Screening Using Serum Percentage of Carbohydrate-Deficient Transferrin for Congenital Disorders of Glycosylation in Children with Suspected Metabolic Disease

glycosylation (CDG) are based on clinical suspicion and analysis of transferrin (Tf) isoforms. Here we present our experience of CDG screening in children with a suspected metabolic disease by determination of serum percentage of carbohydrate-deficient transferrin (%CDT) in tandem with isoelectric focusing (IEF) analy-sis of Tf and 1-antitrypsin (1-AT). METHODS: We performed approximately 8000 serum %CDT determinations using %CDT turbidimetric im-munoassay (TIA). In selected samples, IEF analysis of Tf and 1-AT was carried out on an agarose gel (pH 4 – 8) using an electrophoresis unit. The isoforms were detected by Western blotting and visualized by color development. We performed neuraminidase digestion of serum to detect polymorphic variants of Tf