos estapedianos bilateralmente. No exame vestibular observou-se na pesquisa da vertigem posicional presença de nistagmo vertical inferior e oblíquo, espontâneo e semiespontâneo múltiplo com características centrais (ausência de latência, paroxismo, fatigabilidade e vertigem), nistagmooptocinético abolido e hiporreflexia à prova calórica. Constataram-se alterações labirínticas que indicaram afecção do sistema vestibular central evidenciando-se a importância dessa avaliação. A existência da possível relação entre os achados com os sintomas vestibulares apresentados pela paciente apontou a relevância do exame labiríntico neste tipo de ataxia uma vez que a presença do nistagmo vertical inferior demonstrou ser frequente neste tipo de patologia.

The aim of this study was to investigate the vestibulocochlear alterations observed in a case of spinocerebellar ataxia type 6. The case was referred from the Hospital das Clinicas to the Otoneurology Laboratory of an educational institution and was subjected to the following procedures: anamnesis, otologic examination, as well as audiological and vestibular assessments. The case shows a 57-year-old female patient with a genetic diagnosis of spinocerebellar ataxia type 6 who presented unsteadiness of gait with tendency to fall to the left, dysarthria, and dysphonia. The audiological assessment presented sloping audiometric configuration from 4.0 kHz and tympanogram type “A” with the presence of acoustic reflexes bilaterally. Observed during the survey of positional vertigo in the vestibular assessment were the presence of oblique and vertical downbeat nystagmus, spontaneous and semispontaneous with multiple core features (absence of latency, paroxysm, fatigue and vertigo), abolished optokineticnystagmus and hyporeflexia in the caloric test. We found labyrinthic alterations that indicate central vestibular system disorders and lend credence to the importance of this evaluation. The existence of a possible relationship between the findings and vestibular symptoms displayed by the patient indicated the relevance of the labyrinthine evaluation for this type of ataxia once the presence of vertical downbeat nystagmus proved to be frequent in this type of pathology.

Reabilitação vestibular com realidade virtual na ataxia espinocerebelar / Vestibular rehabilitation with virtual reality in spinocerebellar ataxia

O objetivo do estudo foi verificar os benefícios da reabilitação vestibular (RV) com realidade virtual, por meio de avaliação pré e pós-aplicação da Escala de Equilíbrio de Berg (EEB), em quatro casos de ataxia espinocerebelar (AEC). Os casos foram submetidos aos seguintes procedimentos: anamnese, inspeção otológica, avaliação vestibular e aplicação da EEB pré e pós-RV, com a realidade virtual representada por meio da utilização de jogos do equipamento Wii Fit. Os casos retratam quatro pacientes com diagnóstico genético de AEC (dois tipo 2, um tipo 3 e um em investigação), sendo três do gênero feminino e um do gênero masculino, na faixa etária de 30 a 62 anos. Os pacientes referiram sintomas otoneurológicos e, no exame vestibular, observou-se a presença de nistagmo semiespontâneo com características centrais, ausência de nistagmo pós-rotatório, hiporreflexia e preponderância direcional do nistagmo assimétrica à prova calórica. Nos casos 1 e 2, os pacientes referiram melhora na coordenação dos movimentos e do equilíbrio corporal, independente do escore na EEB ter demonstrado médio risco para queda, antes e após a realização dos exercícios. No caso 3, o paciente apresentou melhora do escore na EEB, bem como do equilíbrio, apresentando baixo risco para queda. O caso 4 não evidenciou melhora na avaliação após a execução dos exercícios. Este estudo de caso demonstrou a possibilidade da aplicação dos exercícios de RV com estímulos virtuais na AEC, com melhora da coordenação motora e do equilíbrio postural.

The purpose of this study was to verify the benefits of the vestibular rehabilitation (VR) with virtual reality through the assessment before and after the application of the Berg Balance Scale (BBS) in four cases of spinocerebellar ataxia (SCA). The cases were underwent the following procedures: anamnesis, ear inspection, vestibular assessment and application of the BBS before and after VR with virtual reality using games from Wii Fit device. The cases describe four patients that were diagnosed with genetically inherited SCA (two type 2, one type 3 and one still under investigation), three of them were female and one was male, with ages ranging from 30 to 62 years. The patients presented otoneurological symptoms and the vestibular test showed the presence of semi-spontaneous nystagmus, absence of post-rotational nystagmus, hyporeflexia, and asymmetric directional preponderance of the nystagmus in the caloric test. Patients from cases 1 and 2 have showed an improvement in motor coordination and in body balance, even though the score presented by the BBS had demonstrated medium risk for falling before and after the exercises. In case 3, the patient's loss of balance and BBS score have improved, presenting low risk of falling; whereas the patient in case 4 did not show any improvement in the assessment after the exercises. This case study shows the applicability of VR exercises with virtual stimuli in SCA with improved motor coordination and postural balance.

