title: [Clinical and genetic analysis for two children with congenital disturbance of glycosylation with PMM2 gene mutations].
abstract: OBJECTIVE
  To analyze the clinical and PMM2 gene mutation features of congenital disturbance of glycosylation caused by PMM2 gene mutation (PMM2-CDG, previously known as CDG 1a).
  
  
  METHODS
  The clinical data of two Chinese patients who were clinically diagnosed as PMM2-CDG at neurology department of Beijing Children's Hospital in 2012 were retrospectively collected. The gene mutations were identified by Sanger sequencing.
  
  
  RESULTS
  Both patients were female, aged 1 year and 1 month and 8 months respectively. The main clinical features of the two cases were developmental delay after birth, chronic diarrhea and metabolic acidosis, associated with elevated serum transaminases, and decreased antithrombin III activity. Physical examination showed esotropia, inverted nipples, and abnormal subcutaneous fat pads. The cranial MRI showed cerebellar atrophy. Both cases were treated with occupational therapy, physical therapy and speech therapy. The development was gradually improved but also delayed as compared with normal peers during follow-up for more than 3 years. Genetic analysis showed that patient 1 was compound heterozygous for c. 422G>A(p.Arg141His), which was reported for known pathogenic mutation, and c. 669C>A(p.Asp223Glu), was a new mutation. The patient 2 showed compound heterozygous mutation for c. 634A>G (p.Met212Val)and c. 713G>C(p.Arg238Pro), which were both new mutations.
  
  
  CONCLUSIONS
  PMM2-CDG is a rare metabolic disease, and the diagnosis should be considered in a child with developmental delay, elevated serum transaminases, decreased antithrombin III activity, inverted nipples, abnormal subcutaneous fat pads, esotropia, and cerebellar atrophy on MRI. It can be confirmed by PMM2 gene analysis.
authors.affiliation: Department of Neurology, Beijing Children's Hospital Affiliated to Capital Medical University, Beijing 100045, China.
authors.forename: Changhong
authors.initials: C
authors.lastname: Ren
authors.affiliation: Email: ff139@sohu.com.
authors.forename: Fang
authors.initials: F
authors.lastname: Fang
authors.forename: Yu
authors.initials: Y
authors.lastname: Huang
authors.forename: Hua
authors.initials: H
authors.lastname: Cheng
authors.forename: Lifang
authors.initials: L
authors.lastname: Dai
mesh_terms: D044466:Asian People; D018981:Congenital Disorders of Glycosylation / Q000235:genetics*; D004252:DNA Mutational Analysis; D002658:Developmental Disabilities; D005260:Female; D005820:Genetic Testing; D006031:Glycosylation; D006579:Heterozygote; D006801:Humans; D007223:Infant; D008279:Magnetic Resonance Imaging; D009154:Mutation; D017875:Phosphotransferases (Phosphomutases) / Q000235:genetics*; D012189:Retrospective Studies
chemical_list: D017875:Phosphotransferases (Phosphomutases); C519582:phosphomannomutase 2, human