title: Atypical presentation of late-onset Tay-Sachs disease.
abstract: BACKGROUND
  Late-onset Tay-Sachs disease (LOTS) is a lysosomal storage disease caused by deficient Beta-hexosaminidase A activity.
  
  
  METHODS
  We describe a 53-year-old woman who presented with adult-onset leg weakness, and whose initial diagnosis was progressive muscular atrophy without identifiable etiology. Development of cerebellar ataxia in mid-life prompted reassessment.
  
  
  RESULTS
  Beta-hexosaminidase A quantification assay demonstrated absence of the isozyme. Genetic testing identified compound heterozygous mutations in the HEXA gene, confirming the diagnosis of LOTS.
  
  
  CONCLUSIONS
  The phenotypic spectrum of LOTS includes motor neuronopathy, ataxia, choreoathetosis, neuropathy, and psychiatric symptoms in various combinations. This patient highlights the emergence of different clinical features over many years and emphasizes the need to consider LOTS in the differential diagnosis of progressive muscular atrophy.
authors: Department of Neurology, Beth Israel Medical Center, New York, New York, USA; University of Pennsylvania, Parkinson Disease and Movement Disorders Center, 330 S. 9th Street, 2nd Floor, Suite 219, Philadelphia, Pennsylvania, 19107, USA.
authors: Andres
authors: A
authors: Deik
authors: Rachel
authors: R
authors: Saunders-Pullman
mesh_terms: D003937:Diagnosis, Differential; D004568:Electrodiagnosis; D005260:Female; D006579:Heterozygote; D006801:Humans; D008875:Middle Aged; D009134:Muscular Atrophy, Spinal / Q000175:diagnosis*; D010641:Phenotype; D013661:Tay-Sachs Disease / Q000175:diagnosis* / Q000235:genetics; D054820:beta-Hexosaminidase alpha Chain / Q000097:blood / Q000235:genetics
chemical_list: C518253:HEXA protein, human; D054820:beta-Hexosaminidase alpha Chain
keywords: ataxia; cerebellum; hexosaminidase; late-onset Tay-Sachs disease; progressive muscular atrophy