Avaliação audiológica na ataxia espinocerebelar / Audiological evaluation in spinocerebellar ataxia

OBJETIVO: Descrever os resultados das avaliações audiológica e eletrofisiológica da audição em pacientes portadores de ataxia espinocerebelar (AEC). MÉTODOS: Foi realizado um estudo retrospectivo de corte transversal no qual se avaliou 43 pacientes portadores de AEC submetidos aos seguintes procedimentos: anamnese e avaliações otorrinolaringológica, audiológica, imitanciométrica e do potencial evocado auditivo de tronco encefálico (PEATE). RESULTADOS: Os pacientes apresentaram prevalência do desequilíbrio à marcha (83,7%), dificuldade para falar (48,8%), tontura (41,8%) e disfagia (39,5%). A perda auditiva foi referida em 27,9% dos casos; no exame audiométrico, 14 pacientes (32,5%) apresentaram alterações; na AEC 3, 33,3%; na AEC 2, 12,5%; na AEC 4, 100,0%; na AEC 6, 100,0%; na AEC 7, 100,0%; na AEC 10, 50,0%; e na AEC indeterminada, 21,4%. No PEATE, 20 pacientes (46,5%) apresentaram alterações, sendo 58,3% na AEC 3, 62,5% na AEC 2, 100,0% na AEC 6, 100,0% na AEC 7, 66,7% na AEC 10 e 14,2% na AEC indeterminada. No exame imitanciométrico, 19 pacientes (44,1%) apresentaram alterações, sendo 50,0% na AEC 3, 50,0% na AEC 2, 100,0% na AEC 4, 100,0% na AEC 6, 100,0% na AEC 7, 33,3% na AEC 10 e 28,5% na AEC indeterminada. CONCLUSÃO: As alterações mais evidenciadas na avaliação audiológica foram o predomínio da configuração audiométrica descendente a partir da frequência de 4 kHz bilateralmente e a ausência do reflexo acústico nas frequências de 3 e 4 kHz bilateralmente. Na avaliação eletrofisiológica, 50% dos pacientes apresentaram alterações com prevalência do aumento das latências das ondas I, III e V e do intervalo nos interpicos I-III, I-V e III-V.

PURPOSE: To describe the audiological and electrophysiological results in patients with spinocerebellar ataxia (SCA). METHODS: Retrospective and cross-sectional studies were performed. Forty-three patients were assessed using the following procedures: anamnesis and otolaryngologic exam, pure tone audiometry, acoustic immittance measures and brainstem auditory evoked potential (BAEP). RESULTS: Patients showed gait abnormality (83.7%), speech disorder (48.8%), dizziness (41.8%) and dysphagia (39.5%). Hearing loss was referred in 27.9% of the cases; in the audiometric exams, 14 patients (32.5%) presented disorders; in SCA 3, 33.3%; in SCA 2, 12.5%; in SCA 4, 100.0%; in SCA 6, 100.0%; in SCA 7, 100.0%; in SCA 10, 50.0%; and in undetermined SCA, 21.4%. In BAEP, 20 patients (46.5%) were abnormal, being 58.3% in SCA 3, 62.5% in SCA 2, 100.0% in SCA 6, 100.0% in SCA 7, 66.7% in SCA 10 and 14.2% in undetermined SCA. While in acoustic immittance, 19 patients (44.1%) presented disorders, being 50.0% in SCA 3, 50.0% in SCA 2, 100.0% in SCA 4, 100.0% in SCA 6, 100.0% in SCA 7, 33.3% in SCA 10 and 28.5% in undetermined SCA. CONCLUSION: The most evident abnormalities in the audiological evaluation were the predominance of the down-sloping audiometric configuration beginning at 4 kHz bilaterally and the bilateral absence of acoustic reflex at the frequencies of 3 and 4 kHz. In the electrophysiological evaluation, 50% of the patients showed abnormalities with prevalence of an increase of the latency of waves I, II and V and of the interval in the interpeaks I-III, I-V and III-V.

