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Publications (4)14.25 Total impact

  • Article: Mutations in SACS cause atypical and late-onset forms of ARSACS.
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    ABSTRACT: Autosomal recessive spastic ataxia of Charlevoix-Saguenay (ARSACS) is a complex neurodegenerative disorder caused by mutations in SACS. The phenotype consists of a childhood-onset triad of cerebellar ataxia, peripheral neuropathy, and pyramidal tract signs. To provide more insight into the prevalence of SACS mutations and the variability of the associated phenotype. Mutation screening of SACS by direct sequencing and multiplex amplicon quantification for detection of intragenic copy number variations in a cohort of 85 index patients with phenotypes suggestive for ARSACS. Additional short tandem repeat (STR) marker analysis was performed for haplotype sharing. In 11 families,18 new SACS mutations were found (12.9% of total cohort). Five patients displayed onset ages in adulthood, a feature not known to be associated with ARSACS. The remaining index patients displayed a classic early onset phenotype. Initial phenotypic presentation was atypical in several patients, obscuring the clinical diagnosis. A founder mutation in SACS was identified in 3 Belgian families. In one isolated patient, an intragenic SACS deletion of exons 3-5 was detected. Partial SACS deletions were not previously described. In this study, we enlarge the ARSACS phenotype and the underlying genetic spectrum of SACS mutations. Patients with ARSACS are more common than previously known and risk underdiagnosis due to late onset age and unusual presentation.
    Neurology 09/2010; 75(13):1181-8. · 8.31 Impact Factor
  • Article: Progressive myoclonic epilepsy as an adult-onset manifestation of Leigh syndrome due to m.14487T>C.
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    ABSTRACT: m.14487T>C, a missense mutation (p.M63V) affecting the ND6 subunit of complex I of the mitochondrial respiratory chain, has been reported in isolated childhood cases with Leigh syndrome (LS) and progressive dystonia. Adult-onset phenotypes have not been reported. To determine the clinical-neurological spectrum and associated mutation loads in an extended m.14487T>C family. A genotype-phenotype correlation study of a Belgian five-generation family with 12 affected family members segregating m.14487T>C was carried out. Clinical and mutation load data were available for nine family members. Biochemical analysis of the respiratory chain was performed in three muscle biopsies. Heteroplasmic m.14487T>C levels (36-52% in leucocytes, 97-99% in muscle) were found in patients with progressive myoclonic epilepsy (PME) and dystonia or progressive hypokinetic-rigid syndrome. Patients with infantile LS were homoplasmic (99-100% in leucocytes, 100% in muscle). We found lower mutation loads (between 8 and 35% in blood) in adult patients with clinical features including migraine with aura, Leber hereditary optic neuropathy, sensorineural hearing loss and diabetes mellitus type 2. Despite homoplasmic mutation loads, complex I catalytic activity was only moderately decreased in muscle tissue. m.14487T>C resulted in a broad spectrum of phenotypes in our family. Depending on the mutation load, it caused severe encephalopathies ranging from infantile LS to adult-onset PME with dystonia. This is the first report of PME as an important neurological manifestation of an isolated mitochondrial complex I defect.
    Journal of neurology, neurosurgery, and psychiatry 01/2010; 81(1):90-3. · 4.87 Impact Factor
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    Article: Opsoclonus-myoclonus syndrome: a clinicopathological confrontation.
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    ABSTRACT: Opsoclonus-myoclonus syndrome (OMS), a movement disorder characterised by chaotic eye movements and myoclonus, is a rare clinical entity. We present two cases of opsoclonus-myoclonus syndrome of paraneoplastic origin. In the first patient the syndrome was associated with a breast carcinoma and in the second patient with a non small cell lung carcinoma. However none of the commonly associated antibodies were found in these cases. From the neuropathological findings from the first patient we find arguments that support the current hypothesis on the pathophysiology of OMS namely a dysfunction in brainstem and cerebellum. We conclude that in adults with OMS one has to be very suspicious of a possible neoplastic origin of the syndrome. The antibodies associated with some cases of OMS are thought to play a role in the pathophysiology of the syndrome although the exact immunologic mechanism remains unknown. Research into the neuropathological substrate of OMS yields a broad range of abnormalities in brain stem and cerebellum. However none of these findings seem to be pathognomonic. As for the possible therapy of OMS, several immunomodulating strategies can be used with varying success. At present there is no established standard therapy.
    Acta neurologica Belgica 10/2006; 106(3):142-6. · 0.54 Impact Factor
  • Article: Central neurocytoma presenting with intraventricular hemorrhage: case report and review of literature.
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    ABSTRACT: We report a case of a 25 year old man presenting with acute headache, vomiting and nuchal rigidity. Computed Tomography (CT) scan and MRI without contrast showed a right ventricular hemorrhage surrounding a mass lesion. The tumor and hematoma were completely removed by neurosurgical transcortical-transventricular approach. Anatomopathological analysis revealed a central neurocytoma. Central neurocytoma seldom present with hemorrhage. We review 16 cases of neurocytoma with hemorrhage. It is important to recognize central neurocytoma as a cause of intraventricular hemorrhage, especially in adolescents and young adults. Outcome is often favorable when the tumor is completely removed. In some patients the clinical course is more aggressive and additional treatment such as radiotherapy, radiosurgery or chemotherapy is needed.
    Acta neurologica Belgica 01/2006; 105(4):218-25. · 0.54 Impact Factor