title: Early cardiac involvement in an infantile Sandhoff disease case with novel mutations.
abstract: BACKGROUND
  Hepatosplenomegaly is often present in infantile Sanshoff disease. However, cardiac involvement is extremely uncommon.
  
  
  METHODS
  We describe a 14-month-old female baby who exhibited mitral regurgitation and cardiomegaly at the age of 2months, dilation of the left atrium and left ventricle at age of 6months, followed by regression of developmental milestones after an episode of minor infection at age of 14months. Brain magnetic resonance imaging revealed signal changes over the bilateral thalami, bilateral cerebral white matter and left putamen. An examination of the fundus showed presence of cherry-red spots in both macular areas. The lysosomal enzymatic activities showed a marked reduction of β-hexosaminidase B (HEXB) activity. Two novel mutations of HEXB gene were identified. One of the mutations was a c.1538 T>C mutation, which predicted a p.L513P amino acid substitution of leucine to proline; the other was a c.299+5 G>A mutation, which was a splice site mutation.
  
  
  CONCLUSIONS
  Cardiac involvement might occur prior to neurological symptoms in infantile Sandhoff disease, and it should be included in the differential diagnoses of metabolic cardiomyopathies in the infantile stage.
authors.affiliation: Department of Pediatrics, Taichung Veterans General Hospital, Taichung, Taiwan; School of Medicine, Chung Shan Medical University, Taichung, Taiwan. Electronic address: leehf@hotmail.com.tw.
authors.forename: Hsiu-Fen
authors.initials: HF
authors.lastname: Lee
authors.affiliation: Department of Pediatrics, Tungs' Taichung Metroharbor Hospital, Taichung, Taiwan; School of Medicine, Chung Shan Medical University, Taichung, Taiwan. Electronic address: chi-cs@hotmail.com.
authors.forename: Ching-Shiang
authors.initials: CS
authors.lastname: Chi
authors.affiliation: Department of Pediatrics, Taichung Veterans General Hospital, Taichung, Taiwan; Institute of Molecular Biology, National Chung Hsing University, Taichung, Taiwan. Electronic address: n20248@vghtc.gov.tw.
authors.forename: Chi-Ren
authors.initials: CR
authors.lastname: Tsai
mesh_terms: D001921:Brain / Q000000981:diagnostic imaging; D009202:Cardiomyopathies / Q000000981:diagnostic imaging / Q000235:genetics* / Q000503:physiopathology*; D004252:DNA Mutational Analysis; D003937:Diagnosis, Differential; D004452:Echocardiography; D005260:Female; D054819:Hexosaminidase B / Q000235:genetics* / Q000378:metabolism; D006801:Humans; D007223:Infant; D008279:Magnetic Resonance Imaging; D009154:Mutation; D010375:Pedigree; D012497:Sandhoff Disease / Q000000981:diagnostic imaging / Q000235:genetics* / Q000503:physiopathology*
chemical_list: D054819:Hexosaminidase B
keywords: Cardiac manifestations; HEXB gene mutation; Infantile Sandhoff disease; Metabolic cardiomyopathy; Neurological features