Successful treatment of intractable epilepsy with ketogenic diet therapy in twins with ALG3-CDG

Brain Dev. 2020 Aug;42(7):539-545. doi: 10.1016/j.braindev.2020.04.008. Epub 2020 May 7.


Background: Congenital disorders of glycosylation (CDG) is a heterogeneous group of congenital metabolic diseases with multisystem clinical involvement. ALG3-CDG is a very rare subtype with only 24 cases reported so far.

Case: Here, we report two siblings with dysmorphic features, growth retardation, microcephaly, intractable epilepsy, and hemangioma in the frontal, occipital and lumbosacral regions.

Results: We studied two siblings by whole exome sequencing. A pathogenic variant in ALG3 (NM_005787.6: c.165C > T; p.Gly55=) that had been previously associated with congenital glycolysis defect type 1d was identified. Their intractable seizures were controlled by ketogenic diet.

Conclusion: Although prominent findings of growth retardation and microcephaly seen in our patients have been extensively reported before, presence of hemangioma is a novel finding that may be used as an indication for ALG3-CDG diagnosis. Our patients are the first reported cases whose intractable seizures were controlled with ketogenic diet. This report adds ketogenic diet as an option for treatment of intractable epilepsy in ALG3-CDG.

Keywords: ALG3; Congenital disorders of glycosylation; Developmental delay; Hemangioma; Intractable epilepsy; Ketogenic diet.

Publication types

  • Case Reports

MeSH terms

  • Central Nervous System Neoplasms / etiology
  • Congenital Disorders of Glycosylation / complications*
  • Congenital Disorders of Glycosylation / diagnosis*
  • Congenital Disorders of Glycosylation / genetics*
  • Craniofacial Abnormalities / etiology
  • Developmental Disabilities / etiology
  • Diet, Ketogenic*
  • Drug Resistant Epilepsy / diagnosis
  • Drug Resistant Epilepsy / diet therapy*
  • Drug Resistant Epilepsy / etiology
  • Exome Sequencing
  • Female
  • Hemangioma / etiology
  • Humans
  • Infant
  • Male
  • Mannosyltransferases / genetics*
  • Twins


  • ALG3 protein, human
  • Mannosyltransferases