EC Paediatrics

Defects in conserved oligomeric Golgi (COG) complex subunits result in Congenital disorders of glycosylation (CDG) type II. These CDG subtypes has multisystem involvement. In this report, we present a 21-month-old female with Conserved Oligomeric Golgi complex subunit 6 - congenital disorders of glycosylation (COG6-CDG) who survived a complicated infantile course. She presented after birth with diarrhea, feeding intolerance, failure to thrive, hepatic failure, and recurrent febrile illnesses associated with neutropenia. A homozygous pathogenic variant in COG6 (c. 1167-24A>G) was detected by next-generation sequencing. In comparison to previous reports with the same deep intronic variant, who manifested a mild form of COG6-CDG or Shaheen syndrome, her initial presentation was severe. Follow-up after a year of recovery from a complex disease course showed significant improvement in her hepatic function and her growth and development. In addition, our patient did not manifest the typical ectodermal features of COG6-CDG.

 Keywords: Conserved Oligomeric Golgi 6 (COG); Congenital Disorder of Glycosylation (CDG); Ectodermal Dysplasia

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