title: [Clinical and laboratory studies on four Chinese patients with succinate-CoA ligase deficiency noticed by mild methylmalonic aciduria].
abstract: OBJECTIVE
  To study the clinical and genetic features of the patients with secondary methylmalonic aciduria due to succinate-CoA ligase deficiency.
  
  
  METHODS
  From February 2011 to April 2014, 4 Chinese patients with succinate-CoA ligase deficiency and mild methylmalonic aciduria were enrolled in this study. The clinical course, biochemical features, brain MRI findings, and mutations were analyzed.
  
  
  RESULTS
  Four patients presented with severe psychomotor retardation, hypotonia, seizures, feeding problems and failure to thrive from the age of one day to 6 months. Three of them had intractable epilepsies. One had hearing defect. Mild methylmalonic aciduria was detected by elevated urine methylmalonic acid and blood propionylcarnitine at the age of 6 months to 2 years and 8 months. Five mutations, c. 550G>A, c. 751C>T, c. 809A>C, c. 961C>G and c. 826-2A>G in SUCLG1 of three patients were identified. On SUCLA2, one novel mutation, c. 970C>T, was found in one patient. After treatment, the disease in all four patients was improved.
  
  
  CONCLUSIONS
  Four Chinese patients with succinyl-CoA ligase deficiency caused by SUCLG1 and SUCLA2 mutations were noticed by mild methylmalonic aciduria and diagnosed using high-throughput genomic sequencing. Succinate-CoA ligase deficiency is a rare cause of methylmalonic aciduria. Biochemical and gene studies are necessary for the differential diagnoses.
authors.affiliation: Department of Pediatrics, Peking University First Hospital, Beijing 100034, China.
authors.forename: Y P
authors.initials: YP
authors.lastname: Liu
authors.forename: X Y
authors.initials: XY
authors.lastname: Li
authors.forename: Y
authors.initials: Y
authors.lastname: Ding
authors.forename: Q
authors.initials: Q
authors.lastname: Wang
authors.forename: J Q
authors.initials: JQ
authors.lastname: Song
authors.forename: Y
authors.initials: Y
authors.lastname: Zhang
authors.forename: D X
authors.initials: DX
authors.lastname: Li
authors.forename: Y P
authors.initials: YP
authors.lastname: Qin
authors.forename: Y L
authors.initials: YL
authors.lastname: Yang
mesh_terms: D000592:Amino Acid Metabolism, Inborn Errors / Q000150:complications / Q000175:diagnosis* / Q000235:genetics; D044466:Asian People; D002331:Carnitine / Q000031:analogs & derivatives / Q000097:blood; D004252:DNA Mutational Analysis; D003937:Diagnosis, Differential; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008279:Magnetic Resonance Imaging; D008764:Methylmalonic Acid / Q000652:urine; D028361:Mitochondrial Diseases / Q000150:complications / Q000175:diagnosis* / Q000235:genetics; D009154:Mutation; D013389:Succinate-CoA Ligases / Q000235:genetics
chemical_list: C003223:propionylcarnitine; D008764:Methylmalonic Acid; C000611245:SUCLG1 protein, human; D013389:Succinate-CoA Ligases; C518788:SUCLA2 protein, human; D002331:Carnitine