title: Cryptogenic liver disease in four children: a novel congenital disorder of glycosylation.
abstract: We investigated the metabolic defect(s) of four children who presented with isolated cryptogenic chronic liver disease, coagulopathy, and abnormalities of several unrelated serum glycoproteins. Analysis of the patients' serum glycoproteins and fibroblasts suggest they have a novel congenital disorder of glycosylation (CDG). All had abnormal transferrin (Tf) isoelectric focusing (IEF) profiles. More detailed analysis of Tf by electrospray ionization mass spectrometry (ESI-MS) showed a plethora of abnormal glycosylations that included loss of 1-2 sialic acids and 1-2 galactose units, typical of Group II defects. Tf from two patients also lacked 1-2 entire oligosaccharide chains, typical of Group One disorders. Total serum N-glycans were analyzed by HPLC and matrix-assisted laser desorption/ionization mass spectrometry and also showed increased proportion of neutral glycan chains lacking sialic acids and galactose units. Analysis of patient fibroblasts eliminated CDG-Ia, through CDG-Ih, -IL and CDG-IId. Our results suggest that a subset of children with clinically asymptomatic, cryptogenic hypertransaminasemia and/or liver steato-fibrosis may represent a novel type of CDG-X with an unknown defect(s). Clinicians are encouraged to test such patients for abnormal Tf glycosylation by ESI-MS.
authors.affiliation: Department of Pediatrics, University of Naples Federico II, Italy.
authors.forename: Claudia
authors.initials: C
authors.lastname: Mandato
authors.forename: Lena
authors.initials: L
authors.lastname: Brive
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Miura
authors.forename: Joseph Alex
authors.initials: JA
authors.lastname: Davis
authors.forename: Nicolina
authors.initials: N
authors.lastname: Di Cosmo
authors.forename: Stefania
authors.initials: S
authors.lastname: Lucariello
authors.forename: Severo
authors.initials: S
authors.lastname: Pagliardini
authors.forename: Neung-Seon
authors.initials: NS
authors.lastname: Seo
authors.forename: Giancarlo
authors.initials: G
authors.lastname: Parenti
authors.forename: Raffaella
authors.initials: R
authors.lastname: Vecchione
authors.forename: Hudson H
authors.initials: HH
authors.lastname: Freeze
authors.forename: Pietro
authors.initials: P
authors.lastname: Vajro
mesh_terms: D002675:Child, Preschool; D005260:Female; D006031:Glycosylation; D006801:Humans; D007223:Infant; D008107:Liver Diseases / Q000151:congenital* / Q000175:diagnosis / Q000378:metabolism; D008297:Male; D011134:Polysaccharides / Q000097:blood; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D014168:Transferrin / Q000378:metabolism
chemical_list: D011134:Polysaccharides; D014168:Transferrin