Ataxia espinocerebelar tipo 7 / Spinocerebellar ataxia type 7

O objetivo deste estudo foi verificar possíveis alterações vestibulococleares em um caso de ataxia espinocerebelar tipo 7. O paciente foi encaminhado para o Laboratório de Otoneurologia da Universidade Tuiuti do Paraná e foi submetido aos seguintes procedimentos: anamnese, inspeção otológica, avaliações audiológica e vestibular. Trata-se de indivíduo do gênero feminino, de 34 anos de idade, com diagnóstico genético de ataxia espinocerebelar tipo 7, que referiu desequilíbrio à marcha, dificuldade para falar, cefaléia, tontura e disfagia. Em avaliação audiológica, apresentou limiares auditivos dentro dos padrões de normalidade e curva timpanométrica do tipo "A" com presença dos reflexos estapedianos bilateralmente. No exame vestibular, observou-se presença de nistagmos espontâneo e semi-espontâneo com características centrais, nistagmo optocinético e rastreio pendular alterados e hiperreflexia à prova calórica. Constatamos alterações labirínticas que indicam afecção do sistema vestibular central e evidenciam a importância dessa avaliação. A existência da possível relação entre os achados com os sintomas otoneurológicos apresentados pela paciente nos remete a uma nova questão, ou seja, à importância da aplicabilidade dos exercícios de reabilitação que atuam em estruturas centrais de neuroplasticidade. Eles aceleram e estimulam mecanismos naturais de compensação, que poderão proporcionar ao portador de ataxia um melhor desempenho de suas funções.

The aim of this study was to verify the possible alterations observed in a case of spinocerebellar ataxia type 7. The patient was referred to the Laboratory of Neurotology of Universidade Tuiuti do Paraná (Brazil), and was submitted to the following procedures: anamnesis, otoscopy, auditory and vestibular assessments. The case described is a 34-year-old woman with a genetic diagnosis of spinocerebellar ataxia type 7, who referred imbalance when walking, speech difficulties, headache, dizziness, and dysphagia. The audiological evaluation showed normal hearing thresholds and tympanometric curve type "A", with bilateral presence of stapedius reflex. In the vestibular evaluation, it was observed the presence of spontaneous and gaze nystagmus with central characteristics, altered optokinetic nystagmus and pendular tracking, and hyperreflexia during the caloric test. Labyrinth alterations were found, indicating central vestibular system affection and evidencing the importance of this evaluation. The existence of a possible relationship between the findings and the neurotological symptoms presented by the patient leads us to a new issue, that is, the importance of the applicability of rehabilitation exercises that act in central structures of neuroplasticity. These exercises accelerate and stimulate natural compensation mechanisms, which may provide the patient with ataxia a better performance of its functions.

Contribuição para a caracterização clínica das ataxias hereditárias autossômicas recessivas / Contribution to clinical characterization of autosomal recessive hereditary ataxias

As ataxias hereditárias autossômicas recessivas compõem um grupo de doenças heterogêneas, que necessitam de criteriosa avaliação clínica, de exames complementares e, algumas vezes, de testes genéticos para o diagnóstico. A partir da revisão da literatura, foi elaborado um algoritmo para auxiliar a investigação diagnóstica deste grupo. Esta tese tem como objetivo apresentar os resultados da investigação de três formas de ataxias recessivas: 1. Síndrome de Joubert, caracterizada por hipotonia precoce, atraso do desenvolvimento neuropsicomotor, ataxia e padrão respiratório irregular no período neonatal ou anormalidades na motricidade ocular extrínseca. Apresenta amplo espectro clínico, assim como heterogeneidade genética. Alterações renal, hepática e da retina são frequentes. A presença de hipoplasia do vermis cerebelar, alongamento dos pedúnculos cerebelares superiores e aumento da fossa interpeduncular, aos cortes axiais da ressonância magnética (RM) do encéfalo, constituem o sinal do dente molar, considerado critério radiológico obrigatório para o diagnóstico. Aqui é apresentada uma série de cinco pacientes que preenchem critérios clínicos e radiológico de síndrome de Joubert e tem grande variabilidade fenotípica: duas crianças têm a forma pura (subtipo 1), uma tem associadamente retinopatia (subtipo 3), uma tem amaurose congênita de Leber e alteração renal (subtipo 4) e a outra apresenta associadamente coloboma corioretiniano e alterações hepáticas (subtipo 5); 2. Ataxia com Deficiência de Vitamina E, que apresenta fenótipo semelhante ao da ataxia de Friedreich, progressão mais lenta, baixo nível sérico de -tocoferol e é tratável com reposição da vitamina E. Frequente no sul da Itália e norte da África, sem relatos no Brasil. Foram investigados quatro pacientes pertencentes a duas famílias: três apresentavam o quadro clínico típico acompanhado de distonia em mãos, manifestação pouco relatada, mas que pode contribuir para a diferenciação clínica...

