Resistant Epilepsy and Developmental Delay in a Syndromic Infant: A Case of Congenital Disorder of Glycosylation Type Ik From India.

Type I congenital disorder of glycosylation (CDG) is a group of genetic disorders that affect the biosynthesis of dolichol-linked oligosaccharides or the transfer of oligosaccharides onto nascent glycoproteins. Mutations in the ALG1 gene cause CDG type Ik. We report a ten-month-old female with CDG type Ik presenting with recurrent seizures, global developmental delay, hypotonia, and dysmorphic features. Whole-exome sequencing revealed a homozygous likely pathogenic variant chr16:5071980G>T or c.131G>T or p.Gly44Val in the ALG1 gene. Transferrin isoform analysis showed a CDG type I pattern, consistent with a glycosylation disorder. This case emphasizes the importance of early clinical suspicion, metabolic screening, and genetic testing in infants with unexplained recurrent seizures, syndromic features, and multisystemic involvement.