Autosomal recessive hereditary ataxias belong to a group of heterogeneous disorders, for which detailed clinical evaluation, ancillary exams, and sometimes, genetic tests, are required for diagnosis. After literature review, an algorithm was built to help the investigation of this group. The objective of this thesis is to present the results of investigation of three forms of recessive ataxias: 1. Joubert syndrome is a condition characterized by early hypotonia, developmental delay, ataxia and neonatal respiratory disturbances or abnormal eye movement. It has a wide clinical spectrum and is genetically heterogeneous. Renal, hepatic and retina abnormalities are often seen. A combination of midline cerebellar vermis hypoplasia, deepened interpenducular fossa, and thick, elongated superior cerebellar penduncles gives to the axial view of the midbrain an appearance of a molar tooth at brain magnetic ressonance image (MRI) study. Molar tooth sign is considered as obligatory radiologic criteria to diagnosis. In this study we present a series of five patients that have clinical and radiologic criteria to Joubert syndrome and a large phenotypic variability: Two children have a pure form (subgroup 1), one child has an associated retinopathy (subgroup 3), the other has Leber congenital amaurosis and kidney abnormalitties (subgroup 4), and another has chorioretinal coloboma and hepatic abnormalities (subgroup 5); 2. Ataxia with vitamin E deficiency, which has a phenotype similar to Friederich ataxia but slowest progression, is characterized by low levels of serum -tocopherol and is treatable with vitamin E. This ataxia is common in South Italy and North Africa, but was not reported in Brazil. Four patients from two different families were studied. Three of them have typical clinical features and hands dystonia, a probably underreported feature which might helps its distinction from Friedreich ataxia. The other case was identified in a presymptomatic stage, after...

Chronological changes of pathology in cerebellar degeneration in rats with methylmercury induced toxication / 第二军医大学学报

Objective:To explore the pathology and pathogenesis of cerebellar injuries induced by methylmercury chloride(MMC) toxication in rats. Methods:Rats were given MMC(4 mg·kg-1·d-1) consecutively and sacrificed on days 11, 15, 18 and 21. Pathological changes of the cerebellum were observed by histo-immunopathology; in situ staining was performed for DNA strand breaks in cerebellar granule cells by TUNEL technique; and the ultrastructures were observed by electron microscope. Results:On day 18, sparse TUNEL positive granular cells were observed mainly in deep lamina adjacent to the white matter. On day 21, apoptotic cells markedly increased and granule cells decreased with well-preserved Purkinje cells. Immunostaining with MRF-1 and GFAP demonstrated severe microgliosis and astrocytosis. On day 18, electron microscopy demonstrated that the nuclei of MMC-treated animals were shrunken and displayed increased electron density, and some homogeneously dense nuclear chromatin with tear-drop features, which were compatible with the apoptotic changes. Conclusion:These results indicate that the pathological changes in the cerebellum in this subacute MMC intoxication model resemble human cases, and the degeneration of granule cells is apoptosis.

Chronological changes of pathology in cerebellar degeneration in rats with methylmercury induced toxication / 第二军医大学学报

Objective:To explore the pathology and pathogenesis of cerebellar injuries induced by methylmercury chloride(MMC) toxication in rats. Methods:Rats were given MMC(4 mg·kg-1·d-1) consecutively and sacrificed on days 11, 15, 18 and 21. Pathological changes of the cerebellum were observed by histo-immunopathology; in situ staining was performed for DNA strand breaks in cerebellar granule cells by TUNEL technique; and the ultrastructures were observed by electron microscope. Results:On day 18, sparse TUNEL positive granular cells were observed mainly in deep lamina adjacent to the white matter. On day 21, apoptotic cells markedly increased and granule cells decreased with well-preserved Purkinje cells. Immunostaining with MRF-1 and GFAP demonstrated severe microgliosis and astrocytosis. On day 18, electron microscopy demonstrated that the nuclei of MMC-treated animals were shrunken and displayed increased electron density, and some homogeneously dense nuclear chromatin with tear-drop features, which were compatible with the apoptotic changes. Conclusion:These results indicate that the pathological changes in the cerebellum in this subacute MMC intoxication model resemble human cases, and the degeneration of granule cells is apoptosis.